Tag: phytoplankton

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Catherine Fuller: Into the Copper River Plume, July 7, 2019

NOAA Teacher at Sea

Catherine Fuller

Aboard R/V Sikuliaq

June 28 – July 18, 2019

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

Geographic Area of Cruise: Northern Gulf of Alaska

Date: July 7, 2019

Weather Data from the Bridge

Latitude: 59° 40.065 N
Longitude: 146° 04.523 W
Wave Height: 2-3 ft
Wind Speed: 10.4 knots
Wind Direction: 254 degrees
Visibility:  100 m
Air Temperature: 12.0 °C
Barometric Pressure: 1015.4 mb
Sky: Overcast, foggy


Science and Technology Log

Usually LTER cruises are more focused on monitoring the ecosystem, but in our case, the cruise will also focus on a process study of the Copper River plume.

Copper River plume
This is a satellite photo of the plume with an overlay of the salinity of the water along our course. The darker colors represent the lowest salinity.

This seasonal plume brings iron and fresh water into the marine ecosystem, where they are dispersed by weather and currents. Because our winds have been very light, the plume is retaining its coiled shape remarkably well.  Our sampling on the Middleton Line (prior to the plume study) will add information about how both the Copper River fresh water and iron are spread along the shelf and throughout the food web.  

Clay Mazur
Clay checking the fluorescence of a sample.

Clay Mazur has a particular interest in the iron-rich waters of the plume.  He is a graduate student from Western Washington University who is working under Dr. Suzanne Strom (also onboard). He is one of a few on board who are working on their own experiments as opposed to assisting others.  The overall goal of his work is to study how iron in phytoplankton is limited and how the sporadic addition of it can stimulate growth.  He has a gigantic on-deck incubation experiment in which he will take an iron-limited plankton community from offshore in the Gulf and introduce iron-rich water from the Copper River plume to see what happens.  Clay will measure chlorophyll – an indication of biomass – by which he can estimate the plankton population.  He will also be checking the physiology of plankton in different size classes, and taking samples to see the pigments that every cell produces and if they change over time with the addition of water from the Copper River plume. His hypothesis is that everything should change: phytoplankton species composition, cell size, photosynthetic ‘health’, and chlorophyll production. When phytoplankton are iron-limited, they cannot produce healthy photosynthetic structures. 

Clay measured the same indicators on every station of the MID (Middleton Island) line and will also measure the same on GAK line.  These samples will use the metrics described above to show environmental heterogeneity along the cross-shelf sampling lines. Samples from the MID and GAK line will also allow his iron experiment to be seen in context.  Does the iron-rich community that develops during the experiment match anything that we see on the shelf? How realistic is experiment within the Gulf of Alaska? Clay would also expect a diatom bloom with the introduction of iron into his sample population, but he says there are not a lot of cells greater than 20 microns out here and 5 days may not be enough for diatoms to grow up from this small seed population.

The Acrobat

One specialized instrument being deployed to gather information about the Copper River plume is the Acrobat.  Where the CTD is critical to give a site-specific profile of various indicators in the water column, the Acrobat can provide much of the same information along the path of the research ship, such as through the plume or across the shelf from deep regions to shallow.

CTD Screen
This is an example of the readout that comes from the CTD when it is deployed.

Lead scientist Dr. Seth Danielson from UAF, and Pete Shipton, a mooring technician from UAF’s Seward Marine Center are using the Acrobat to record a number of parameters as it moves through the water column.  The Acrobat is lowered off the stern of the ship and towed behind us.

Acrobat on deck
Bern, the Marine Tech, and Paul, the Bosun, with the Acrobat on deck prior to launch

As it is towed, it dives and climbs in a repeated vertical zigzag pattern to sample the water column vertically along the length of our course, creating a “cross-section” of the ocean along our line.  The Acrobat measures water temperature, salinity, density, chlorophyll, particle concentrations and CDOM (colored dissolved organic matter). The CDOM indicator allows the Acrobat to distinguish between different water colorations.

