zooplankton – NOAA Teacher at Sea Blog

September 25, 2019

Cara Nelson: Little Creatures that Rule the World, September 23, 2019

NOAA Teacher at Sea

Cara Nelson

Aboard USFWS R/V Tiglax

September 11-25, 2019

Mission: Northern Gulf of Alaska Long-Term Ecological Research project

Geographic Area of Cruise: Northern Gulf of Alaska – currently sheltering in Kodiak harbor again

Date: September 23, 2019

Weather Data from the Bridge:

Time: 13:30
Latitude: 57º47.214’ N
Longitude: 152º24.150’ E
Wind: Northwest 8 knots
Air Temperature: 11ºC (51ºF)
Air Pressure: 993 millibars
Overcast, light rain

Science and Technology Log

As we near the end of our trip, I want to focus on a topic that it is the heart of the LTER study: zooplankton. Zooplankton are probably the most underappreciated part of the ocean, always taking second stage to the conspicuous vertebrates that capture people’s attention. I would argue however, that these animals deserve our highest recognition. These small ocean drifters many of which take part in the world’s largest animal migration each day. This migration is a vertical migration from the ocean depths, where they spend their days in the darkness avoiding predators, to the surface at night, where they feed on phytoplankton (plant plankton). Among the zooplankton, the humble copepod, the “oar-footed,” “insect of the sea,” makes up 80% of the animal mass in the water column. These copepods act as a conduit of energy in the food chain, from primary producers all the way up to the seabirds and marine mammals.

Aboard the R/V Tiglax, zooplankton and copepods are collected in a variety of manners. During the day, a CalVet plankton net is used to collect plankton in the top 100 meters of the water column.

On the night shift, we alternated between a Bongo net and a Multinet depending on our sampling location. The Bongo net is lowered to 200 meters of depth (or 5 meters above the bottom depending on depth) and is towed back to the surface at a constant rate. This allows us to capture the vertical migrators during the night. How do we know where it is in the water column and its flow rate you may ask? Each net is attached to the winch via a smart cable. This cable communicates with the onboard computer and allows the scientists to monitor the tow in real time from the lab.

The Multinet is a much higher tech piece of equipment. It contains five different nets each with a cod end. It too is dropped to the same depth as the Bongo, however each net is fired open and closed from the computer at specific depths to allow for a snapshot of the community at different vertical depths.

Copepod research is the focus of the two chief scientists, Russ Hopcroft and Jennifer Questel aboard R/V Tiglax. Much of the research must occur back in the laboratories of the University of Alaska Fairbanks. For example, Jenn’s research focuses on analyzing the biodiversity of copepods in the NGA at the molecular level, using DNA barcoding to identify species and assess population genetics. A DNA barcode is analogous to a barcode you would find on merchandise like a box of cereal. The DNA barcode can be read and this gives a species level identification of the zooplankton. This methodology provides a better resolution of the diversity of planktonic communities because there are many cryptic species (morphologically identical) and early life stages that lack characteristics for positive identification. Her samples collected onboard are carefully stored in ethanol and frozen for transport back to her lab. Her winter will involve countless hours of DNA extraction, sequencing and analysis of the data.

One aspect of the LTER study that Russ is exploring is how successful certain copepod species are at finding and storing food. Neocalanus copepods, a dominate species in our collections, are arthropods that have a life cycle similar to insects. They have two major life forms, they start as a nauplius, or larval stage, and then metamorphisize into the copepodite form, in which they take on the more familiar arthropod appearance as they transition to adulthood. Neocalanus then spends the spring and summer in the NGA feasting on the rich phytoplankton blooms. They accumulate fat stores, similar to our Alaska grizzlies. In June, these lipid-rich animals will settle down into the deep dark depths of the ocean, presumably where there is less turbulence and predation. The males die shortly after mating, but the females will overwinter in a state called diapause, similar to hibernation. The females do not feed during this period of diapause and thus must have stock-piled enough lipids to not only survive the next six months, but also for the critical next step of egg production. Egg production begins in December to January and after egg release, these females – like salmon – will die as the cycle begins again.

Part of Russ’s assessment of the Neocalanus is to photograph them in the lab aboard the ship as they are collected. The size of the lipid sac is measured relative to their body size and recorded. If females do not store enough lipids, then the population could be dramatically altered the following season. These organisms that are live sorted on the ship will then be further studied back in the laboratory using another type of molecular analysis to look at their gene expression to understand if they are food-stressed as they come out of diapause.

Russ Hopcroft at microscope — *I watch in awe as Russ is able to manipulate and photograph copepods under a microscope amid the rocking ship.*

Back in the UAF laboratory, countless hours must be spent on a microscope by technicians and students analyzing the samples collected onboard. To give an idea of the scope of this work, it takes approximately 4 hours to process one sample. A typical cruise generates 250 samples for morphological analysis to community description, which includes abundance, biomass, life stage, gender, size and body weight information. There are three cruises in a season, and thus the work extends well into the spring. To save time, computers are also used to analyze a subset of the samples which are then checked by a technician. However, at this stage, the computer output does not yet meet the accuracy of a human technician. All of these approaches serve to better understand the health of the zooplankton community in the NGA. Knowing how much zooplankton there is, who is there and how fatty they are, will tell us both the quantity and quality of food available to the fish, seabirds and marine mammals that prey upon them. Significant changes both inter-annually and long-term of zooplankton community composition and abundance could have transformative effects through the food chain. This research provides critical baseline data as stressors, such as a changing climate, continue to impact the NGA ecosystem.

Personal Log

After sheltering in Kodiak harbor overnight Friday, we once again were able to head back out during a break in the weather. We departed Kodiak in blue skies and brisk winds on Saturday.

sunset — *Sunset over Marmot Island at the start of the Kodiak line on what would end up being our last night of sampling.*

We made it to the start of the Kodiak line by sundown and began our night of sampling with the goal of getting through six stations. The swells left over from the last gale were quite challenging, with safety a top priority this evening. Waves were crashing over the top rale as we worked and the boat pitched side to side. Walking the corridor from the stern to the bow required precise timing, lest you get soaked by a breaking wave, as poor Heidi did at least three times.

Despite having to pull the Methot early on one station and skip it all together on another due to the rough seas, we had an amazingly efficient and successful evening. Our team was amazing to work with and Dan captured one last photo of us as we wrapped up our shift at 6am.

night shift group photo — *The night shift “A Team”: Emily, Jenn, Jen, Cara and Heidi.*

The day crew worked fast and furious on the return to station one as once again, another gale was forecast. This gale was the worst yet, dipping down to 956 millibars in pressure with the word STORM written across the forecast screen for the entire Gulf of Alaska. Luckily we were able to make it back into Kodiak harbor by Sunday evening just as winds and waves began to build. After riding out the storm overnight we are still waiting for the 4pm forecast to reassess our final days two days. The crew grows weary of sitting idle as the precious window for sampling closes. Stay tuned for a follow up blog as I return to solid ground on Wednesday!

Did You Know?

Copepods are the most biologically diverse zooplankton and even outnumber the biodiversity of terrestrial insects!

July 5, 2019

Catherine Fuller: Out of the Sea and into the Lab, July 3, 2019

NOAA Teacher at Sea

Catherine Fuller

Aboard R/V Sikuliaq

June 29 – July 18, 2019

Mission: Northern Gulf of Alaska (NGA) Long-Term Ecological Research (LTER)

Geographic Area of Cruise: Northern Gulf of Alaska

Date: July 3, 2019

Weather Data from the Bridge

Latitude: 58° 54.647’ N
Longitude: 146° 00.022’ W
Wave Height: 4-5 ft.
Wind Speed: 1.9 knots
Wind Direction: roughly 90 degrees, but variable
Visibility: 1 nm
Air Temperature: 13.2 °C
Barometric Pressure: 1014.4 mb
Sky: Clear, then foggy

Weather overview

We have been fortunate so far to have very calm conditions. Winds have been variable or light and are expected to continue to be so through the weekend at least. Wave heights have generally been about 3 feet, although they’re up to 4-5 feet today, and are expected to drop tomorrow. The calm weather is critical for some of the testing being done, and thus is allowing more to happen.

Science and Technology Log

The focus of all of testing on board is plankton. As the base of the food web, all species depend on their health and abundance for survival. There are multiple teams who are focused on various aspects of plankton and their reaction to environmental conditions. Kira Monell is a graduate student at the University of Hawaii at Manoa who is working under the direction of Dr. Russ Hopcroft while on board. She is studying zooplankton, or the animal version of plankton. She is specifically focusing on Neocalanus flemingeri, a type of sub-arctic copepod. It is important to study zooplankton because they provide a link between phytoplankton (the plant version of plankton) and larger fish on the food web. Copepods are extremely abundant and varietal, found just about everywhere in the world. They are an important food source for most aquatic species (they exist in both salt and fresh water). They are a trophic link – a connection in the food web. Her target species is special because they mostly eat phytoplankton during the seasonal plankton blooms. They convert their food into a lot of lipids (fats) and thus are great sources of food and energy for larger fish. After fattening up, they go deep into the ocean to hibernate around mid-summer.

Kira is specifically focused on the termination of their hibernation (technically called diapause). She is doing genetic testing to see which genes are activated or deactivated during this phase of their lives. Messenger ribonucleic acid (or mRNA) coded by these genes is required to construct the enzymes that cause changes in body functions, so she is looking at levels of different mRNA in the copepods. She is expecting to see an increase in genes relating to oogenesis (egg formation). Her female copepods go into diapause ready to start making eggs, so she expects to see changes in genes relating to egg growth as they come wake up from diapause.

Kira is examining copepods through three different experiments. With some samples, she adds a stain called EDU (a dye that labels cells that are just about to divide) into her samples and then checks them at 24 hours to see which cells have divided. Because the copepods are still alive, she can check back to see what further cell division have happened over longer periods of time. A fluorescent microscope is required to see the EDU. Scientists still struggle to understand what actually triggers emergence from diapause since deep water copepods don’t experience seasonal light changes, or other potential triggers that might exist on the surface.

Another thing she is looking at is in-situ hybridization. She makes a tag that is very specific for the gene she wants to examine. When the probe gene is introduced, it attaches to the gene she wants to look at only if it is being actively copied. Kira then attaches a colored or fluorescent dye to the probe and in that way she can track which genes are being expressed in specific areas of the body.

The third project that she is working on is trancriptum analysis, which requires building a complete “catalog” that shows all the RNA used by a species. She can then look at which gene transcripts are present, and in how abundant they are, so as to compare them to the “average” version of a transcriptum to see which genes are being turned off and on under certain conditions.

To obtain samples of copepods, the zooplankton team, including Kira, uses Calvet nets. These are four long nets that terminate in collection tubes. Weight is added to the bottom of the nets and they are submerged off the stern to 100 meters of depth and then pulled back up (a process that takes roughly five minutes). The nets are then rinsed to collect the samples in the tubes, which are transferred into jars and brought to the lab for more detailed sorting and examination.

Calvet rising — The Calvet is returning to the surface after being submerged

Kira and Kate rinse net — Kira and Kate rinse the length of the nets to collect their samples in the tubes in the end.

As the Calvet rises you can see the full net. (This video has no dialogue.)

Personal Log

back deck — This is the main working deck at the stern of the ship.

Getting prepared to go out on deck safely!

Boots
Hard hat
Life vest
Cat on Deck

All of the sample collection happens on the working deck at the stern of the R/V Sikuliaq or in the adjacent Baltic Room. The back deck is equipped with a variety of cranes and winches that are designed to handle heavy weights and lines under tension. As such, it is critical to wear the proper protective gear when you’re out there: boots (preferably steel-toed), a hard hat and a flotation vest of coat. If there’s a potential to get wet or dirty, rain gear or waterproof bibs are essential to stay dry and relatively clean. Being properly dressed is a process that took getting used to, but now it’s habit. Again, we’re lucky to have had good weather, so the deck is usually warm enough to wear a t-shirt and jeans. I find it calming to be outside, so I am enjoying learning about the sampling methods of other teams by watching and sometimes assisting them. There are also observation decks at the bow that do not require safety gear. A few of us have discovered that the forward decks are much quieter and are good spaces to decompress and look for sea life.

Animals Seen in the Last 24 Hours:

We’ve seen a few species of birds including black turnstones, glaucous-winged gulls, Black-winged kittiwakes, as well as deeper water birds such as storm petrels and shearwaters. In addition, there have been small pods of dolphins in the distance and one humpback whale (all we saw was the tail).

May 15, 2019May 15, 2019

Katie Gavenus, Bonus Blog: MIXOTROPHS, May 5, 2019

NOAA Teacher at Sea

Katie Gavenus

Aboard R/V Tiglax

April 26 – May 9, 2019

Mission: Northern Gulf of Alaska Long-Term Ecological Research project

Geographic Area of Cruise: Northern Gulf of Alaska – currently in transit from ‘Seward Line’ to ‘Kodiak Line’

Date: May 5, 2019

Weather Data from the Bridge

Time: 2305
Latitude: 57^o34.6915’
Longitude: 150^o 06.9789’
Wind: 18 knots, South
Seas: 4-6 feet
Air Temperature: 46^oF (8^oC)
Air pressure: 1004 millibars
Cloudy, light rain

Science and Technology Log

I was going to just fold the information about mixotrophs into the phytoplankton blog, but this is so interesting it deserves its own separate blog!

On land, there are plants that photosynthesize to make their own food. These are called autotrophs – self-feeding. And there are animals that feed on other organisms for food – these are called heterotrophs – other-feeding. In the ocean, the same is generally assumed. Phytoplankton, algae, and sea grasses are considered autotrophs because they photosynthesize. Zooplankton, fish, birds, marine mammals, and benthic invertebrates are considered heterotrophs because they feed on photosynthetic organisms or other heterotrophs. They cannot make their own food. But it turns out that the line between phytoplankton and zooplankton is blurry and porous. It is in this nebulous area that mixotrophs take the stage!

Mixotrophs are organisms that can both photosynthesize and feed on other organisms. There are two main strategies that lead to mixotrophy. Some organisms, such as species of dinoflagellate called Ceratium, are inherently photosynthetic. They have their own chloroplasts and use them to make sugars. But, when conditions make photosynthesis less favorable or feeding more advantageous, these Ceratium will prey on ciliates and/or bacteria. Bacteria are phosphorous, nitrogen, and iron rich so it is beneficial for Ceratium to feed on them at least occasionally. Microscopy work makes it possible to see the vacuole filled with food inside the photosynthetic Ceratium.

illustration of mixotrophic dinoflagellate Ceratium — I created this drawing after viewing a number of microscopy photos of the mixotrophic dinoflagellate Ceratium under different lights and stains. This artistic rendition combines those different views to show the outside structure of the dinoflagellate as well as the nucleus, food vacuole and chloroplasts. (Drawing by Katie Gavenus)

Other organisms, including many ciliates, were long known to be heterotrophic. They feed on other organisms, and it is particularly common for them to eat phytoplankton and especially cryptophyte algae. Recent research has revealed, however, that many ciliates will retain rather than digest the chloroplasts from the phytoplankton they’ve eaten and use them to photosynthesize for their own benefit. Viewing these mixotrophs under blue light with a microscope causes the retained chloroplasts to fluoresce. I saw photos of them and they are just packed with chloroplasts!

illustration of mixotrophic ciliate Tontonia sp. — The mixotrophic ciliate Tontonia sp. eats phytoplankton but retains the chloroplasts from their food in order to photosynthesize on their own! I made this drawing based off of photos, showing both the outside structure of the Tontonia and how the chloroplasts fluoresce as red when viewed with blue light. (Drawing by Katie Gavenus)

Mixotrophs are an important part of the Gulf of Alaska ecosystem. They may even help to explain how a modestly productive ecosystem (in terms of phytoplankton) can support highly productive upper trophic levels. Mixotrophy can increase the efficiency of energy transfer through the trophic levels, so more of the energy from primary productivity supports the growth and reproduction of upper trophic levels. They also may increase the resiliency of the ecosystem, since these organisms can adjust to variability in light, nutrients, and phytoplankton availability by focusing more on photosynthesis or more on finding prey. Yet little is known about mixotrophs. Only about one quarter of the important mixotroph species in the Gulf of Alaska have been studied in any way, shape or form!

Researchers are trying to determine what kinds of phytoplankton the mixotrophic ciliates and dinoflagellates are retaining chloroplasts from. They are also curious whether this varies by location, season or year. Understanding the conditions in which mixotrophic organisms derive energy from photosynthesis and the conditions in which they choose to feed is another area of research focus, especially because it has important ramifications for carbon and nutrient cycling and productivity across trophic levels. And it is all very fascinating!

food web illustration — A drawing illustrating a fascinating, tightly linked portion of the Gulf of Alaska food web. Mesodinium rubrum must eat cryptophyte algae (this is called obligate feeding). The Mesodinium rubrum retain the chloroplasts from the cryptophyte algae, using them to supplement their own diet through photosynthesis. In turn, Dinophysis sp. must feed on Mesodinium rubrum. And the Dinophysis retain the chloroplasts from the Mesodinium that originally were from cryptophyte algae! (Drawing by Katie Gavenus)

Did you know?

