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: 57o 34.6915’
Longitude: 150o 06.9789’
Wind: 18 knots, South
Seas: 4-6 feet
Air Temperature: 46oF (8oC)
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).

 

 

Phronima

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.”

 

 

 

 

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: 59o 39.0964’ N
Longitude: 146o05.9254’ W
Wind: Southeast, 15 knots
Air Temperature: 10oC (49oF)
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.

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

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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?”

Euphausiids

Euphausiids (also known as krill) are among the types of zooplankton we collected with the bongo nets last night.

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.

WWII shipwreck

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 1/8th 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 6th 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!

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

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.

A cod end

A cod end

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

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.

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

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

IMG_1101

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.

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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.

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

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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.

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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!

 

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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.

 

sea angel

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.”

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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!

diatoms

Diatoms as seen through a microscope.

 

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.”

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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:

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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.

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

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The CTD

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.

IMG_3032

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)

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