The path of the Acrobat can be constrained by distance from the surface or seafloor, in which case it receives depth sounder readings from the ship itself to inform its “flight” behavior.  It can also be set to run a path of a set distance vertically, for example, within a 20m variation in depth.  When set to a maximum depth of 40 m, it can be towed at 7-8 kts, but someone must always be monitoring the “flight” of the Acrobat in relation to ship speed to ensure the best possible results. The operator provides a watchful eye for shallow regions and keeps an eye on the incoming data feed.  The Acrobat also has two sets of wings.  The larger set will allow the Acrobat to reach a maximum depth of 100m or carry a larger sensor payload.  The profile being created as we tow through strands of the plume indicates that there is a pronounced layer of fresh water at the surface.  A concentration of phytoplankton, indicated by high chlorophyll a fluorescence levels, lies just beneath the fresh water layer and as we exit the plume, we observe a subtle shift towards the surface.  The fresh water also contains a good deal of sediment from the river that settles to the bottom as the plume spreads out. As we cross through the plume, we see the sediment levels at the surface drop, while the temperature, salinity and density remain fairly constant, showing a continued flow of fresh water at the surface. 

The readout from the Acrobat appears as a series of bar graphs that record in real time and provide a clear picture of what’s happening in the water column as we move.

Acrobat screen
This is what the Acrobat readout looked like as we went through a portion of the plume.

Once the data from the Acrobat is gathered, Dr. Danielson is able to create three-dimensional representations of the water column along our path according to the individual indicators. One that is particularly interesting and important for the Gulf of Alaska is salinity, which exerts strong control on water column stratification and therefore the supply of nutrients into the ecosystem.

Acrobat salinity graph
Here is a 3-D representation of the salinity along our plume route.

The low-salinity waters of the Gulf of Alaska are influenced by the fresh water precipitation, snow melt and glacier melt in the coastal Alaska watershed, including the big rivers like the Copper River and the thousands of un-gauged small streams.  Some of the fresh water runoff eventually flows into the Bering Sea, the Arctic and the Atlantic Ocean, playing its role in the global hydrological cycle and the conveyor belt that circulates water through the world’s oceans.  Oceanographic monitoring has shown that the Gulf of Alaska water column is warming throughout and getting fresher at the surface, a consequence in part of glaciers melting along the rim of the Gulf of Alaska.


Personal Log

Finding my way around onboard was initially somewhat confusing.  I would exit the main lab and turn the wrong way to locate the stairway back up to my room, and it took a few days to figure it out.  Here’s an idea of the path I take in the mornings to get from my room to the lab:

Here’s what our stateroom looks like…yes, it’s kind of messy!

  • Stateroom
    Stateroom
  • Door
    Door exiting stateroom

One rule when you open a door, because the hallways are narrow and the doors are heavy, is to open slowly and check for people.

  • Door
    Door exiting stateroom
  • Hall
    Hallway

The stairs are steep with narrow treads and necessitate careful and constant use of the handrails.

  • Stairs
    Stairs
  • Exit
    Exit

From the main hall, I usually go into the wet lab.

  • Main hall
    Main hall
  • Wet lab
    Wet lab

From the wet lab I can either go into the main lab…

Main lab
Main lab

… or into the Baltic Room.

Baltic Room
Baltic Room

There are six levels to the ship.  At the bottom are supply rooms, equipment, the engine room, workrooms and the gym.  On the main floor are the labs, workrooms, laundry areas and computer center.  On the first floor are science team quarters, a control room for the main deck winches, the mess hall and a lounge.  On the second floor are crew quarters.  The third floor has officer quarters, and the fourth level is the bridge.  There are also observation decks at the stern and bow on the third level.

I have a bit of a reprieve during the plume study, since Steffi’s project does not focus on these waters.  It’s been a great opportunity to shadow other teams and learn about what they’re doing, as well as to explore more of the ship. Now that the first phase of the plume study is over, we are extending it farther out in the gulf to be able to examine a fresh water eddy that is showing up on satellite imagery.  After that, we will have about a 12-hour transit to the next line of stations, called the GAK (Seward) line, where Steffi (and I) will resume her testing. 


Did You Know?

It’s still foggy and the sea state is very calm compared to what everyone expected.  It’s great for the experiments, but doesn’t help with wildlife sightings.  We’re under the influence of a high pressure system currently, which is expected to keep things quiet at least through Wednesday.  At some point next week, we may have a low-pressure system pass through, which would increase wind speed and wave height. 