Well over half of the oxygen on earth comes from photosynthetic organisms in the ocean. So next time you take a breath, remember to thank phytoplankton, algae, and marine plants!

Personal Log:

Tonight was likely our last full night of work, as we expect rough seas and high winds will roll in around midnight tomorrow and persist until the afternoon before we head back to Seward. We were able to get bongo net sampling completed at 6 stations along the Kodiak Line, and hope that in the next two nights we can get 2-4 stations done before the weather closes in on us and 2-4 nets on the last evening as we head back to Seward.

Despite our push to get 6 stations finished tonight, we took time to look more closely at one of the samples we pulled up. It contained a squid as well as a really cool parasitic amphipod called Phronima that lives inside of a gelatinous type of zooplankton called doliolids. Check out the photos and videos below for a glimpse of these awesome creatures (I couldn’t figure out how to mute the audio, but I would recommend doing that for a less distracting video experience).

A parasitic Phronima amphipod. This animal typically lives inside doliolids, a type of gelatinous zooplankton. Apparently its body structure and fierce claw-like appendages inspired the design of “Predator.”

April 30, 2019May 3, 2019

Katie Gavenus: Thinking Like A Hungry Bird, April 28, 2019

NOAA Teacher at Sea

Katie Gavenus

Aboard R/V Tiglax

April 26-May 9, 2019

Mission: Northern Gulf of Alaska Long-Term Ecological Research project

Geographic Area of Cruise: Northern Gulf of Alaska – currently on the ‘Middleton [Island] Line’

Date: April 28, 2019

Weather Data from the Bridge

Time: 1715
Latitude: 59^o 39.0964’ N
Longitude: 146^o05.9254’ W
Wind: Southeast, 15 knots
Air Temperature: 10^oC (49^oF)
Air pressure: 1034 millibars
Cloudy, no precipitation

Science and Technology Log

Yesterday was my first full day at sea, and it was a special one! Because each station needs to be sampled both at night and during the day, coordinating the schedule in the most efficient way requires a lot of adjustments. We arrived on the Middleton Line early yesterday afternoon, but in order to best synchronize the sampling, the decision was made that we would wait until that night to begin sampling on the line. We anchored near Middleton Island and the crew of R/V Tiglax ferried some of us to shore on the zodiac (rubber skiff).

This R&R trip turned out to be incredibly interesting and relevant to the research taking place in the LTER. An old radio tower on the island has been slowly taken over by seabirds… and seabird scientists. The bird biologists from the Institute for Seabird Research and Conservation have made modifications to the tower so that they can easily observe, study, and band the black-legged kittiwakes and cormorants that choose to nest on the shelfboards they’ve augmented the tower with. We were allowed to climb up into the tower, where removable plexi-glass windows look out onto each individual pair’s nesting area. This early in the season, the black-legged kittiwakes are making claims on nesting areas but have not yet built nests. Notes written above each window identified the birds that nested there last season, and we were keen to discern that many of the pairs had returned to their spot.

Gavenus1Birds — Black-legged kittiwakes are visible through the observation windows in the nesting tower on Middleton Island.

Gavenus2Birds — Nesting tower on Middleton Island.

The lead researcher on the Institute for Seabird Research and Conservation (ISRC) project was curious about what the LTER researchers were finding along the Middleton Line stations. He explained that the birds “aren’t happy” this spring and are traveling unusually long distances and staying away for multiple days, which might indicate that these black-legged kittiwakes are having trouble finding high-quality, accessible food. In particular, he noted that he hasn’t seen any evidence they’ve been consuming the small lantern fish (myctophids) that generally are an important and consistent food source from them in the spring. These myctophids tend to live offshore from Middleton Island and migrate to the surface at night. We’ll be sampling some of that area tonight, and I am eager to see if we might catch any in the 0.5 mm mesh ‘bongo’ nets that we use to sample zooplankton at each station.

The kittiwakes feed on myctophids. The myctophids feed on various species of zooplankton. The zooplankton feed on phytoplankton, or sometimes microzooplankton that in turn feeds on phytoplankton. The phytoplankton productivity is driven by complex interactions of environmental conditions, impacted by factors such as light availability, water temperature and salinity as well as the presence of nutrients and trace metals. And these water conditions are driven by abiotic factors – such as currents, tides, weather, wind, and freshwater input from terrestrial ecosystems – as well as the biotic processes that drive the movement of carbon, nutrients, and metals through the ecosystem.

Scientists deploy CTD — This CTD instrument and water sampling rosette is deployed at each station during the day to collect information about temperature and salinity. It also collects water that is analyzed for dissolved oxygen, nitrates, chlorophyll, dissolved inorganic carbon, dissolved organic carbon, and particulates.

CTD at sunset — When the sun sets, the CTD gets a break, and the night crew focuses on zooplankton.

Part of the work of the LTER is to understand the way that these complex factors and processes influence primary productivity, phytoplankton, and the zooplankton community structure. In turn, inter-annual or long-term changes in phytoplankton and zooplankton community structure likely have consequences for vertebrates in and around the Gulf of Alaska, like seabirds, fish, marine mammals, and people. In other words, zooplankton community structure is one piece of understanding why the kittiwakes are or are not happy this spring. It seems that research on zooplankton communities requires, at least sometimes, to consider the perspective of a hungry bird.

Peering at a jar of copepods and euphausiids (two important types of zooplankton) we pulled up in the bongo nets last night, I was fascinated by the way they look and impressed by the amount of swimming, squirming life in the jar. My most common question about the plankton is usually some variation of “Is this …” or “What is this?” But the questions the LTER seeks to ask are a little more complex.

Considering the copepods and euphausiids, these researchers might ask, “How much zooplankton is present for food?” or “How high of quality is this food compared to what’s normal, and what does that mean for a list of potential predators?” or “How accessible and easy to find is this food compared to what’s normal, and what does that mean for a list of potential predators?” They might also ask “What oceanographic conditions are driving the presence and abundance of these particular zooplankton in this particular place at this particular time?” or “What factors are influencing the life stage and condition of these zooplankton?”

Copepods in a jar — Small copepods are among the types of zooplankton we collected with the bongo nets last night.

As we get ready for another night of sampling with the bongo nets, I am excited to look more closely at the fascinating morphology (body-shape) and movements of the unique and amazing zooplankton species. But I will also keep in mind some of the bigger picture questions of how these zooplankton communities simultaneously shape, and are shaped by, the dynamic Gulf of Alaska ecosystem. Over the course of the next 3 blogs, I plan to focus first on zooplankton, then zoom in to primary production and phytoplankton, and finally dive more into nutrients and oceanographic characteristics that drive much of the dynamics in the Gulf of Alaska.

Personal Log

Life on the night shift requires a pretty abrupt change in sleep patterns. Last night, we started sampling around 10 pm and finished close to 4 am. To get our bodies more aligned with the night schedule, the four of us working night shift tried to stay up for another hour or so. It was just starting to get light outside when I headed to my bunk. Happily, I had no problem sleeping until 2:30 this afternoon! I’m hoping that means I’m ready for a longer night tonight, since we’ll be deploying the bongo nets in deeper water as we head offshore along the Middleton Line.

While on Middleton Island, we marveled at a WWII shipwreck that has been completely overtaken by seabirds for nesting.

Shipwreck filled with plants — Inputs of seabird guano, over time, have fertilized the growth of interesting lichens, mosses, grasses, and even shrubs on the sides and top of the rusty vessel.

Did You Know?

Imagine you have a copepod that is 0.5 mm long and a copepod that is 1.0 mm long. Because the smaller copepod is half as big in length, height, and width, overall that smaller copepod at best offers only about 1/8^th as much food for a hungry animal. And that assumes that it is as calorie-dense as the larger copepod.

Question of the Day:

Are PCBs biomagnifying in top marine predators in the Gulf of Alaska? Are there resident orca populations in Alaska that are impacted in similar ways to the Southern Resident Orca Whale population [in Puget Sound] (by things like toxins, noise pollution, and decreasing salmon populations? Is it possible for Southern Resident Orca Whales to migrate and successfully live in the more remote areas of Alaska? Questions from Lake Washington Girl’s Middle School 6^th grade science class.

These are great questions! No one on board has specific knowledge of this, but they have offered to put me in contact with researchers that focus on marine mammals, and orcas specifically, in the Gulf of Alaska. I’ll keep you posted when I know more!

September 15, 2018October 4, 2018

Mark Van Arsdale: What Makes Up an Ecosystem? Part III – Zooplankton, September 15, 2018

NOAA Teacher at Sea

Mark Van Arsdale

Aboard R/V Tiglax

September 11 – 26, 2018

Mission: Long Term Ecological Monitoring

Geographic Area of Cruise: North Gulf of Alaska

Date: September 15, 2018

Weather Data from the Bridge

Mostly cloudy, winds southerly 20 knots, waves to eight feet

57.56 N, 147.56 W (in transit from Gulf of Alaska Line to Kodiak Line)

Science Log

What Makes Up an Ecosystem? Part III Zooplankton

The North Gulf of Alaska Long-term Ecological Research Project collects zooplankton in several different ways. The CalVET Net is dropped vertically over the side of the boat to a depth of 100 meters and then retrieved. This net gives researchers a vertical profile of what is going on in the water column. The net has very fine mesh in order to collect very small plankton. Some of these samples are kept alive for later experiments. Others are preserved in ethanol for later genetic analysis. One of the scientists aboard is interested in the physiological details of what makes copepods thrive or not. Copepods are so important to the food webs of the Gulf of Alaska, that their success or failure can ultimately determines the success or failure of many other species in the ecosystem. When “the blob” hit the Gulf of Alaska in 2014-2016, thousands and thousands of sea birds died. During those same years, copepods were shown to be less successful in their growth and egg production.

Chief Scientist Russ Hopcroft prepping the Multi-net

The second net used to collect zooplankton is the Multi-net. We actually use two different Multi-nets. The first is set up to do a vertical profile. In the morning, it’s dropped vertically behind the boat. Four or five times a night, we tow the second Multi-net horizontally while the boat moves slowly forward at two knots. This allows us to collect a horizontal profile of plankton at specific depths. If the water depth is beyond 200 meters, we will lower the net to that depth and open the first net. The first net samples between 200 and 100 meters, above 100 meters we open the second net. As we go up each net is opened in decreasing depth increments, the last one being very close to the surface. Once the net is retrieved, we wash organisms down into the cod end, remove the cod end, and preserve the samples in glass jars with formalin. In a busy night, we may put away twenty-five pint-sized samples of preserved zooplankton. When those samples go back to Fairbanks they have to be hand-sorted by a technician to determine the numbers and relative mass of each species. We are talking hours and hours of time spend looking through a microscope. One night of work on the Tiglax may produce one month of work for technicians in the lab.

Underwater footage of a Multi-net triggering.

The last type of net we use is a Bongo net. Its steel frame looks like the frame of large bongo drums. Hanging down behind the frame is two fine mesh nets, approximately seven feet long terminating in a hard plastic sieve or cod end. Different lines use different nets based on the specific questions researchers have for that transect line or the technique used on previous years transects. To maintain a proper time series comparison from year to year, techniques and tools have to stay consistent.

I’ve spent a little bit of time under the microscope looking at some of the zooplankton samples we have brought in. They are amazingly diverse. The North Gulf of Alaska has two groups of zooplankton that can be found in the greatest abundance: copepods and euphausiids (krill.) These are food for most other animals in the North Gulf of Alaska. Fish, seabirds, and baleen whales all eat them. Beyond these two, I was able to observe the beating cilia of ctenophores and the graceful flight of pteropods or sea angels, the ghost-like arrow worms, giant-eyed amphipods, and dozens of others.

Deep sea squid, an example of a vertical migrator caught in our plankton trawls

By far my favorite zooplankton to watch under the microscope was the larvae of the goose neck barnacle. Most sessile marine organisms spend the early, larval stage of their lives swimming amongst the throngs of migrating zooplankton. Barnacles are arthropods, which are defined by their exoskeletons and segmented appendages. Most people would recognize barnacles encrusting the rocks of their favorite coastline, but when I show my students videos of barnacles feeding most are surprised to see the delicate feeding structures and graceful movements of this most durable intertidal creature. When submerged, barnacles open their shells and scratch at particles in the water with elongated combs that are really analogous to legs. The larva of the goose neck barnacle has profusely long feeding appendages and a particularly beautiful motion as it feeds.

We have to “fish” for zooplankton at night for two reasons. The first is logistical. Some work needs to get done at night when the winch is not being used by the CTD team. The second is biological. Most of the zooplankton in this system are vertical migrators. They rise each night to feed on phytoplankton near the surface and then descend back down to depth to avoid being seen in the daylight by their predators. This vertical migration was first discovered by sonar operators in World War II. While looking for German U-boats, it was observed that the ocean floor itself seemed to “rise up” each night. After the war, better techniques were developed to sample zooplankton, and scientists realized that the largest animal migration on Earth takes place each night and each morning over the entirety of the ocean basins.

One of my favorite videos on plankton.

Personal Log

The color of water

This far offshore, the water we are traveling through is almost perfectly clear, yet the color of the ocean seems continuously in flux. Today the sky turned gray and so did the ocean. As the waves come up, the texture of the ocean thickens and the diversity of reflection and refraction increases. Look three times in three directions, and you will see three hundred different shades of grey or blue. If the sun or clouds change slightly, so does the ocean.

The sea is anything but consistent. Rips or streaks of current can periodically be seen separating the ocean into distinct bodies. So far in our trip, calm afternoons have turned into windy and choppy evenings. Still, the crew tells me that by Gulf of Alaska standards, we are having amazing weather.

Variations in water texture created by currents in the Gulf of Alaska.

Did You Know?

The bodies of puffins are much better adapted to diving than flying. A puffin with a full belly doesn’t fly to get out of the way of the boat so much as butterfly across the surface of the water. Michael Phelps has nothing on a puffin flapping its way across the surface of the water.

Animals Seen Today

Fin and sperm whales in the distance
Storm Petrels, tufted puffins, Laysan and black-footed and short-tailed albatross, flesh footed shearwaters

August 27, 2017

Amanda Dice: Bongos in the Water, August 24, 2017

NOAA Teacher at Sea

Amanda Dice

Aboard NOAA Ship Oscar Dyson

August 21 – September 2, 2017

Mission: Juvenile Pollock Fishery Survey

Geographic area of cruise: Western Gulf of Alaska

Date: August 24, 2017

Weather Data: 11.5 C, Foggy

Latitude 56 35.5 N, Longitude 153 21.9 W

This map on the bridge helps everyone keep track of where we are and where we are headed next.

Science and Technology Log

At each sampling site, we take two types of samples. First, we dip what are called bongo nets into the water off of the side of the boat. These nets are designed to collect plankton. Plankton are tiny organisms that float in the water. Then, we release long nets off of the back of the boat to take a fish sample. There is a variety of fish that get collected. However, the study targets five species, one of which is juvenile walleye pollock, Gadus chalcogrammus. These fish are one of the most commercially fished species in this area. I will go into more detail about how the fish samples are collected in a future post. For now, I am going to focus on how plankton samples are collected and why they are important to this survey.

Juvenile walleye pollock are fish that are only a few inches long. These fish can grow to much larger sizes as they mature.

As you can see in the photos below, the bongo nets get their name because the rings that hold the nets in place resemble a set of bongo drums. The width of the nets tapers from the ring opening to the other end. This shape helps funnel plankton down the nets and into the collection pieces found at the end of the nets. These collection devices are called cod ends.

Bongo nets being lowered into the water off of the side of the ship.

This is the collection end, or cod end, of the bongo nets.

This study uses two different size bongo nets. The larger ones are attached to rings that are 60 centimeters in diameter. These nets have a larger mesh size at 500 micrometers. The smaller ones are attached to rings that are 20 centimeters in diameter and have a smaller mesh size at 150 micrometers. The different size nets help us take samples of plankton of different sizes. While the bongo nets will capture some phytoplankton (plant-like plankton) they are designed to mainly capture zooplankton (animal-like plankton). Juvenile pollock eat zooplankton. In order to get a better understanding of juvenile pollock populations, it is important to also study their food sources.

Here I am, helping to bring the bongo nets back on to the ship.

Once the bongo nets have been brought back on board, there are two different techniques used to assess which species of zooplankton are present. The plankton in nets #1 of both the small and large bongo are placed in labeled jars with preservatives. These samples will be shipped to a lab in Poland once the boat is docked. Here, a team will work to identify all the zooplankton in each jar. We will probably make it to at least sixty sampling sites on the first leg of this survey. That’s a lot of zooplankton!

A jar of preserved zooplankton is ready to be identified.

The other method takes place right on the ship and is called rapid zooplankton assessment (RZA). In this method, a scientist will take a small sample of what was collected in nets #2 of both the small and large bongos. The samples are viewed under a microscope and the scientist keeps a tally of which species are present. This number gives the scientific team some immediate feedback and helps them get a general idea about which species of zooplankton are present. Many of the zooplankton collected are krill, or euphausiids, and copepods. One of the most interesting zooplankton we have sampled are naked pteropods, or sea angels. This creature has structures that look very much like a bird’s wings! We also saw bioluminescent zooplankton flash a bright blue as we process the samples. Even though phytoplankton is not a part of this study, we also noticed the many different geometric shapes of phytoplankton called diatoms.

A naked pteropod, or sea angel, as seen through the microscope.

Personal Log

Both the scientific crew and the ship crew work one of two shifts. Everyone works either midnight to noon or noon to midnight. I have been lucky enough to work from 6am – 6pm. This means I get the chance to work with everyone on board at different times of the day. It has been really interesting to learn more about the different ship crew roles necessary for a survey like this to run smoothly. One of the more fascinating roles is that of the survey crew. Survey crew members act as the main point of communication between the science team and the ship crew. They keep everyone informed about important information throughout the day as well as helping out the science team when we are working on a sample. They are responsible for radioing my favorite catchphrase to the bridge and crew, “bongos in the water.”

A sign of another great day on the Gulf of Alaska.

Did You know?

You brush your teeth with diatoms! The next time you brush your teeth, take a look at the ingredients on your tube of toothpaste. You will see “diatomaceous earth” listed. Diatomaceous earth is a substance that contains the silica from ancient diatoms. Silica gives diatoms their rigid outer casings, allowing them to have such interesting geometric shapes. This same silica also helps you scrub plaque off of your teeth!

August 23, 2017

Christine Webb: August 19, 2017

NOAA Teacher at Sea

Christine Webb

Aboard NOAA Ship Bell M. Shimada

August 11 – 26, 2017

Mission: Summer Hake Survey Leg IV

Geographic Area of Cruise: Pacific Ocean from Newport, OR to Port Angeles, WA

Date: 8/19/2017

Latitude: 48.59 N

Longitude: 126.59 W

Wind Speed: 15 knots

Barometric Pressure: 1024.05 mBars

Air Temperature: 59 F

Weather Observations: Sunny

Science and Technology Log:

You wouldn’t expect us to find tropical sea creatures up here in Canadian waters, but we are! We have a couple scientists on board who are super interested in a strange phenomenon that’s been observed lately. Pyrosomes (usually found in tropical waters) are showing up in mass quantities in the areas we are studying. No one is positive why pyrosomes are up here or how their presence might eventually affect the marine ecosystems, so scientists are researching them to figure it out. One of the scientists, Olivia Blondheim, explains a bit about this: “Pyrosomes eat phytoplankton, and we’re not sure yet how such a large bloom may impact the ecosystem overall. We’ve already seen that it’s affecting fishing communities because their catches have consisted more of pyrosomes than their target species, such as in the shrimp industry.”

IMG_20170817_100329068 — Sorting through a bin of pyrosomes

Pyrosomes are a type of tunicate, which means they’re made up of a bunch of individual organisms. The individual organisms are called zooids. These animals feed on phytoplankton, and it’s very difficult to keep them alive once they’re out of the water. We have one alive in the wet lab right now, though, so these scientists are great at their jobs.

We’ve found lots of pyrosomes in our hake trawls, and two of our scientists have been collecting a lot of data on them. The pyrosomes are pinkish in color and feel bumpy. Honestly, they feel like the consistency of my favorite candy (Sour Patch Kids). Now I won’t be able to eat Sour Patch Kids without thinking about them. Under the right conditions, a pyrosome will bioluminesce. That would be really cool to see, but the conditions have to be perfect. Hilarie (one of the scientists studying them) is trying to get that to work somehow before the trip is over, but so far we haven’t been able to see it. I’ll be sure to include it in the blog if she gets it to work!

One of the things that’s been interesting is that in some trawls we don’t find a single pyrosome, and in other trawls we see hundreds. It really all depends on where we are and what we’re picking up. A lot of research still needs to be done on these organisms and their migration patterns, and it’s exciting to be a small part of that.

Personal Log:

The science crew continues to work well together and have a lot of fun! Last night we had an ice cream sundae party after dinner, and I was very excited about the peanut butter cookie dough ice cream. My friends said I acted more excited about that than I did about seeing whales (which is probably not true. But peanut butter cookie dough ice cream?! That’s genius!). After our ice cream sundaes, we went and watched the sunset up on the flying bridge. It was gorgeous, and we even saw some porpoises jumping in the distance.

It was the end to another exciting day. My favorite part of the day was probably the marine mammal watch where we saw all sorts of things, but I felt bad because I know that our chief scientist was hoping to fish on that spot. Still, it was so exciting to see whales all around our ship, and some sea lions even came and swam right up next to us. It was even more exciting than peanut butter cookie dough ice cream, I promise. Sometimes I use this wheel to help me identify the whales:

IMG_20170818_094058774_HDR — Whale identification wheel

Now we’re gearing up for zooplankton day. We’re working in conjunction with the Nordic Pearl, a Canadian vessel, and they’ll be fishing on the transects for the next couple days. That means we’ll be dropping vertical nets and doing some zooplankton studies. I’m not exactly sure what that will entail, but I’m excited to learn about it! So far the only zooplankton I’ve seen is when I was observing my friend Tracie. She was looking at phytoplankton on some slides and warned me that sometimes zooplankton dart across the phytoplankton. Even though she warned me, it totally startled me to see this giant blob suddenly “run” by all the phytoplankton! Eeeeep! Hopefully I’ll get to learn a lot more about these creatures in the days coming up.

May 8, 2017May 11, 2017

Kimberly Scantlebury: It’s All About the Little Things, May 8, 2017

NOAA Teacher at Sea

Kimberly Scantlebury

Aboard NOAA Ship Pisces

May 1-May 12, 2017

Mission: SEAMAP Reef Fish Survey

Geographic Area of Cruise: Gulf of Mexico

Date: May 8, 2017

Weather Data from the Bridge

Time: 18:00

Latitude: 2755.757 N, Longitude: 9200.0239 W

Wind Speed: 14.21 knots, Barometric Pressure: 1015.3 hPa

Air Temperature: 24.56 C, Water Temperature: 24.4 C

Salinity: 36.37 PSU, Conditions: 50% cloud cover, light wind, seas 2-4 feet

Science and Technology Log

The CTD (conductivity, temperature, depth) array is another important tool. It goes down at each station, which means data is captured ten-twelve times a day. It drops 50 m/min so it only takes minutes to reach the bottom where other winch/device systems can take an hour to do the same. This array scans eight times per second for the following environmental factors:

Depth (m)
Conductivity (converts to salinity in ppt)
Temperature (C)
Dissolved oxygen (mg/mL)
Transmissivity (%)
Fluorescence (mg/m^3)
Descent rate (m/sec)
Sound velocity (m/sec)
Density (kg/m^3)

There are two sensors for most readings and the difference between them is shown in real time and recorded. For example, the dissolved oxygen sensor is most apt to have calibration issues. If the two sensors are off each other by 0.1 mg/L then something needs to be done.

Software programs filter the data to cut out superfluous numbers such as when the CTD is acclimating in the water for three minutes prior to diving. Another program aligns the readings when the water is working through the sensors. Since a portion of water will reach one sensor first, then another, then another, and so on, the data from each exact portion of water is aligned with each environmental factor. There are many other sophisticated software programs that clean up the data for use besides these two.

These readings are uploaded to the Navy every twelve hours, which provides almost real-time data of the Gulf. The military uses this environmental data to determine how sound will travel through sound channels by locating thermoclines as well as identifying submarines. NOAA describes a thermocline as, “the transition layer between warmer mixed water at the ocean’s surface and cooler deep water below.” Sound channels are how whales are able to communicate over long distances.

NOAA Ocean Explorer: Sound in the Sea 2001 — This “channeling” of sound occurs because of the properties of sound and the temperature and pressure differences at different depths in the ocean. (NOAA)

The transmissometer measures the optical properties of the water, which allows scientists to track particulates in the water. Many of these are clay particles suspended in the water column. Atmospheric scientists are interested in particulates in the air and measure 400 m. In the water, 0.5 m is recorded since too many particulate affects visibility very quickly. This affects the cameras since light reflecting off the clay can further reduce visibility.

Fluorescence allows scientists to measure chlorophyll A in the water. The chlorophyll molecule is what absorbs energy in photosynthetic plants, algae, and bacteria. Therefore, it is an indicator of the concentration of organisms that make up the base of food chains. In an ecosystem, it’s all about the little things! Oxygen, salinity, clay particles, photosynthetic organisms, and more (most we can not actually see), create a foundation that affects the fish we catch more than those fish affect the little things.

The relationship between abiotic (nonliving) and biotic (living) factors is fascinating. Oxygen is a great example. When nitrates and phosphates wash down the Mississippi River from the breadbasket of America, it flows into the Gulf of Mexico. These nutrients can make algae go crazy and lead to algae blooms. The algae then use up the oxygen, creating dead zones. Fish can move higher up the water column or away from the area, but organisms fixed to the substrate (of which there are many in a reef system) can not. Over time, too many algae blooms can affect the productivity of an area.

Salt domes were created millions of years ago when an ancient sea dried up prior to reflooding into what we have today. Some salt domes melted and pressurized into super saline water, which sinks and pools. These areas create unique microclimates suitable to species like some mussels. A microclimate is a small or restricted area with a climate unique to what surrounds it.

The ship’s sonar revealing a granite spire a camera array was deployed on.

Another great example is how geology affects biology. Some of these salt domes collapsed leaving granite spires 30-35 meters tall and 10 meters across. These solid substrates create a magical biological trickle down effect. The algae and coral attach to the hard rock, and soon bigger and bigger organisms populate this microclimate. Similar microclimates are created in the Gulf of Mexico from oil rigs and other hard surfaces humans add to the water.

Jillian’s net also takes a ride with the CTD. She is a PhD student at Texas A&M University studying the abundance and distribution of zooplankton in the northern Gulf of Mexico because it is the primary food source of some commercially important larval fish species. Her net is sized to capture the hundreds of different zooplankton species that may be populating the area. The term zooplankton comes from the Greek zoo (animal) and planktos (wanderer/drifter). Many are microscopic, but Jillian’s samples reveal some translucent critters you can see with the naked eye. Her work and the work of others like her ensures we will have a deeper understanding of the ocean.

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Personal Log

Prior to this I had never been to the Gulf of Mexico other than on a cruise ship (not exactly the place to learn a lot of science). It has been unexpected to see differences and parallels between the Gulf of Mexico and Gulf of Maine, which I am more familiar. NOAA scientist, John, described the Gulf to me as, “a big bathtub.” In both, the geology of the area, which was formed millions of years ago, affects that way these ecosystems run.

Quote of the Day:
Jillian: “Joey, are we fishing at this station?”
Joey: “I dunno. I haven’t had my coffee yet.”
Jillian: “It’s 3:30 in the afternoon!”

Did You Know?

Zooplankton in the Gulf of Mexico are smaller than zooplankton in the Gulf of Maine. Larger species are found in colder water.

why_zoo — Zooplankton under microscope (NOAA)

July 23, 2015August 21, 2021

Michael Wing: Introduction to El Niño, July 22, 2015

NOAA Teacher at Sea
Michael Wing
Aboard R/V Fulmar
July 17 – 25, 2015

Mission: 2015 July ACCESS Cruise
Geographical Area of Cruise: Pacific Ocean west of Bodega Bay, California
Date: July 22, 2015

Weather Data from the Bridge: Northwest wind 15-25 knots, wind waves 3’-5’, northwest swell 4’ – 6’ at eight seconds, overcast.

Science and Technology Log

UC Davis graduate student and Point Blue Conservation Science intern Kate Davis took some plankton we collected to the Bodega Marine lab in Bodega Bay. She said she is seeing “tropical” species of plankton. A fellow graduate student who is from Brazil peeked into the microscope and said the plankton looked like what she sees at home in Brazil. The flying fish we saw is also anomalous, as is the number of molas (ocean sunfish) we are seeing. Plankton can’t swim, so some of our water must have come from a warm place south or west of us.

Farallones — The Farallon Islands are warmer this year

The surface water is several degrees warmer than it normally is this time of year. NOAA maintains a weather buoy near Bodega Bay, California that shows this really dramatically. Click on this link – it shows the average temperature in blue, one standard deviation in gray (that represents a “normal” variation in temperatures) and the actual daily temperature in red.

NOAA buoy data — Surface seawater temperatures from a NOAA buoy near Bodega Bay, California

http://bml.ucdavis.edu/boon/climatology.html

As you can see, the daily temperatures were warm last winter and basically normal in the spring. Then in late June they shot up several degrees, in a few days and have stayed there throughout this month. El Niño? Climate change? The scientists I am with say it’s complicated, but at least part of what is going on is due to El Niño.

Ryan at flying bridge — San Francisco State University student and Point Blue intern Ryan Hartnett watches El Nino

So what exactly is El Niño?

My students from last year know that the trade winds normally push the surface waters of the world’s tropical oceans downwind. In the Pacific, that means towards Asia. Water wells up from the depths to take its place on the west coasts of the continents, which means that places like Peru have cold water, lots of fog, and good fishing. The fishing is good because that deep water has lots of nutrients for phytoplankton growth like nitrate and phosphate (fertilizer, basically) and when it hits the sunlight lots of plankton grow. Zooplankton eat the phytoplankton; fish eat the zooplankton, big fish eat little fish and so on.

During an El Niño event, the trade winds off the coast of Peru start to weaken and that surface water bounces back towards South America. This is called a Kelvin wave. Instead of flowing towards Asia, the surface water in the ocean sits there in the sunlight and it gets warmer. There must be some sort of feedback mechanism that keeps the trade winds weak, but the truth is that nobody really understands how El Niño gets started. We just know the signs, which are (1) trade winds in the South Pacific get weak (2) surface water temperatures in the eastern tropical pacific rise, (3) the eastern Pacific Ocean and its associated lands get wet and rainy, (4) the western Pacific and places like Australia, Indonesia, and the Indian Ocean get sunny and dry.

This happens every two to seven years, but most of the time the effect is weak. The last time we had a really strong El Niño was 1997-1998, which is when our current cohort of high school seniors was born. That year it rained 100 inches in my yard, and averaged over an inch a day in February! So, even though California is not in the tropics we feel its effects too.

Sausalito sunset — Sunset from the waterfront in Sausalito, California

We are in an El Niño event now and NOAA is currently forecasting an excellent chance of a very strong El Niño this winter.

NOAA map — Sea surface temperature anomalies Summer 2015. Expect more red this winter.

What about climate change and global warming? How is that related to El Niño? There is no consensus on that; we’ve always had El Niño events and we’ll continue to have them in a warmer world but it is possible they might be stronger or more frequent.

Personal Log

So, is El Niño a good thing? That’s not a useful question. It’s a part of our climate. It does make life hard for the seabirds and whales because that layer of warm water at the surface separates the nutrients like nitrate and phosphate, which are down deep, from the sunlight. Fewer phytoplankton grow, fewer zooplankton eat them, there’s less krill and fish for the birds and whales to eat. However, it might help us out on land. California’s drought, which has lasted for several years now, may end this winter if the 2015 El Niño is as strong as expected.

Golden Gate Bridge — Rain will come again to California

Did You Know? El Niño means “the boy” in Spanish. It refers to the Christ child; the first signs of El Niño usually become evident in Peru around Christmas, which is summer in the southern hemisphere. The Spanish in colonial times were very fond of naming things after religious holidays. You can see that in our local place names. For instance, Marin County’s Point Reyes is named after the Feast of the Three Kings, an ecclesiastical holy day that coincided with its discovery by the Spanish. There are many other examples, from Año Nuevo on the San Mateo County coast to Easter Island in Chile.

Window selfie — Michael Wing takes a selfie in his reflection in the boat’s window

July 21, 2015August 21, 2021

Michael Wing: How to Sample the Sea, July 20, 2015

NOAA Teacher at Sea
Michael Wing
Aboard R/V Fulmar
July 17 – 25, 2015

Mission: 2015 July ACCESS Cruise
Geographical Area of Cruise: Pacific Ocean west of Marin County, California
Date: July 20, 2015

Weather Data from the Bridge: 15 knot winds gusting to 20 knots, wind waves 3-5’ and a northwest swell 3-4’ four seconds apart.

Science and Technology Log

On the even-numbered “lines” we don’t just survey birds and mammals. We do a lot of sampling of the water and plankton.

Wing on Fulmar — Wing at rail of the R/V Fulmar

We use a CTD (Conductivity – Temperature – Depth profiler) at every place we stop. We hook it to a cable, turn it on, and lower to down until it comes within 5-10 meters of the bottom. When we pull it back up, it has a continuous and digital record of water conductivity (a proxy for salinity, since salty water conducts electricity better), temperature, dissolved oxygen, fluorescence (a proxy for chlorophyll, basically phytoplankton), all as a function of depth.

We also have a Niskin bottle attached to the CTD cable. This is a sturdy plastic tube with stoppers at both ends. The tube is lowered into the water with both ends cocked open. When it is at the depth you want, you clip a “messenger” to the cable. The messenger is basically a heavy metal bead. You let go, it slides down the cable, and when it strikes a trigger on the Niskin bottle the stoppers on both ends snap shut. You can feel a slight twitch on the ship’s cable when this happens. You pull it back up and decant the seawater that was trapped at that depth into sample bottles to measure nitrate, phosphate, alkalinity, and other chemical parameters back in the lab.

When we want surface water, we just use a bucket on a rope of course.

We use a hoop net to collect krill and other zooplankton. We tow it behind the boat at a depth of about 50 meters, haul it back in, and wash the contents into a sieve, then put them in sample bottles with a little preservative for later study. We also have a couple of smaller plankton nets for special projects, like the University of California at Davis graduate student Kate Davis’s project on ocean acidification, and the plankton samples we send to the California Department of Health. They are checking for red tides.

We use a Tucker Trawl once a day on even numbered lines. This is a heavy and complicated rig that has three plankton nets, each towed at a different depth. It takes about an hour to deploy and retrieve this one; that’s why we don’t use it each time we stop. The Tucker trawl is to catch krill; which are like very small shrimp. During the day they are down deep; they come up at night.

A mass of krill we collected. The black dots are their eyes.

What happens to these samples? The plankton from the hoop net gets sent to a lab where a subsample is taken and each species in the subsample is counted very precisely. The CTD casts are shared by all the groups here – NOAA, Point Blue Conservation Science, the University of California at Davis, San Francisco State University. The state health department gets its sample. San Francisco State student Ryan Hartnett has some water samples he will analyze for nitrate, phosphate and silicate. All the data, including the bird and mammal sightings, goes into a big database that’s been kept since 2004. That’s how we know what’s going on in the California Current. When things change, we’ll recognize the changes.

Personal Log

They told me “wear waterproof pants and rubber boots on the back deck, you’ll get wet.” I thought, how wet could it be? Now I understand. It’s not that some water drips on you when you lift a net up over the stern of the boat – although it does. It’s not that waves splash you, although that happens too. It’s that you use a salt water hose to help wash all of the plankton from the net into a sieve, and then into a container, and to fill wash bottles and to wash off the net, sieve, basins, funnel, etc. before you arrive at the next station and do it all again. It takes time, because you have to wash ALL of the plankton from the end of the net into the bottle, not just some of it. You spend a lot of time hosing things down. It’s like working at a car wash except with salty water and the deck is pitching like a continuous earthquake.

The weather has gone back to “normal”, which today means 15 knot winds gusting to 20 knots, wind waves 3-5’ and a northwest swell 3-4’ only four seconds apart. Do the math, and you’ll see that occasionally a wind wave adds to a swell and you get slapped by something eight feet high. We were going to go to Bodega Bay today; we had to return to Sausalito instead because it’s downwind.

The sea state today. Some waves were pretty big.

We saw a lot of humpback whales breaching again and again, and slapping the water with their tails. No, we don’t know why they do it although it just looks like fun. No, I didn’t get pictures. They do it too fast.

Did You Know? No biologist or birder uses the word “seagull.” They are “gulls”, and there are a lot of different species such as Western gulls, California gulls, Sabine’s gulls and others. Yes, it is possible to tell them apart.

May 28, 2015August 21, 2021

DJ Kast, Interview with Megan Switzer and the Basics of the CTD/ Rosette, May 28, 2015

NOAA Teacher at Sea
Dieuwertje “DJ” Kast
Aboard NOAA Ship Henry B. Bigelow
May 19 – June 3, 2015

Mission: Ecosystem Monitoring Survey
Geographical area of cruise: Gulf of Maine
Date: May 28, 2015, Day 11 of Voyage

Interview with Student Megan Switzer

Chief Scientists Jerry Prezioso and graduate oceanography student Megan Switzer — Chief Scientist Jerry Prezioso and graduate oceanography student Megan Switzer

Megan Switzer is a Masters student at the University of Maine in Orono. She works in Dave Townsend’s lab in the oceanography department. Her research focuses on interannual nutrient dynamics in the Gulf of Maine. On this research cruise, she is collecting water samples from Gulf of Maine, as well as from Georges Bank, Southern New England (SNE), and the Mid Atlantic Bight (MAB). She is examining the relationship between dissolved nutrients (like nitrate and silicate) and phytoplankton blooms. This is Megan’s first research cruise!

In the generic ocean food chain, phytoplankton are the primary producers because they photosynthesize. They equate to plants on land. Zooplankton are the primary consumers because they eat the phytoplankton. There are so many of both kinds in the ocean. Megan is focusing on a particular phytoplankton called a diatom; it is the most common type of phytoplankton found in our oceans and is estimated to contribute up to 45% of the total oceanic primary production (Yool & Tyrrel 2003). Diatoms are unicellular for the most part, and a unique feature of diatom cells is that they are enclosed within a cell wall made of silica called a frustule.

Diatom Frustules. Photo by: 3-diatom-assortment-sems-steve-gschmeissner — Diatom Frustules. Photo by: Steve Schmeissner

Diatoms! PHOTO BY: — Diatoms! Photo by: Micrographia

The frustules are almost bilaterally symmetrical which is why they are called di (2)-atoms. Diatoms are microscopic and they are approximately 2 microns to about 500 microns (0.5 mm) in length, or about the width of a human hair. The most common species of diatoms are: Pseudonitzchia, Chaetocerous, Rhizosolenia, Thalassiosira, Coschinodiscus and Navicula.

Pseudonitzchia. Photo by National Ocean Service

Thalassiosira. Photo by: Department of Energy Joint Genome Institute

Photo of Coscinodiscus by: — Photo of Coscinodiscus

Diatoms also have ranges and tolerances for environmental variables, including nutrient concentration, suspended sediment, and flow regime. As a result, diatoms are used extensively in environmental assessment and monitoring. Furthermore, because the silica cell walls are inorganic substances that take a long time to dissolve, diatoms in marine and lake sediments can be used to interpret conditions in the past.

In the Gulf of Maine, the seafloor sediment is constantly being re-suspended by tidal currents, bottom trawling, and storm events, and throughout most of the region there is a layer of re-suspended sediment at the bottom called the Bottom Nepheloid Layer. This layer is approximately 5-30 meters thick, and this can be identified with light attenuation and turbidity data. Megan uses a transmissometer, which is an instrument that tells her how clear the water is by measuring how much light can pass through it. Light attenuation, or the degree to which a beam of light is absorbed by stuff in the water, sharply increases within the bottom nepheloid layer since there are a lot more particles there to block the path of the light. She also takes a water sample from the Benthic Nepheloid Layer to take back to the lab.

Marine Silica Cycle by Sarmiento and Gruber 2006

Megan also uses a fluorometer to measure the turbidity at various depths. Turbidity is a measure of how cloudy the water is. The water gets cloudy when sediment gets stirred up into it. A fluorometer measures the degree to which light is reflected and scattered by suspended particles in the water. Taken together, the data from the fluorometer and the transmissometer will help Megan determine the amount of suspended particulate material at each station. She also takes a water sample from the Benthic Nepheloid layer to take back to the lab. There, she can analyze the suspended particles and determine how many of them are made out of the silica based frustules of sinking diatoms.

This instrument is a Fluorometer and is used to measure the turbidity at various depths. Photo by: DJ Kast

She collects water at depth on each of the CTD/ Rosette casts.

Rosette with the 12 Niskin Bottles and the CTD. Photo by DJ Kast

Up close shot of the water sampling. Photo by DJ Kast

CTD, Rosette, and Niskin Bottle basics.

The CTD or (conductivity, temperature, and depth) is an instrument that contains a cluster of sensors, which measure conductivity, temperature, and pressure/ depth.

Here is a video of a CTD being retrieved.

Depth measurements are derived from measurement of hydrostatic pressure, and salinity is measured from electrical conductivity. Sensors are arranged inside a metal housing, the metal used for the housing determining the depth to which the CTD can be lowered. Other sensors may be added to the cluster, including some that measure chemical or biological parameters, such as dissolved oxygen and chlorophyll fluorescence. Chlorophyll fluorescence measures how many microscopic photosynthetic organisms (phytoplankton) are in the water. The most commonly used water sampler is known as a rosette. It is a framework with 12 to 36 sampling Niskin bottles (typically ranging from 1.7- to 30-liter capacity) clustered around a central cylinder, where a CTD or other sensor package can be attached. The Niskin bottle is actually a tube, which is usually plastic to minimize contamination of the sample, and open to the water at both ends. It has a vent knob that can be opened to drain the water sample from a spigot on the bottom of the tube to remove the water sample. The scientists all rinse their bottles three times and wear nitrile or nitrogen free gloves to prevent contamination to the samples.

On NOAA ship Henry B. Bigelow the rosette is deployed from the starboard deck, from a section called the side sampling station of this research vessel.

The instrument is lowered into the water with a winch operated by either Adrian (Chief Boatswain- in charge of deck department) or John (Lead Fishermen- second in command of deck department). When the CTD/Rosette is lowered into the water it is called the downcast and it will travel to a determined depth or to a few meters above the ocean floor. There is a conducting wire cable is attached to the CTD frame connecting the CTD to an on board computer in the dry lab, and it allows instantaneous uploading and real time visualization of the collected data on the computer screen.

CTD data on the computer screen. Photo by: DJ Kast

The water column profile of the downcast is used to determine the depths at which the rosette will be stopped on its way back to the surface (the upcast) to collect the water samples using the attached bottles.

Niskin Bottles:

Messenger- The manual way to trigger the bottle is with a weight called a messenger. This is sent down a wire to a bottle at depth and hits a trigger button. The trigger is connected to two lanyards attached to caps on both ends of the bottle. When the messenger hits the trigger, elastic tubing inside the bottle closes it at the specified depth.

Todd with the manually operated Niskin Bottle. Photo by: DJ Kast — Todd holding a messenger to trigger the manually operated Niskin Bottle. Photo by: DJ Kast

Manual CTD fully cocked and ready to deploy. Photo by DJ Kast

Here is a video of how the manual niskin bottle closes: https://www.youtube.com/watch?v=qrqXWtbUc74

The other way to trigger Niskin bottles is electronically. The same mechanism is in place but an electronic signal is sent down the wire through insulated and conductive sea cables (to prevent salt from interfering with conductivity) to trigger the mechanism.

Here is a video of how it closes electronically: https://www.youtube.com/watch?v=YJF1QVe6AK8

Conductive Wire to CTD. Photo by DJ Kast

Photo of the top of the CTD. Photo by DJ Kast — Photo of the top of the CTD showing the trigger mechanism in the center. Photo by DJ Kast

Top of the Niskin Bottles to show how the white wires are connected to the top. — Top of the Niskin Bottles shows how the lanyards are connected to the top. Photo by DJ Kast

The pin on the bottom is activated when an electronic signal is sent through the conductive sea cables. Photo by DJ Kast

Using the Niskin bottles, Megan collects water samples at various depths. She then filters water samples for her small bottles with a syringe and a filter and the filter takes out the phytoplankton, zooplankton and any particulate matter. She does this so that there is nothing living in the water sample, because if there is there will be respiration and it will change the nutrient content of the water sample.

Filtering out only the water using a syringe filter. Photo by DJ Kast

Syringe with a filter on it. Photo by: DJ Kast

This is part of the reason why we freeze the sample in the -80 C fridge right after they have been processed so that bacteria decomposing can’t change the nutrient content either.

Diatoms dominate the spring phytoplankton bloom in the Gulf of Maine. They take up nitrate and silicate in roughly equal proportions, but both nutrients vary in concentrations from year to year. Silicate is almost always the limiting nutrient for diatom production in this region (Townsend et. al., 2010). Diatoms cannot grow without silicate, so when this nutrient is used up, diatom production comes to a halt. The deep offshore waters that supply the greatest source of dissolved nutrients to the Gulf of Maine are richer in nitrate than silicate, which means that silicate will be used up first by the diatoms with some nitrate left over. The amount of nitrate left over each year will affect the species composition of the other kinds of phytoplankton in the area (Townsend et. al., 2010).

The silica in the frustules of the diatom are hard to breakdown and consequently these structures are likely to sink out of the euphotic zone and down to the seafloor before dissolving. If they get buried on the seafloor, then the silicate is taken out of the system. If they dissolve, then the dissolved silicate here might be a source of silicate to new production if it fluxes back to the top of the water column where the phytoplankton grow.

Below are five images called depth slices. These indicate the silicate concentration (rainbow gradient) over a geographical area (Gulf of Maine) with depth (in meters) latitude and longitude on the x and y axis.

Depth slices of nitrate and silicate. Photo by: This is the type of data Megan is hoping to process from this cruise. — Depth slices of nitrate and silicate. Photo by: GOMTOX at the University of Maine
This is the type of data Megan is hoping to process from this cruise.

May 22, 2015August 21, 2021

DJ Kast, Interview with Jessica Lueders-Dumont, May 22, 2015

NOAA Teacher at Sea
Dieuwertje “DJ” Kast
Aboard NOAA Ship Henry B. Bigelow
May 19 – June 3, 2015

Mission: Ecosystem Monitoring Survey
Geographical area of cruise: East Coast
Date: May 22, 2015, Day 4 of Voyage

Interview with Jessica Lueders-Dumont

Who are you as a scientist?

Jessica Lueders-Dumont is a graduate student at Princeton University and has two primary components of her PhD — nitrogen biogeochemistry and historical ecology of the Gulf of Maine.

Jessica Lueders- Dumont, graduate student at Princeton cleaning a mini bongo plankton net for her sample. Photo by: DJ Kast

What research are you doing?

Her two projects are, respectively,

A) Nitrogen cycling in the North Atlantic (specifically focused on the Gulf of Maine and on Georges Bank but interested in gradients along the entire eastern seaboard)

B) Changes in trophic level of Atlantic cod in the Gulf of Maine and on Georges Bank over the history of fishing in the region. The surprising way in which these two seemingly disparate projects are related is that part A effectively sets the baseline for understanding part B!

She is co-advised by Danny Sigman and Bess Ward. Danny’s research group focuses on investigating climate change through deep time, primarily by assessing changes in the global nitrogen cycle which are inextricably tied to the strength of the biological pump (i.e. biological-mediated carbon export and storage in the ocean). Bess’s lab focuses on the functional diversity of marine phytoplankton and bacteria and the contributions of these groups to various nitrogen cycling processes in the modern ocean, specifically as pertains to oxygen minimum zones (OMZs). She is also advised by a Olaf Jensen, a fisheries scientist at Rutgers University.

In both of these biogeochemistry labs, nitrogen isotopes (referred to as d15N, the ratio of the heavy 15N nuclide to the lighter 14N nuclide in a sample compared to that of a known standard) are used to track nitrogen cycling processes. The d15N of a water mass is a result of the relative proportions of different nitrogen cycling processes — nitrogen fixation, nitrogen assimilation, the rate of supply, the extent of nutrient utilization, etc. These can either be constrained directly via 15N tracer studies or can be inferred from “natural abundance” nitrogen isotopic composition, the latter of which will be used as a tool for this project.

Nitrogen Cycle in the Ocean. Photo credit to: https://wordsinmocean.files.wordpress.com/2012/02/n-cycle.png

On this cruise she has 3 sample types — phytoplankton, zooplankton, and seawater nitrate — and two overarching questions that these samples will address: How variable is “baseline d15N” along the entire eastern seaboard, and does this isotopic signal propagate to higher trophic levels? Each sample type gives us a different “timescale” of N cycling on the U.S. continental shelf. She will be filtering phytoplankton from various depths onto filters, she will be collecting seawater for subsequent analysis in the lab, and she will be collecting zooplankton samples — all of which will be analyzed for nitrogen isotopic composition (d15N).

Biogeochemistry background:

Biogeochemists look at everything on an integrated scale. We like to look at the box model, which looks at the surface ocean and the deep ocean and the things that exchange between the two.

The surface layer of the ocean: euphotic zone (approximately 0-150 m-but this range depends on depth and location and is essentially the sunlit layer); nutrients are scarce here.

When the top zone animals die they sink below the euphotic zone and into the aphotic zone (150 m-4000m), and the bacteria break down the organic matter into inorganic matter (nitrate (NO3), phosphate (PO4) and silicate (Si(OH)3.). In terms of climate, an important nutrient that gets cycled is carbon dioxide.We look at the nitrate, phosphate, and silicate as limiting factors for biological activity for carbon dioxide, we are essentially calculating these three nutrients to see how much carbon dioxide is being removed from the atmosphere and “pumped” into the deep sea. This is called the biological pump. Additionally, the particulate matter that falls to the deep sea is called Marine Snow, which is tiny organic matter from the euphotic zone that fuels the deep sea environments; it is orders of magnitude less at the bottom compared to the top.

Cycling — Visual Representation of the aphotic and euphotic zones and the nutrients that cycle through them. Photo by: Patricia Sharpley

Did you know that the “Deep sea is really acidic, holds a lot of CO2 and is the biggest reservoir of C02 in the world?” – From Jessica Lueders- Demont, graduate student at Princeton.

One of the most important limiting factors for phytoplankton is nitrogen, which is not readily available in many parts of the global ocean. “A limiting nutrient is a chemical necessary for plant growth, but available in quantities smaller than needed for algae and other primary producers to increase their abundance. Organisms can grow and reproduce only when they have sufficient nutrients. For algae, the carbon source is CO₂and this, at least in the surface water, has a constant value and is not limiting their growth. The limiting nutrients are minerals (such as Fe⁺²), nitrogen, and phosphorus compounds” (Patricia Sharpley 2010).

Conversely, phosphorus is the limiting factor on land. The most common nitrogen is molecular nitrogen or N2, which has a strong bond to break and biologically it is very expensive to fix from the atmosphere.

Biological, chemical, and physical oceanography all work together in this biogeochemistry world and are needed to have a productive ocean. For example, we need the physical oceanography to upwell them to the surface so that the life in the euphotic zone can use them.

Activities on the ship that I am assisting Jessica with:

Zooplankton collected using mini bongos with a 165 micron mesh and then further filtered at meshes: 1000, 500, and ends with 250 microns, this takes out all of the big plankton that she is not studying and leaves only her own in her size range which is 165-200 microns.
She is collecting zooplankton water samples because it puts the phytoplankton that she is focusing on into perspective.

The last of the mesh buckets that's filtering for phytoplankton. Photo by: DJ Kast — The last of the mesh buckets that’s filtering for phytoplankton. Photo by: DJ Kast

- Aspirator pump sucks out all of the water so that the zooplankton are left on a glass fiber filter (GFFs) on the filtration rack.

Aspirator pump that is on the side sucks out all of the air so that the plankton get stuck on the filters at the bottom of the cups seen here. Photo by: DJ Kast
Bottom of the cup after all the water has been sucked through. Photo by: DJ Kast
Jessica removing the filter with sterilized tweezers to place into a labeled petri dish. Photo by: DJ Kast

Labeled petri dish with GFF of phytoplankton on it. Photo by: DJ Kast

Video of this happening:

Phytoplankton filtering:

Jessica collecting her water sample from the Niskin bottle in the Rosette. Photo by DJ Kast

Up close shot of the spigot that releases water from Niskin bottle in the Rosette. Photo by DJ Kast

DJ Kast helping Jessica collect her 4 L of seawater from the Niskin bottle in the Rosette. Photo by Jerry P.

DJ and Jessica collect her 4 L of seawater from the Niskin bottle in the Rosette. Photo by Jerry P.

Chief Scientist Jerry Prezioso and Megan Switzer next to the CTD and Rosette Photo by: DJ Kast

May 21, 14:00 hours: Phytoplankton filtering with Jessica.

In addition to the small bottles Jessica needs, we filled 4 L bottles with water at the 6 different depths (100, 50, 30, 20, 10, 3 m) as well.

We then brought all the 4 L jugs into the chemistry lab to process them. The setup includes water draining through the tubing coming from the 4 L jugs into the filters with the GFFs in it. Each 4 L jug is filtered by 2 of these filter setups preferably at an equal rate. The deepest depth 100 m was finished the quickest because it had the least amount of phytoplankton that would block the GFF and then a second jug was collected to try and increase the concentration of phytoplankton on the GFF.

Phytoplankton filtration setup. Photo by DJ Kast

The filter and pump setup up close. Photo by DJ Kast

Up close shot of the GFF within the filtration unit. Photo by DJ Kast

Jessica keeping an eye on her filtration system to make sure nothing is leaking and that there are no air bubbles restricting water flow. Photo by DJ Kast

Here I am helping Jessica setup the filtration unit.Photo by Jessica Lueders- Dumont

The GFF with the phytoplankton (green stuff) on it. Photo by: DJ Kast

There are 2 filters for each depth, and since she has 12 filtration bottles total, then she would be collecting data from 6 depths. She collects 2 filters so that she has replicates for each depth.

Here they are all laid out to show the differences in phytoplankton concentration.

The 6 depths worth of GFFs. See how the 30 m is the darkest. Thats evidence for the chlorophyll max. Photo by: DJ Kast

She will fold the GFF in half in aluminum foil and store it at -80C until back in the lab at Princeton. There, the GFF’s are combusted in an elemental analyzer and the resulting gases run through a mass spectrometer looking for concentrations of N2 and CO2. The 30 m GFF was the most concentrated and that was because of a chlorophyll maximum at this depth.

Chlorophyll maximum layers are common features of vertically stratified water columns. There is a subsurface maximum or layer of chlorophyll concentration. These are found throughout oceans, lakes, and estuaries around the world at varying depths, thicknesses, intensities, composition, and time of year.

April 1, 2015August 21, 2021

Julia West: This Is What Drives Us, April 1, 2015

NOAA Teacher at Sea
Julia West
Aboard NOAA ship Gordon Gunter
March 17 – April 2, 2015

Mission: Winter Plankton Survey
Geographic area of cruise: Gulf of Mexico
Date: April 1, 2015

Weather Data from the Bridge

Date: 3/31/2015; Time 2000; clouds 25%, cumulus and cirrus; Wind 205° (SSW), 15 knots; waves 1-2 ft; swells 1-2 ft; sea temp 23°C; air temp 23°C

Science and Technology Log

You’re not going to believe what we caught in our neuston net yesterday – a giant squid! We were able to get it on board and it was 23 feet long! Here’s a picture from after we released it:

April Fools! (sorry, couldn’t resist) The biggest squid we’ve caught are about a half inch long. Image from http://www.factzoo.com/.

Let’s talk about something just as exciting – navigation. I visit the bridge often and find it all very interesting, so I got a 30 minute crash course on navigation. We joked that with 30 minutes of training, yes, we would be crashing!

From the bridge, you can see a long way in any direction. The visible range of a human eye in good conditions is 10 miles. Because the earth is curved, we can’t see that far. There is a cool little formula to figure out how far you can see. You take the square root of your “height of eye” above sea level, and multiply that by 1.17. That gives you the nautical miles that you can see.

So the bridge is 36 feet up. “Really?” I asked Dave. He said, “Here, I’ll show you,” and took out a tape measure.

Dave measuring height — ENS Dave Wang measuring the height of the bridge above sea level.

OK, 36 feet it is, to the rail. Add a couple of feet to get to eye level. 38 feet. Square root of 38 x 1.17, and there we have it: 7.2 nautical miles. That is 8.3 statute miles (the “mile” we are used to using). That’s assuming you are looking at something right at sea level – say, a giant squid at the surface. If something is sticking up from sea level, like a boat, that changes everything. And believe me, there are tables and charts to figure all that out. Last night the bridge watch saw a ship’s light that was 26 miles away! The light on our ship is at 76 feet, so they might have been able to see us as well.

Challenge Yourself

If you can see 7.2 nautical miles in any direction, what is the total area of the field of view? It’s a really amazing number!

Back to navigation

Below are some photos of the navigation charts. They can be zoomed in or out, and the officers use the computer to chart the course. You can see us on the chart – the little green boat.

In the chart above, you’ll see that we seem to be off course. Why? Most likely because of that other ship that is headed our direction. We talk to them over the radio to get their intentions, and reroute our course accordingly.

navigation chart 2 — Notice the left side, where it says “dump site (discontinued) organochlorine waste. There are a lot of these type dump sites in the Gulf. Just part of the huge impact humans have had on our oceans.

When we get close to a station, as in the first picture above, the bridge watch team sets up a circle with a one mile radius around the location of the station. See the circle, upper center? We need to stay within that circle the whole time we are collecting our samples. With the bongos and the neuston net, the ship is moving slowly, and with the CTD the ship tries maintain a stationary position. However, wind and current can affect the position. These factors are taken into account before we start the station. The officer on the bridge plans out where to start so that we stay within the circle, and our gear that is deployed doesn’t get pushed into or under the boat. It’s really a matter of lining up vectors to figure it all out – math and physics at work. But what is physics but an extension of common sense? Here’s a close-up:

setting up for station — Here is the setup for the station. The plan is that we will be moving south, probably into the wind, during the sampling. See the north-south line?

How do those other ships appear on the chart? This is through input from the AIS (Automated Information System), through which we can know all about other ships. It broadcasts their information over VHF radio waves. We know their name, purpose, size, direction, speed, etc. Using this and the radar system, we can plan which heading to take to give the one-mile distance that is required according to ship rules.

As a backup to the computer navigation system, every half hour, our coordinates are written on the (real paper) navigation chart, by hand.

Pete charting our course — ENS Pete Gleichauf is writing our coordinates on the paper navigation chart.

There are drawers full of charts for everywhere the Gunter travels!

Melissa and the nav charts — ENS Melissa Mathes showing me where all the navigation charts are kept. Remember, these are just backups!

Below is our radar screen. There are 3 other ships on the screen right now. The radar computer tells us the other vessels’ bearing and speed, and how close they will get to us if we both maintain our course and speed.

If the radar goes down, the officers know how to plot all this on paper.

On this maneuvering board, officers are trained to plot relative positions just like the radar computer does.

Below is Dave showing me the rudder controls. The rudder is set to correct course automatically. It has a weather adjustment knob on it. If the weather is rough (wind, waves, current), the knob can allow for more rudder correction to stay on course. So when do they touch the wheel? To make big adjustments when at station, or doing course changes.

These are the propulsion control throttles – one for each propeller. They control the propeller speed (in other words, the ship’s speed).

propeller speed throttles — Here are the throttles that control the engine power, which translates to propeller speed.

bow thruster control — This controls the bow thruster, which is never used except in really tight situations, such as in port. It moves the bow either direction.

And below is the Global Maritime Distress and Safety System (GMDSS). It prints out any nautical distress signal that is happening anywhere in the world!

And then, of course, there is a regular computer, which is usually showing the ships stats, and is connected to the network of computers throughout the ship.

ENS Kristin Johns checking the weather system coming our way.

In my post of March 17, I described the gyrocompass. That is what we use to determine direction, and here is a rather non-exciting picture of this very important tool.

As you can see, we have two gyrocompasses, but since knowing our heading is probably the most important thing on the ship, there are backup plans in place. With every watch (every 4 hours), the gyro compass is aligned the magnetic compass to determine our declination from true north. Also, once per trip, the “gyro error” is calculated, using this nifty device:

The reading off of the alidade, combined with the exact time, coordinates, and some fancy math, will determine the gyro error. (Click on a picture to see full captions and full size pictures.)

The math for calculating gyro error isn’t hard; it just takes many steps and careful following of instructions!

Numbers need to be taken from charts in these books…

Knowing how to read charts and tables is important!

You can see that we have manual backups for everything having to do with navigation. We won’t get lost, and we’ll always know where we are!

driving the ship — Here I am, “driving” the ship! Watch out! Photo by ENS Pete Gleichauf

Back to Plankton!

These past two days, we have been in transit, so no sampling has been done. But here are a couple more cool micrographs of plankton that Pam shared with me.

invertebrate plankton — This picture shows several invertebrates, along with fish eggs. Madalyn and Andy, who are invertebrate people, got excited at this collection. The fat one, top left is a Doliolid. The U-shaped one is a Lucifer shrimp, the long one in center is an amphipod, at the bottom is a mycid, etc. There are crabs in different stages of development, and the multiple little cylinders are copepods! You can also see the baby fish inside the eggs. Photo credit Pamela Bond/NOAA

red snapper larvae — These are larval red snapper, a fall spawning fish species of economic interest. Notice the scale! You have to admit baby fish are awfully cute. Photo credit: Pamela Bond/NOAA

Interesting Fish Facts

Our main fish of interest in the winter plankton sampling are the groupers. There are two main species: gag groupers and red groupers. You can learn all about them on the NOAA FishWatch Website. Groupers grow slowly and live a long time. Interestingly, some change from female to male after about seven years – they are protogynous hermaphrodites.

In the spring plankton research cruise, which goes out for all of May, the main species of interest is the Atlantic bluefin tuna. This species can reach 13 feet long and 2000 lbs, and females produce 10 million eggs a year!

school of bluefin tuna — School of Atlantic bluefin tuna. Photo credit: NOAA

The fall plankton research focuses on red snapper. These grow up to about 50 pounds and live a long time. You can see from the map of their habitat that it is right along the continental shelf where the sampling stations are.

The NOAA FishWatch website is a fantastic resource, not only to learn about the biology, but about how they are managed and the history of each fishery. I encourage you to look around. You can see that all three of these fish groups have been overfished, and because of careful management, and research such as what we are doing, the stocks are recovering – still a long way from what they were 50 years ago, but improving.

I had a good question come in: how long before the fish larvae are adults? Well, fish are interesting creatures; they are dependent on the conditions of their environment to grow. Unlike us, fish will grow throughout their life! Have you ever kept goldfish in an aquarium or goldfish bowl? They only grow an inch or two long, right? If you put them in an outdoor pond, you’ll see that they will grow much larger, about six inches! It all depends on the environment (combined with genetics).

“Adult” generally means that they are old enough to reproduce. That will vary by species, but with groupers, it is around 4 years. They spawn in the winter, and will remain larvae for much longer than other fish, because of the cooler water.

Personal Log

I’ve used up my space in this post, and didn’t even get to tell you about our scientists! I will save that for next time. For now, I want to share just a few more pictures of the ship. (Again, click on one to get a slide show.)

This is the bridge deck – inside those windows are where most of the pictures on this post were taken. The flying bridge is above.

This is looking forward (and very far down) from the flying bridge toward the bow.

This is the Gunter, looking aft from the flying bridge

My favorite part of the ship – the flying bridge. It’s the highest and a wonderful place for an afternoon nap or to read a book.

We have a small gym on board with an elliptical, treadmill, bike, free weights, a rowing machine, and other goodies. I use it often – I like to do the hill climb on the treadmill or ride the bike.

This is the lounge where people sometimes watch movies

Terms to Learn

What is the difference between a nautical mile and a statute mile? How about a knot?

Do you know what I mean when I say “invertebrate?” It is an animal without a backbone. Shrimp and crabs, are invertebrates; we are vertebrates!

March 30, 2015August 21, 2021

Julia West: Science Is About the Details, March 29, 2015

NOAA Teacher at Sea
Julia West
Aboard NOAA ship Gordon Gunter
March 17 – April 2, 2015

Mission: Winter Plankton Survey
Geographic area of cruise: Gulf of Mexico
Date: March 29, 2015

Weather Data from the Bridge

Time 1600; clouds 35%, cumulus; wind 170 (S), 18 knots; waves 5-6 ft; sea temp 24°C; air temp 23°C

Science and Technology Log

We have completed our stations in the western Gulf! Now we are steaming back to the east to pick up some stations they had to skip in the last leg of the research cruise, because of bad weather. It’s going to be a rough couple of days back, with a strong south wind, hence the odd course we’re taking (dotted line). Here’s the updated map:

sampling stations 3/29/15 — Here’s where we are as of the afternoon of 3/29 (the end of the solid red line. We’ve connected all the dots!

I had a question come up: How many types of plankton are there? Well, that depends what you call a “type.” This brings up a discussion on taxonomy and Latin (scientific) names. The scientists on board, especially the invertebrate scientists, often don’t even know the common name for an organism. Scientific names are a common language used everywhere in the world. A brief look into taxonomic categories will help explain. When we are talking about numbers, are we talking the number of families? Genera? Species? Sometimes all that is of interest are the family names, and we don’t need to get more detailed for the purposes of this research. Sometimes specific species are of interest; this is true for fish and invertebrates (shrimp and crabs) that we eat. Suffice it to say, there are many, many types of plankton!

Another question asks what the plankton do at night, without sunlight. Phytoplankton (algae, diatoms, dinoflagellates – think of them like the plants of the sea) are the organisms that need sunlight to grow, and they don’t migrate much. The larval fish are visual feeders. In a previous post I explained that they haven’t developed their lateral line system yet, so they need to see to eat. They will stay where they can see their food. Many zooplankton migrate vertically to feed during the night when it is safer, to avoid predators. There are other reasons for vertical migration, such as metabolic reasons, potential UV light damage, etc.

Vertical migration plays a really important role in nutrient cycling. Zooplankton come up and eat large amounts of food at night, and return to the depths during the day, where they defecate “fecal pellets.” These fecal pellets wouldn’t get to the deep ocean nearly as fast if they weren’t transported by migrating zooplankton. Thus, migration is a very important process in the transport of nutrients to the deep ocean. In fact, one of the most voracious plankton feeders are salps, and we just happened to catch one! Salps will sink 800 meters after feeding at night!

Salp caught in the neuston sample. Salps are a colony of tunicates (invertebrate chordates for you biology students – more closely related to humans than shrimp are!)

Now it’s time to go back into the dry lab and talk about what happens in there. I’ll start with the chlorophyll analysis. In the last post I described fluorescence as being an indicator of chlorophyll content. What exactly is fluorescence? It is the absorption and subsequent emission of light (usually of a different wavelength) by living or nonliving things. You may have heard the term phosphorescence, or better yet, seen the waves light up with a beautiful mysterious light at night. Fluorescence and phosphorescence are similar, but fluorescence happens simultaneously with the light absorption. If it happens after there is no light input (like at night), it’s called phosphorescence.

An example of phosphorescence. We haven’t seen it yet, but I hope to! (From eco-adventureholidays.co.uk)

Well, it is not just phytoplankton that fluoresce – other things do also, so to get a more accurate assessment of the amount of phytoplankton, we measure the chlorophyll-a in our niskin bottle samples. Chlorophyll-a is the most abundant type of chlorophyll.

We put the samples in dark bottles. Light allows photosynthesis, and when phytoplankton (or plants) can photosynthesize, they can grow. We don’t want our samples to change after we collect them. For this same reason, we also process the samples in a dark room. I won’t be able to get pictures of the work in action, but here are some photos of where we do this.

chlorophyll lab — This is the room where we do the chlorophyll readings.

We filter the chlorophyll out of the samples using this vacuum filter:

chlorophyll filter — Each of these funnels filters the sea water through a very fine filter paper to capture the chlorophyll.

The filter papers are placed in test tubes with methanol, and refrigerated for 24 hours or so. Then the test tubes are put in a centrifuge to separate the chlorophyll from the filter paper.

filter paper for chlorophyll — Some of the test tubes for chlorophyll readings, and the filter paper. This box costs about $100!

The chlorophyll values are read in this fancy machine. Hopefully the values will be similar to those values obtained during the CTD scan. I’ll describe that next.

Fluorometer — This fluorometer reads chlorophyll levels.

While the nets and CTD are being deployed and recovered, one person in the team is monitoring and controlling the whole event on the computer. I got to be this person a few times, and while you are learning, it is stressful! You don’t want to forget a step. Telling the winch operator to stop the bongos or CTD just above the bottom (and not hit bottom) is challenging, as is capturing the “chlorophyll max” by stopping the CTD at just the right place in the water column.

Bongo graph — This is the graph that comes back from the SeaCAT on the bongo. We are interested in the green line, which shows depth as it goes down and comes back up.

The dry lab — Here I am trying my hand at the computers. The monitor on the left is the live video of what is happening on deck (see the neuston net?). Photo by A.L. VanCampen

CTD scan — This is the CTD graph after it has been completed. The left (magenta) line is the chlorophyll, and the horizontal red lines are where we have fired a bottle and collected a sample. Notice the little spike partway down. That is the chlorophyll max, and we try to capture that when bringing it back up. The colored chart shows columns of continuous data coming in.

Here’s another micrograph of larval fish. Notice the tongue fish, the big one on the right. It is a flatfish, related to flounder. See the two eyes on one side of its head? Flatfish lie on the bottom, and have no need for an eye facing the bottom. When they are juveniles, they have an eye on each side, and one of the eyes migrates to the other side, so they have two eyes on one side! Be sure to take the challenge in the caption!

Larval fish 2 — There is a cutlass fish just right of center. Can you find the other one? How about the lizard fish? Hint – look back at the picture in the last post. Photo credit Pamela Bond/NOAA

Personal Log

It’s time to introduce our intrepid leader, Commanding Officer Donn Pratt, known as CO around here. CO lives (when not aboard the Gunter) in Bellingham, WA. He got his start in boats as a kid, starting early working on crab boats. He spent 9 years with the US Coast Guard, where he had a variety of assignments. In 2001, CO transferred to NOAA, while simultaneously serving in the US Navy Reserve. CO is not a commissioned NOAA officer; he went about his training in a different way, and is one of two US Merchant Marine Officers in the NOAA fleet. He worked as XO for about seven years on various ships, and last year he became CO of the Gordon Gunter.

CO is well known on the Gunter for having strong opinions, especially about food and music. He loves being captain for fish research, but will not eat fish (nor sweet potatoes for that matter). A common theme of meal conversations is music; CO plays drums and guitar and is a self-described “music snob.” We have fun talking about various bands, new and old.

CO Donn Pratt — CO Don Pratt on the bridge.

One of the most experienced and highly respected of our crew is Jerome Taylor, our Chief Boatswain (pronounced “bosun”). Jerome is the leader of the deck crew. He keeps things running smoothly. As I watch Jerome walk around in his cheerful and hardworking manner, he is always looking, always checking every little thing. Each nut and bolt, each patch of rust that needs attention – Jerome doesn’t miss a thing. He knows this ship inside and out. He is a master of safety. As he teaches the newer guys how to run the winch, his mannerism is one of mutual respect, fun and serious at the same time.

Jerome has been with NOAA for 30 years now, and on the Gunter since NOAA acquired the ship in 1998. He lives right in Pascagoula, MS. I’ve only been here less than two weeks, but I can see what a great leader he is. When I grow up, I want to be like Jerome!

Challenge Yourself!

OK, y’all (yes, I’m in the south), I have a math problem for you! Remember, in the post where I described the bongos, I showed the flowmeter, and described how the volume of water filtered can be calculated? Let’s practice. The volume of water filtered is the area of the opening x the “length” of the stream of water flowing through the bongo.

V = area x length.

Remember how to calculate the area of a circle? I’ll let you review that on your own. The diameter (not radius) of a bongo net is 60 cm. We need the area in square meters, not cm. Can you make the conversion? (Hint: convert the radius to meters before you calculate.)

Now, that flow meter is just a counter that ticks off numbers as it spins. In order to make that a usable number, we need to know how much distance each “click” is. So we have R, the rotor constant. It is .02687m.

R = .02687m

Here’s the formula:

Volume(m³) = Area(m²) x R(F_e – F_s) m

F_e = Ending flowmeter value; F_s = Starting flowmeter value

The right bongo net on one of the stations this morning had a starting flowmeter value of 031002. The ending flowmeter value was 068242.

You take it from here! What is the volume of water that went through the right bongo net this morning? If you get it right, I’ll buy you an ice cream cone next time I see you! 🙂

April 16, 2014August 20, 2021

Kimberly Gogan: The Creatures That Are Always There but We Never See! April 15, 2014

NOAA Teacher at Sea
Kim Gogan
Aboard NOAA Ship Gordon Gunter
April 7 – May 1, 2014

Mission: AMAPPS & Turtle Abundance Survey, Ecosystem Monitoring
Geographical Area of Cruise: North Atlantic Ocean
Date: April 15, 2014

Weather Data from the Bridge
Air Temp: 14.1 degrees Celsius
Wind Speed:32 knots
Water Temp: 5.7 degrees Celsius
Water Depth: 24.5 meters

This is the Video Plankton Recorder that takes pictures and collects data of plankton.

This is a picture of planktonic crustaceans we were able to look at under a microscope after a deep bongo net tow on Georges Bank slope. Two are called Amphipods and the other is a Euphausiid commonly know as krill.

Betsy showing volunteer Brian and me the computer program that collects all the shots the VPR takes while it’s under water.

Science and Technology Log

Today’s blog is about a piece of equipment called a Video Plankton Recorder or VPR for short. The VPR is attached to the bottom of a yellow V-fin that helps it stay under water when it is being towed. Scientists would want to use a VPR instead of a Bongo Net because the Bongo Net is very rough on the creatures that are captured in it as it is towed through the water, especially the very, very soft and fragile ones. The VPR allows the scientists to capture pictures of the creatures in their natural habitat. It also allows them to get close-ups of these creatures so they can really see what their body structures look like. The VPR also allows the scientist to collect data on many creatures are found in a given area in the body of water they are looking at. The VPR has two arms, one on each side about 2 feet apart. One arm has a camera and the other arm has a strobe or flash. The camera and strobe focus on taking pictures between the arms at a rate of 20 pictures a second. The VPR captures all the images as it goes through the water and stores them on a disk drive that the scientists can then upload to their computers. The VPR is generally towed at a speed of around 2-3 knots , or 3-4 miles per hour.

Science Spot Light

The scientist in charge of running the VPR here on the Gordon Gunter is Betsy Broughton. Betsy is an Oceanographer who works on the night crew here on our ship. Betsy has been working on ships for 31 years and has been to sea for close to 1300 days on 18 ships including 3 international ships! When she isn’t on a ship she works at National Marine Fisheries Service (NMFS) in Woods Hole, Massachusetts. Betsy primarily studies baby Cod and Haddock. She is trying to understand how they survive when they are really little, before they look like a fish, what they eat, where they live and what eats them. If you want to learn more you can visit the Fish Facts on the NMFS webpage. Betsy also works on designing the sampling gear that will work faster and give scientists more accurate information. In her spare time, Betsy is an International Challenge Master for Challenge A with Destination Imagination.

This is a close up of the mouth of a Salp. These plankton are filter feeders.

This is a chain of Salps after they were born. They can be found linked together like this in chains or in singles.

This a Salp, which is a jelly-like Zooplankton. These are found in our coastal waters starting in the spring time.

This is called a Pleurobrancia otherwise commonly known as a Comb Jelly because of the rows of fine hairs they use to swim. They use the tentacles sticking out from the side to feed smaller plankton. We have been finding many of these in our bongo nets!

This is a Phoronid in a Salp body that it ate and is now using as a house. He will swim around in ts house and the females will lay their eggs in there. He is a predator with large claws. They will eat anything small that comes near their house. This tiny plankton was used as the model for the monsters in the movie “Alien.”

This is called a hydromedusa. It looks like a Jellyfish but it is much smaller and not a true jellyfish. Sometimes these can be found in a form attached to the bottom of the ocean floor at a certain time in their life. Like jellyfish they sting things that drift into their tentacles.

This is called a Clione, commonly known as a Sea Butterfly, which is actually a type of a snail! They have wings that help them swim through the water and a bright red tail. They also feed on smaller plankton that drifts by them.

This a collection of various fish, planktonic crustaceans and snails that were photographed off Nantucket Shoals.

This this a Bolinopsis, which is another type of Comb Jelly. This one has a different shape than the other Comb Jelly. These are also predators of smaller plankton. They also have rows of tiny hairs on their body that they use to swim slowly through the water.

This is a Chaetognath, commonly know as an Arrow Worm. They are very clear, like glass, which makes them hard to see for their prey or predators that might eat them. They are fierce predators that feed on anything smaller than them. They have sharp spines on their head that they stab their prey with. We have been finding many of these in our bongo nets!

Personal Log

We have been on the NOAA Ship Gordon Gunter now for 8 days. It’s really hard to believe how much I have learned in a little over a week. It’s been a crash course in a whole bunch of cool science, as well as life on ship. It’s been a little crazy with the weather, it has not been very cooperative, especially the wind. Even though the weather has forced us to make changes in our original plans, the scientists have been very flexible and have done what they can to get their jobs done. Today we have come back from Georges Banks and we are going to be passing through the Cape Cod Canal and spending some time in Cape Cod Bay. Luckily there are a lot of Right Whales known to be there. It’s been really fun getting to know all the scientists, NOAA Corps folks and the crew. Everyone is very nice and it’s amazing how quickly I feel like I have known these people for a long time in just over a week. It is nice to be around like-minded folks who also love science. Yesterday was one of the nicest days, it was warm enough that we didn’t have to wear the mustang suits. I was also able to decorate and deploy a drifter buoy, but more on that later!

Me catching the beautiful sunset before the storm came in.

April 10, 2014August 20, 2021

Kimberly Gogan: A Ship Full of Science! April 9, 2014

NOAA Teacher at Sea
Kim Gogan
Aboard NOAA Ship Gordon Gunter
April 7 – May 1, 2014

Mission: AMAPPS & Turtle Abundance Survey, Ecosystem Monitoring
Geographical area of cruise: North Atlantic Ocean
Date: Wednesday, April 9th

Weather Data from the Bridge
Air Temp: 5.5 Degrees Celsius
Wind Speed: 9.0 Knots
Water Temp: 4.6 Degrees Celsius
ater Depth: 41.2 Meters

The Science Teams (Photo Credit to Mark Weekley) — The Science Teams – Photo by Mark Weekly

Science and Technology Log

If Science at Sea is what I wanted, this is the ship for it! The evening of our departure from Newport, R.I. on Monday, April 7th, the group of scientists met in the staff lounge for a meeting of the minds. I soon found out that there was an array of scientist on the ship all with different goals and science they wanted to conduct. On this ship we have two teams of Oceanographers, a day team and a night team. The Oceanographers are generally taking underwater tests and samples using a variety of equipment. We also have the Marine Mammal Observer Team who are on the look out for any sort of mammals that may poke head out of the water such as whales and dolphins.

There is also a group of Birders collecting data on any bird sightings. And lastly we have our Acoustics, or sound team, that is listening for the sounds of marine mammals. I also learned at that meeting that it would take a lot of teamwork and collaboration on the part of each of the Scientist crews, as well as the NOAA Corps and crew to make it all happen.

Every day the representatives from each team have to get together to coordinate the timing of each of the events that will happen throughout the day. The Mammal and Birding Observer teams are on the same schedule and can collect sighting data throughout the day from 7 AM to 7 PM, only stopping for lunch, as they need daylight to conduct their work. The daytime Oceanographers plan their work of collecting samples around the observer teams, sending off their collection equipment before 7AM, at lunch, and then again at 7PM when the observers teams are done. The nighttime Oceanographers are not working during the same time as other scientists so this gives them the opportunity to to do as many test and collections as they can without interrupting anyone else’s work. The Acoustic team can work anytime of day or during any kind of weather without conflicting with anyone as long as the water is deep enough to drop their equipment. It sounds like an easy schedule but there are many things, like weather, technology and location, that could disrupt this carefully orchestrated schedule of science. When that happens, and it has, everyone must be flexible and work together to make sure everyone can conduct the science they need.

Me helping to bring the Bongo net back onto the ship for cleaning. (Photo credit Chris) — Me helping to bring the Bongo net back onto the ship for cleaning. – Photo by Chris Tremblay

Jerry Prezioso tying the bottom of the Bongo nets getting them really to be put in the water. — Scientist Jerry Prezioso tying the bottom of the Bong nets getting them really to be put in the water.

Science Spotlight

Since there is so much science happening on the ship that I am doing every day, I am going to have to share just one thing at a time or I would be writing for hours! Today’s science spotlight is about scientist Jerry Prezioso and the Bongo nets. Jerry is an Oceanographer who works at the NOAA Lab in Narragansett, R.I. Jerry primarily studies plankton distribution. He has been on many trips on NOAA ships since he was 18!

Today Jerry taught me how to do a Bongo net sample that is used to collect plankton from the various water columns. At the top of the net there is a piece of equipment called a CTD (Conductivity Temperature & Depth Unit) that communicates with the computers in the lab on the ship. The scientists in the lab use that piece of equipment to detect how far down the net is going and when it is close to the bottom, as well as collect data on the water temperature and salinity.

Once the CTD is set and turned on, the Bongo net can be lowered into the water. The nets have weights on them to sink them close to the bottom. Once the nets are close a scientist at the computer has the cable operator pull the nets up and out of the water. Once they are on deck they have to be washed down so all the organisms that were caught in the netting go to the cod end of the nets. The cod ends of the nets are opened up and the organisms are rinsed into a sieve where they will carefully be transferred into glass bottles, treated with formaldehyde and sent to a lab for sorting. There were lots of organisms that were caught in the net. Some that we saw today were: Copepods, Comb Jellies or Ctenophora, Herring Larva, aquatic Arrow Worms or Chaetognaths and tons of Phytoplankton and Zooplankton. The Bongo nets are towed several times a day and night to collect samples of plankton.

Jerry Prezioso and I washing down the Bongo Nets. – Photo by Chris Tremblay.

A shot of some of the creatures we caught being filtered into sampling jars for processing.

Personal Log

The start to the trip has been a little rough. It feels like this is the first day we have been able to do anything. Monday we had to sit in port and wait for a scientist to calibrate some equipment before we left so we didn’t get underway until bed time. When we awoke, the weather was bad and the seas were very rough. Several people were very sick and some still are. We were only able to drop one piece of acoustic equipment all day (more on that in another blog). We also had to change the plans on where we were going and move closer to shore due to the weather.

On a ship you need to be very flexible as things are changing all the time! Today was the the first day we were able to do any real science for a sustained amount of time and there were definitely lots of bugs and kinks that needed to be worked out. On top of dropping the BONGO nets with Jerry, I was also able to spend some time and fill in some shifts on the the decks with the Marine Mammal team watching for whales and dolphins. We had a few cool sighting of Humpbacks, Minke, and a Right Whales! (More on them and what they do in another blog too.) On another note, the state rooms are huge and I am sharing a room with one of the acoustic scientists, Genevieve. She is very nice and helpful. The food on the ship is spectacular! I am very surprised how good it is and how many choices there are every meal. All and all things are off to a good start and there is so much more I have to share with everyone about what all these scientist do and it is only our first “real” day!

Did You Know?

Did you know that North Atlantic Right Whales have a V- shaped blow. Their blow holes (two) are separated which gives them the characteristic blow shape.

Check out this link to the website at Northeast Fisheries Science Center’s Protected Species Branch (NEFSC PSB) Right Whale Team and the work we do there. There is an interactive Google map site and wonderful links.

Boarding the NOAA Ship Gordon Gunter in Newport, R.I.

September 16, 2013August 20, 2021

Britta Culbertson: The Beat of the Bongo (Part 2) – Catching Zooplankton, September 12, 2013

NOAA Teacher at Sea
Britta Culbertson
Aboard NOAA Ship Oscar Dyson
September 4-19, 2013

Mission: Juvenile Walley Pollock and Forage Fish Survey
Geographical Area of Cruise: Gulf of Alaska
Date: Wednesday, September 12th, 2013

Weather Data from the Bridge (for Sept 12^th, 2013 at 9:57 PM UTC):
Wind Speed: 23.05 kts
Air Temperature: 11.10 degrees C
Relative Humidity: 93%
Barometric Pressure: 1012.30 mb
Latitude: 58.73 N Longitude: 151.13 W

Science and Technology Log

We have been seeing a lot of humpback whales lately on the cruise. Humpback whales can weigh anywhere from 25-40 tons, are up to 60 feet in length, and consume tiny crustaceans, plankton, and small fish. They can consume up to 3,000 pounds of these tiny creatures per day (Source: NOAA Fisheries). Humpback whales are filter feeders and they filter these small organisms through baleen. Baleen is made out of hard, flexible material and is rooted in the whale’s upper jaw. The baleen is like a comb and allows the whale to filter plankton and small fish out of the water.

Baleen — This whale baleen is used for filter feeding. It’s like a small comb and helps to filter zooplankton out of the water. (Photo credit: NOAA)

I’ve always wondered how whales can eat that much plankton! Three thousand pounds is a lot of plankton. I guess I felt that way because I had never seen plankton in real-life and I didn’t have a concept of how abundant plankton is in the ocean. Now that I’m exposed to zooplankton every day, I’m beginning to get a sense of the diversity and abundance of zooplantkon.

In my last blog entry I explained how we use the bongo nets to capture zooplankton. In this entry, I’ll describe some of the species that we find when clean out the codends of the net. As you will see, there are a wide variety of zooplankton and though the actual abundance of zooplankton will not be measured until later, it is interesting to see how much we capture with nets that have 20 cm and 60 cm mouths and are towed for only 5-10 minutes at each location. Whales have much larger mouths and feed for much longer than 10 minutes a day!

Cleaning the codends is fairly simple; we spray them down with a saltwater hose in the wet lab and dump the contents through a sieve with the same mesh size as the bongo net where the codend was attached. The only time that this proves challenging is if there is a lot of algae, which clogs up the mesh and makes it hard to rinse the sample. Also, the crab larvae that we find tend to hook their little legs into the sieve and resist being washed out. Below are two images of 500 micrometer sieves with zooplankton in them.

Crab larvae (megalopae) that we emptied out of the codend.

Some of the species of zooplankton we are finding include different types of:

Megalopae (crab larvae)
Amphipods
Euphausiid (krill)
Chaetognaths
Pteropods (shelled: Limasina and shell-less: Clione)
Copepods (Calanus spp., Neocalanus spp., and Metridea spp.)
Larval fish
Jellyfish
Ctenophores

The other day we had a sieve full of ctenophores, which are sometimes known as comb jellies because they possess rows of cilia down their sides. The cilia are used to propel the ctenophores through the water. Some ctenophores are bioluminescent. Ctenophores are voracious predators, but lack stinging cells like jellyfish and corals. Instead they possess sticky cells that they use to trap predators (Source: UC Berkeley). Below is a picture of our 500 micrometer sieve full of ctenophores and below that is a close-up photo of a ctenophore.

It’s fun to compare what we find in the bongo nets to the type of organisms we find in the trawl at the same station. We were curious about what some of the fish we were eating, so we dissected two of the Silver Salmon that we had found and in one of them, the stomach contents were entirely crab larvae! In another salmon that we dissected from a later haul, the stomach contents included a whole capelin fish.

Juvenile pollock are indiscriminate zooplanktivores. That means that they will eat anything, but they prefer copepods and euphausiids, which have a high lipid (fat) content. Once the pollock get to be about 100 mm or greater in size, they switch from being zooplanktivores to being piscivorous. Piscivorous means “fish eater.” I was surprised to hear that pollock sometimes eat each other. Older pollock still eat zooplankton, but they are cannibalistic as well. Age one pollock will eat age zero pollock (those that haven’t had a first birthday yet), but the bigger threat to age zero pollock is the 2 year old and older cohorts of pollock. Age zeros will eat small pollock larvae if they can find them. Age zero pollock are also food for adult Pacific Cod and adult Arrowtooth Flounder. Older pollock, Pacific Cod, and Arrowtooth Flounder are the most voracious predators of age 0 pollock. Recently, in the Gulf of Alaska, Arrowtooth Flounder have increased in biomass (amount of biological material) and this has put a lot of pressure on the pollock population. Scientists are not yet sure why the biomass of Arrowtooth Flounder is increasing. (Source: Janet Duffy-Anderson – Chief Scientist aboard the Dyson and Alaska Fisheries Science Center).

The magnified images below, which I found online, are the same or similar to some of the species of zooplankton we have been catching in our bongo nets. Click on the images for more details.

A chaetognath found in the Bering Sea. (Photo credit: Dave Forcucci, NOAA)

A type of euphausiid called Thysanoessa raschii. (Photo credit: WoRMS Database)

Dungeness crab megalopa (larval form). Photo credit: Liz Leavens, Padilla Bay NERR

A type of naked or shell-less pteropod called an “ice snail”. (Photo credit: Kevin Raskoff, NOAA Office of Ocean Exploration)

A type of copepod called Calanus. (Photocredit: Russ Hopcroft, University of Alaska, Fairbanks)

Limacina helicina, a type of shelled pteropod. (Photo credit: Russ Hopcroft, University of Alaska, Fairbanks)

Neocalanus critatus – a type of copepod found in the Gulf of Alaska. (Photocredit: Russ Hopcroft, University of Alaska, Fairbanks)

A type of amphipod found in the cold waters around Alaska. (Photo credit: Russ Hopcroft, NOAA Office of Ocean Exploration)

Metridia pacifica – a type of copepod found the Gulf of Alaska. (Photo credit: Russ Hopcroft, University of Alaska, Fairbanks)

Personal Log (morning of September 14, 2013)

I’m thankful that last night we had calm seas and I was able to get a full eight hours of sleep without feeling like I was going to be thrown from my bed. This morning we are headed toward the Kenai Peninsula, so I’m excited that we might get to see some amazing views of the Alaskan landscape. The weather looks like it will improve and the winds have died down to about 14 knots this morning. Last night’s shift caught an octopus in their trawl net; so hopefully, we will find something more interesting than just kelp and jellyfish in our trawls today.

Did You Know?

I mentioned that we had found some different types of pteropods in our bongo nets. Pteropods are a main food source for North Pacific juvenile salmon and are eaten by many marine organisms from krill to whales. There are two main varieties of pteropods; there are those with shells and those without. Pteropods are sometimes called sea butterflies.

Unfortunately, shelled pteropods are very susceptible to ocean acidification. Scientists conducted an experiment in which they placed shelled pteropods in seawater with pH and carbonate levels that are projected for the year 2100. In the image below, you can see that the shell dissolved slowly after 45 days. If pteropods are at the bottom of the food chain, think of the implications of the loss of pteropods for the organisms that eat them!

Read more about ocean acidification on the NOAA’s Pacific Marine Environmental Laboratory (PMEL) website. Also, check out this press release from November 2012 by the British Antarctic Survey about the first evidence of ocean acidification affecting marine life in the Southern Ocean.

Teacher’s Corner

In my last blog entry on the bongo, I talked about using the “frying pan” or clinometer to measure wire angle. If you’re interested in other applications of clinometers, there are instructions for making homemade clinometers here and there’s also a lesson plan from National Ocean Services Education about geographic positioning and the use of clinometers this website.

If you are interested in teaching your students about different types of plankton, here is a Plankton Wars lesson plan from NOAA and the Southeast Phytoplankton Monitoring Network, which helps students to understand how plankton stay afloat and how surface area plays a role in plankton survival.

If you would like to show your students time series visualizations of phytoplankton and zooplankton, go to NOAA’s COPEPODite website.

Zooplankton time series visualization from the COPEPODite website.

For more plankton visualizations and data, check out NOAA’s National Marine Fisheries Service website.

If you are interested in having your students learn more about ocean acidification, there is a great ocean acidification module developed for the NOAA Ocean Data Education Project on the Data in the Classroom website.

September 13, 2013August 20, 2021

Britta Culbertson: The Beat of the Bongo (Part 1): Catching Zooplankton, September 11, 2013

NOAA Teacher at Sea
Britta Culbertson
Aboard NOAA Ship Oscar Dyson
September 4-19, 2013

Mission: Juvenile Walley Pollock and Forage Fish Survey
Geographical Area of Cruise: Gulf of Alaska
Date: Wednesday, September 11th, 2013

Weather Data from the Bridge (for Sept 11^th, 2013 at 10:57 PM UTC):
Wind Speed: 4.54 kts
Air Temperature: 10.50 degrees C
Relative Humidity: 83%
Barometric Pressure: 1009.60 mb
Latitude: 58.01 N Longitude: 151.18 W

Science and Technology Log

What is a bongo net and why do we use it?

As I mentioned in a previous entry, one of the aspects of this cruise is a zooplankton survey, which happens at the same stations where we trawl for juvenile pollock. The zooplankton are prey for the juvenile pollock. There are many types of zooplankton including those that just float in the water, those that can swim a little bit on their own, and those that are actually the larval or young stage of much larger organisms like crab and shrimp. We are interested in collecting the zooplankton at each station because because we are interested in several aspects of juvenile pollock ecology, including feeding ecology. In order to catch zooplankton, we use a device called a bongo net. The net gets its name because the frame resembles bongo drums.

20bon — Diagram of a 20 cm bongo net set-up. (Photo credit: NOAA – Alaska Fisheries Science Center)

The bongo net design we are using includes 2 small nets on a 20 cm frames with 153 micrometer nets attached to them and 2 large nets on 60 cm frames with 500 micrometer nets. The 500 micrometer nets catch larger zooplankton and the 153 micrometer nets catch smaller zooplankton. In the picture above, there are just two nets, but our device has 4 total nets. At the top of the bongo net setup is a device called the Fastcat, which records information from the tow including the depth that bongo reaches and the salinity, conductivity, and temperature of the water.

Bongo in water — This is what the bongo looks like when it’s finally in the water (Photo credit: John Eiler)

What happens during a bongo net tow?

The process of collecting zooplankton involves many people with a variety of roles. It usually takes three scientists, one survey tech, and a winch operator who will lower the bongo net into the water. In addition, the officers on the bridge need to control the speed and direction of the boat. All crew members are in radio contact with each other to assure that the operation runs smoothly. Two scientists and a survey tech stand on the “hero deck” and work on getting the nets overboard safely. Another scientist works in a data room at a computer which monitors the depth and angle of the bongo as it is lowered into the water. It is important to maintain a 45 degree angle on the wire that tows the bongo to make sure that water is flowing directly into the mouth opening of the net. One of the scientists on the hero deck will use a device that we lovingly call the “frying pan,” but more accurately it is called a clinometer or inclinometer. The flat side of the device gets lined up with the wire and an arrow dangles down on the plate and marks the angle. The scientist calls out the angle every few seconds so that the bridge knows whether or not to increase or decrease the speed of the ship in order to maintain the 45 degree angle necessary.

Peter and the pan — Scientist Peter Proctor holds up the “frying pan” also known as a clinometer or inclinometer, which is used to measure the wire angle of the bongo when it’s in the water.

Meanwhile, back at the computer, we monitor how close the bongo gets to the bottom of the ocean. We already know how deep the ocean is at our location because of the ship’s sonar. The bongo operation involves a bit of simple triangle geometry. We know the depth and we know the angles, so we just have to calculate the hypotenuse of the triangle that will be created when the bongo is pulled through the water to figure out how much wire to let out. The survey tech uses a chart that helps him determine this quickly so he knows what to tell the winch operator in terms of wire to let out. In the images below, you can see what we are watching as the bongo completes its tow. The black line indicates the depth of the bongo, and the red, purple, and blue lines indicate temperature, conductivity, and salinity.

Good bongo tow — This is an example of a good bongo tow. The black line on the left of the graph shows a consistent tow angle both up and down. The key is that the black line should have a “v” shape on the graph if the tow is good.

Bad bongo — This graph shows what happens when a bongo gets caught in the current and stays at the same depth for a while. Look at how the black line isn’t smooth, but levels off for a bit. This happened with the bongo both when it was going down and coming back up to the surface.

When the bongo is within in 10 meters of the bottom, the survey tech radios the winch operator to start bringing the bongo back up. It usually takes longer for it to come up as it does for it to go out, nevertheless, the 45 degree wire angle needs to be maintained. When the survey tech sees the bongo at the surface of the water, the two scientists on the hero deck get ready to grab it. This operation can be quite difficult when it’s windy and the seas are rough. If you look at the sequence of the photos below, pay attention to the horizon line where the water meets the sky and you can get a sense of the size of the swells that day.

Bongo Coming On Board — Chief Scientist Janet Duffy-Anderson and scientist Peter Proctor bringing the bongo back on deck.

Bongo retrieval — Bongo nearly over the railing of the hero deck.

Bongo on deck — Pulling the nets over the railing.

Bongo on board — Finally pulling up the codends of the bongo net. Note the change in the horizon line on all 4 pictures. There were pretty big swells this day.

When the bongo is safely back on deck, the person in the data room records the time of the net deployment, how long it takes to go down and up, how much wire gets let out, and the total depth at the station. If anything goes wrong, this is also noted in the data sheet.

As the bongo reaches the surface, the scientists grab the net keep it from banging into the side of the ship. When the net is on board, the next step is to read the flowmeters on the nets that indicate how much water has flowed through them. Then we rinse the nets and wash all of the material down the nets and into the “codends” at the very end of the net. These are little containers that can be detached and emptied to collect the samples.

Vince, the survey tech, and Peter the scientist prepare to read the flowmeters on the bongo.

Britta and Peter washing the bongo nets.

Once the codends are detached, they are taken to the wet lab and rinsed. Each of the four parts of the net has a codend where the zooplankton are caught. The zooplankton are rinsed out of the codends into a sieve and then collected in a jar and preserved with formalin. The purpose of having two of each of the 20 cm and 60 cm bongo nets is to ensure that if one sample is bad or accidentally dumped, there is always a backup. I have had to use the backup once or twice when there was a big jellyfish in the codend that kept me from getting all of the zooplankton out of the sample.

cleaning the codends and sieve — Britta rinsing the 500 micrometer sieve.

After we collect the zooplankton the samples are shipped to Seattle when we return to port. Back in the labs, the samples are sorted, the zooplankton are identified to species, and the catch is expressed at number per unit area. This gives a quantitative estimate of the density of plankton in the water. A high density of the right types of food means a good feeding spot for the juvenile walleye pollock! This sorting process can take approximately one year. I think it’s pretty amazing how much work goes into collecting the small samples we get at each station. Just to think of all of the person hours and ship hours involved makes me realize how costly it is to study the ocean.

Colleen and zooplankton jar — Scientist Colleen Harpold holding up one of the preserved jars of zooplankton.

Colleen with zooplankton — Scientist Colleen Harpold holding up one of the preserved jars of zooplankton that has A LOT of algae in it too!

Personal Log

It is hard to believe that I’ve been on the ship a week now. It feels strange that just 7 days ago I had never heard of a bongo net or an anchovy net. Now I see them every day and I know how to identify several types of fish, jellyfish, and zooplankton. I love working with the scientists and learning about the surveys we are doing. Nearly every trawl reveals a special, new organism, like the Spiny Lumpsucker – go look that one up, I dare you! We don’t have much down time and I’m trying to blog in between stations, but sometimes the time between stations after we finish our work can be 45 minutes and sometimes just 15 minutes. So we are pretty much on the go for the whole 12-hour shift. That’s where the fortitude part of Teacher at Sea comes in. You definitely need to have fortitude to endure the long hours, occasional seasickness (I like to think of it as “sea discomfort”), and periodic bad weather.

By now though, it all seems routine and I’d like to think I’ve gotten used to being thrown around in my sleep a little now and again when we hit some rough seas. This experience has been so worthwhile and even though I look forward to the comforts of home, I don’t really want it to end. When I graduated from college, I worked with a herpetologist studying lizards in the desert south of Carlsbad, New Mexico. I have fond memories of living in a tent for four months and collecting lizards all day to bring back to camp to measure and check for parasites. I often miss doing scientific work, so Teacher at Sea has given me the opportunity to be a scientist again and to learn about a whole new world in the ocean. What a treat! One of the reasons I chose to be a teacher was to be able to share my excitement about science with students and I feel so lucky that I get to share this experience too.

Did you know?

There are two species of Metridia, a type of copepod (zooplankton), that are found in the Gulf of Alaska/Bering Sea. One of them is called Metridia lucens and the other one is Metridia oketensis. These copepods are bioluminescent, which means that they glow when they are disturbed. They sometimes glow when they are in the wake of the ship or on the crest of a wave. Tonight when I was draining a codend into a sieve, my sieve looked like it had blue sparkles in it, but just for a second! I asked our resident zooplankton expert, Colleen Harpold what they might be and she thought that my blue sparkles likely belonged to the genus Metridia.

If you are interested in reading a little more about Metridia, check out this blog from Scientific American on copepods in the Bering Sea!

This is an image of Metridia longa. (Photo credit: NOAA/Hopcroft)

Glowing Metridia — This is a picture from Scientific American of Metridia spp. glowing while in a sieve. (Photo Credit: Chris Linder, Woods Hole Oceanographic Institute)

Thanks for reading! Please leave me some comments or ask questions about any of the blog posts and feel free to ask other questions about the work we are doing or what it’s like at sea! I would love to be able to answer real-time while I am at sea.

June 19, 2013August 11, 2021

Sue Cullumber: Testing the Water and More, June 19, 2013

NOAA Teacher at Sea
Sue Cullumber
Onboard NOAA Ship Gordon Gunter
June 5–24, 2013

Mission: Ecosystem Monitoring Survey
Date: 6/19/2013
Geographical area of cruise: The continental shelf from north of Cape Hatteras, NC, including Georges Bank and the Gulf of Maine, to the Nova Scotia Shelf

Weather Data from the Bridge:
Latitude/longitude: 3853.256 N, 7356.669W
Temperature: 18.6ºC
Barometer: 1014.67 mb
Speed: 9.7 knots

CTDscreen — CTD reading on the computer. Blue is density, red is salinity, green is temperature and black indicates the depth.

Science and Technology Log:

Even before the plankton samples are brought onboard, scientists start recording many types of data when the equipment is launched. The bongos are fitted with an electronic CTD (conductivity, temperature and density) and as they are lowered into the ocean the temperature, density and salinity (salt content) are recorded on a computer. This helps scientists with habitat modeling and determining the causes for changes in the zooplankton communities. Each bongo net also has a flow-through meter which records how much water is moving through the net during the launch and can is used to estimate the number of plankton found in one cubic meter of water.

ZIplankton — Zooplankton (Z) and Icthyoplankton (I) samples.

The plankton collected from the two bongo nets are separated into two main samples that will be tested for zooplankton and icthyoplankton (fish larvae and eggs). These get stored in a glass jars with either ethanol or formalin to preserve them. The formalin samples are sent to a lab in Poland for counting and identification. Formalin is good for preserving the shape of the organism, makes for easy identification, and is not flammable, so it can be sent abroad. However, formalin destroys the genetics (DNA) of the organisms, which is why ethanol is used with some of the samples and these are tested at the NOAA lab in Narragansett, Rhode Island.

sueplankton — Holding one of our zooplankton samples – photo by Paula Rychtar.

When the samples are returned from Poland, the icthyoplankton samples are used by scientists to determine changes in the abundance of the different fish species. Whereas, the zooplankton samples are often used in studies on climate change. Scientists have found from current and historic research (over a span of about 40 years) that there are changes in the distribution of different species and increases in temperature of the ocean water.

At the Rosette stations we take nutrient samples from the different water depths. They are testing for nitrates, phosphates and silicates. Nutrient samples are an important indicator of zooplankton productivity. These nutrients get used up quickly near the surface by phytoplankton during the process of photosynthesis (remember phytoplankton are at the base of the food chain and are producers). As the nutrients pass through the food chain (zooplankton eating phytoplankton and then on up the chain) they are returned to the deeper areas by the oxidation of the sinking organic matter. Therefore, as you go deeper into the ocean these nutrients tend to build up. The Rosettes also have a CTD attached to record conductivity, temperature and density at the different depths.

Chris-DICtests — Scientist, Chris Taylor, completing the dissolved inorganic carbon test.

CO2test — The dissolved inorganic carbon test uses chemicals to stop any further biological processes and suspend the CO2 in “time”.

Another test that is conducted on the Rosettes is for the amount of dissolved inorganic carbon. This test is an indicator of the amount of carbon dioxide that the ocean uptakes from outside sources (such as cars, factories or other man-made sources). Scientists want to know how atmospheric carbon is affecting ocean chemistry and marine ecosystems and changing the PH (acids and bases) of the ocean water. One thing they are interested in is how this may be affecting the formation of calcium in marine organisms such as clams, oysters, and coral.

New word: oxidation – the chemical combination of a substance with oxygen.

Personal Log:

This week we headed back south and went through the Cape Cod canal outside of Plymouth, Massachusetts. I had to get up a little earlier to see it, but it was well worth it. The area is beautiful and there were many small boats and people enjoying the great weather.

We also did a small boat transfer to bring five new people onboard, while three others left at the same time. It was hard to say goodbye, but it will be nice to get to know all the new faces.

dolphinsthree — Common Dolphins swimming next to the Gordon Gunter.

So now that we are heading south the weather is warming up. I have been told that we may start seeing Loggerhead turtles as the waters warm up – that would be so cool. We had a visit by another group of Common Dolphins the other day. They were swimming along the side of the ship and then went up to the bow. They are just so fun to watch and photograph.

We have been seeing a lot of balloons (mylar and rubber) on the ocean surface. These are released into the air by people, often on cruise ships, and then land on the surface. Sea turtles, dolphins, whales and sea birds often mistake these for jelly fish and eat them. They can choke on the balloons or get tangled in the string, frequently leading to death. Today, we actually saw more balloons than sea birds!!! A good rule is to never release balloons into the air no matter where you live!

Did you know? A humpback whale will eat about 5000 pounds of krill in a day. While a blue whale eats about 8000 pounds of krill daily.

Question of the day? If 1000 krill = 2 pounds, then together how many krill does a humpback and blue whale consume on a daily basis.

August 8, 2012August 11, 2021

Bhavna Rawal: Net Tow, Dive, Buoy Maintenance and Data Collection, August 8, 2012

NOAA Teacher at sea
Bhavna Rawal
On Board the R/V Walton Smith
Aug 6 – 10, 2012

Mission: Bimonthly Regional Survey, South Florida
Geographic area: Gulf of Mexico
Date: August 8, 2012

.
Weather Data from the Bridge:
Station: 21.5
Time: 1.43 GMT
Longitude: 21 23 933
Latitude: 24 29 057
Wind direction: East of South east
Wind speed: 18 knots
Sea wave height: 2-3 ft
Clouds: partial

Science and Technology Log:

Yesterday, I learned about the CTD and the vast ocean life. Today I learned about a new testing called net tow, and how it is necessary to do, and how it is done.

What is Net Tow? The scientist team in the ship uses a net to collect sargassum (a type of sea weed) which is towed alongside the ship at the surface of the predetermined station.

How did we perform the task? We dropped the net which is made of nylon mess, 335 microns which collects zooplanktons in the ocean. We left this net in the ocean for 30 minutes to float on the surface of the ocean and collects samples. During this time the ship drives in large circles. After 30 minutes, we (the science team) took the net out of the ocean. We separated sargassum species, sea weeds and other animals from the net. We washed them with water, then classified and measured the volume of it by water displacement. Once we measure the volume, we threw them back into the ocean.

Dropped the net which collects zooplanktons in the ocean

Measured the volume of it by water displacement

Types of Sargassum and Plankton: There are two types of sargassum; ones that float, and the other ones that attach themselves to the bottom of the ocean. There are two types of floating sargassum and many types attached to bottom of the ocean.

Also there are two types of plankton; Zooplankton and phytoplankton. As you all know phytoplankton are single celled organisms, or plants that make their own food (photosynthesis). They are the main pillar of the food chain. It can be collected in a coastal area where there is shallow and cloudy water along the coastal side. The phytoplankton net is small compared to the zooplankton and is about 64 microns (small mess).

Zooplanktons are more complex than phytoplankton, one level higher in their food chain. They are larva, fish, crabs etc. they eat the phytoplankton. The net that is made to catch zooplankton, is about 335 microns. Today, we used the net to collect zooplankton.

Why Net Tow is necessary: Net tow provides information about habitats because tons of animals live in the sargassum. It is a free floating ecosystem. Scientists are interested in the abundance of sargassum and the different kinds of animals, such as larva, fishes, crabs, etc. Many scientists are interested in the zooplankton community structures too.

Dive, Buoy and other data collection equipments: Two science team members prepared for diving; which means that they wore scuba masks, oxygen tanks and other equipment. They took a little boat out from the ship and went to the buoy station. They took the whole buoyancy and other data collection instruments with them. The two instruments were the Acoustic Doppler (ADCP) and the micro cat which was attached to the buoy. The micro cat measures salinity and temperature on profile of currents, and the ADCP measures currents of the ocean. Both instruments collect many data over the period. The reason for bringing them back, is to recover data in a Miami lab and the maintenance of the buoy.

The micro cat measures salinity and temperature on profile of currents

Acoustic Doppler (ADCP) measures currents of the ocean

Personal Log:

My first day on the ship was very exciting and nerve-racking at the same time. I had to take medicine to prevent me from being seasick. This medicine made me drowsy, which helped me to go to sleep throughout the night. The small bunk bed and the noise from the moving ship did not matter to me. I woke up in the morning, and got ready with my favorite ‘I love science’ t-shirt on. I took breakfast and immediately went to meet with my science team to help them out for the CTD and net tow stations. Today, I felt like a pro compared to yesterday. It was a bit confusing during the first day, but it was very easy today.

I started helping lowering the CTD in the ocean. Now I know when to use the lines for the CTD, water sampling for different kinds of testing, how to net tow and do the sargassum classification. I even know how to record the data.

When we have a station call from the bridge, then we work as a team and perform our daily CTD, water testing or net tow. But during the free time, we play card games and talk. Today was fun and definitely action packed. Two science team members dove into the ocean and brought the buoy back. I also saw a fire drill.

Nelson (the chief scientist) took me to see TGF or called the flow through station which is attached inside the bottom of the ship. This instrument measures temperature, salinity, chlorophyll, CDOM etc. Nelson explained the importance of this machine. I was very surprised by the precise measurements of this machine. Several hours later, I went to the captain’s chamber, also called the bridge. I learned how to steer the boat, and I was very excited and more than happy to sit on the captain’s chair and steer.

aug 8 048 — Excited to sit on the captain’s chair and steer the R/V Walton Smith

We have also seen groups of dolphins chasing our ship and making a show for us. We also saw flying fishes. In the evening, around 8 o’clock after dinner, I saw the beautiful colorful sunset from the ship. I took many videos and pictures and I can’t wait to process it and see my pictures.

aug 8 044 — Saw groups of dolphins ahead of ship

Around 10 o’clock in the night, it was net tow time again. We caught about 65 moon jelly fishes in the net and measured their volumes. Nelson also deployed a drifter in the ocean.

aug 6 104 — See moon jelly fish in my hand

Today was very fun and a great learning opportunity for me, and don’t forget the dolphins, they really made my day too!

Question of the Day:
How do you measure volume of solid (sea grass)?

New Word:
Sargassum

Something to Think About:
Why scientists use different instruments such as CTD as well as TFG to measuretemperature, salinity, chlorophyll, CDOM etc?

Challenge Yourself:
Why abundance of sargassum, types of animals and data collection is important in ocean?

Did you Know?
The two instruments were the Acoustic Doppler (ADCP) and the micro cat which was attached to the buoy. The micro cat measures salinity and temperature on profile of currents, which means it measures at surface of the ocean, middle of the ocean and bottom layer of the ocean too.

Animals Seen Today:
Five groups of dolphins
Seven flying fishes
Sixty five big moon jelly fishes
Two big crabs

June 21, 2012August 11, 2021

Valerie Bogan: The Adventure Continues: June 12, 2012

NOAA Teacher at Sea
Valerie Bogan
Aboard NOAA ship Oregon II
June 7 – 20, 2012

Mission: Southeast Fisheries Science Center Summer Groundfish (SEAMAP) Survey
Geographical area of cruise: Gulf of Mexico
Date: Tuesday June 12, 2012

Weather Data from the Bridge:
Sea temperature 28 degrees celsius, Air temperature 26.4 degrees celsius, building seas.

Science and Technology Log

Today I want to discuss the neuston net. This is a very large net made out of finely woven mesh which is deployed (shoved off the side of the boat) in order to catch plankton. There are three types of plankton: phytoplankton (plants and algae), zooplankton (animals), and ichytoplankton (baby fish). The neuston net rides along the surface of the water for ten minutes scooping up any organisms which are near the surface. After the ten minutes are up, the deck crew uses a crane to pull the net out of the water and bring it up to the point where someone can wash it down with a hose. This is necessary because not all of the plankton ends up in the cod end (the place where the collection jar is located) so we have to use a hose to get all of the loose stuff washed into the end of the net. After the net is washed down, the cod end is carefully removed, placed in a bucket and taken to the stern (back) of the ship where it is processed.

Putting out the neuston net — This is how the neuston net is moved from the ship into the water. From left to right Jeff, Marshall, and Chris are safely deploying the net.

To process the sample you must first empty the contents of the cod end into a filter which will allow the water to run out but will keep the sample. Then you transfer (move) the sample from the filter into a glass sample jar. Sometimes the sample smoothly slides into the jar and other times you have to wash down the filter with some ethanol. Once all of the sample is in the jar it is topped off with ethanol, a tag is placed inside the jar, and another tag is put on top of the jar. This sample is stored on the boat and taken back to the NOAA lab where it will be cataloged.

Processing the neuston sample — In this picture I am filtering out the water from the neuston sample so it can be placed in a sample jar.(Picture by Francis)

Personal Log

Today is our fifth day at sea and I’m feeling fairly comfortable with my duties on the ship. I was assigned to the night watch which runs from midnight till noon the next day. I’ll admit I didn’t make it the entire time the first day. We got done early and despite my intentions to stay up until my shift, I would have ended I falling asleep. The second night was better. I was beyond exhausted at the end, but I did manage to make it through the entire shift. At this point my mind and body have adjusted to the shift and I can easily drift to sleep at 3 pm and get up at 11:15 pm. Students, this is a great example of what it means to be responsible. If I was given the choice, do you think I would have chosen these crazy hours or to work twelve hours straight? No of course not but I really wanted to come on this expedition and this work assignment is part of the trip. So I’m doing the same thing I would expect you to do in a situation like this: accept it and get the work done.

Now I don’t want you to think that the trip is just about hard work. It’s also about seeing new places and getting to know some interesting people. I started out this trip in Pascagoula Mississippi, a city and state I never planned on visiting before this assignment. However, the people there were so helpful and friendly that I would gladly go back to see more of this region. All of you from the Kokomo area know that the major employers are automobile companies. Well, Pascagoula also has a major industry: ship building. So despite the distance between Kokomo and Pascagoula–about 900 miles–each town depends on an industry for their survival and both towns are incredibly proud of their contribution to society.

Ship yards in Pascagoula — The major industry in Pascagoula is ship building.

I have been introducing you to parts of the ship, and today I’m going to tell you about the bridge. Now this is not the type of bridge that crosses a river, but rather the command center of the ship. The crew on the bridge is responsible for the safety of all personal on board and for the ship itself. There is a vast array of technology on the bridge which the crew uses to plot our course, check the weather, and to do hundreds of other things which are necessary for the ship to function.

June 20, 2012August 11, 2021

Alexandra Keenan: A Whale of an Adventure Begins! June 16, 2012

NOAA Teacher at Sea
Alexandra Keenan
(Almost) Onboard NOAA Ship Henry B. Bigelow
June 18 – June 29

Mission: Cetacean biology
Geographical Area of Cruise: Gulf of Maine
Date: June 16, 2012

Personal Log

Saludos! My name is Alexandra Keenan, and I teach Astronomy and Physics at Rio Grande City High School. Rio Grande City is a rural town located at the arid edge of the Rio Grande Valley. Because of our unique position on the Texas-Mexico border, our community is characterized by a rich melding of language and culture. Life in a border town is not always easy, but my talented and dedicated colleagues at RGC High School passionately advocate for our students, and our outstanding students gracefully rise to and surmount the many challenges presented to them.

Che's — Me in downtown Rio Grande City. Our historic buildings are evocative of the old “Wild West.”