What Do You Want Kids to Learn from Your Research?

**Note: I’m asking the various scientists on board the same question.  Clay took five days to formulate this and it really captures the essence of his passion for his research and the effects of climate change.  It’s worth the read!

Clay: Recently, I was asked by Cat, our Teacher at Sea for this cruise, what I want members of the general public to take away from my work studying iron limitation of phytoplankton. Though I can provide her a superficial answer to my research question immediately, the motivations for my work go much deeper than answering “How does a micronutrient affect phytoplankton growth?”

There are two main levels at which I want to answer Cat’s question:

1. Proximal: Though phytoplankton are microscopic, they have macroscopic impacts.

2. Philosophical: Why bother in the quest for such knowledge?

Level 1: The Macroscopic Impacts of a Microscopic Organism 

Both human societies and phytoplankton communities are impacted by global climate change. Globally, humans are realizing the need to combat carbon emissions and mediate the effects of increasing global temperatures. Consequences of global climate change for us include mass emigration as sea levels rise and increased frequency of extreme weather events (e.g. droughts, wildfires). As a result, humans are racing to bridge political divides between countries, develop sustainable energy, and manage natural disaster response.

Phytoplankton, too, must respond to global climate change. As sea surface temperatures rise, phytoplankton will have to adapt. CO2 that is dissolved in seawater removes the precious materials some diatoms use to make their “shells” and takes away their protection. Dissolved CO2 can also alter the ability of micrograzers to swim and find food!

Melting glaciers are a double-edged sword. Glacial flour in freshwater runoff brings in vital nutrients (including iron) through the Copper River Plume and phytoplankton love their iron! But freshwater also works to trap phytoplankton in the surface layers. When all the nutrients are used up and you’re a phytoplankton baking in the heat of the sun, being trapped at the surface is super stressful!

As global climate change accelerates in the polar regions, phytoplankton in the Northern Gulf of Alaska are in an evolutionary race against time to develop traits that make them resilient to their ever-changing environment. Phytoplankton crossing the finish line of this race is imperative for us humans, since phytoplankton help to mediate climate change by soaking up atmospheric CO2 during photosynthesis to produce ~ 50 % of the oxygen we breathe!

Phytoplankton also form the base of a complex oceanic food web. The fresh salmon in the fish markets of Pike’s Place (Seattle, WA), the gigantic gulp of a humpback whale in Prince William Sound (AK) and even entire colonies of kittiwakes on Middleton Island (AK) are dependent on large numbers of phytoplankton. When phytoplankton are iron limited, they cannot grow or multiply (via mitosis). In a process called bottom up regulation, the absence of phytoplankton reduces the growth of animals who eat phytoplankton, the animals who eat those animals, and so on up the entire food chain.

Let us consider “The Blob”, an area of elevated sea surface temperature in 2015 to illustrate this point. “The Blob” limited phytoplankton growth and that of herbivorous fishes. As a result, the population of kittiwakes on Middleton Island crashed as the birds could not find enough fish to provide them the nutrients and energy to reproduce successfully. In this way, the kittiwake deaths were directly attributed to a lack of phytoplankton production.

Not only are phytoplankton ecologically important, they are commercially important. For consumers who love to fish (and for the huge commercial fisheries in the Northern Gulf of Alaska), the base of the food web should be of particular interest, as it is the harbinger of change. Fisheries managers currently use models of phytoplankton growth to monitor fish stocks and establish fisheries quotas. If sporadic input of iron from dust storms, glacial runoff, or upwelling stimulate phytoplankton to grow, fish stocks may also increase with the newfound food source. Because phytoplankton are inextricably linked to fish, whales, and seabirds, in years where nutrients are plentiful, you may well see more fish on kitchen tables across the U.S. and Native Alaskans may be able to harvest more seabird eggs.  

Level 2: The Nature of Science

As a supporter of place-based and experiential learning, I view myself as a student with a duel scientist-educator role. To succeed in these roles, I have to be able to combine reasoning with communication and explore questions like “How does science relate to society?” and “How do we foster scientific literacy?” What better way to think about these questions than embarking on a three-week cruise to the Pacific Subarctic?! Not only am I working with amazing Principal Investigators in an immersive research experience, I am able to collect data and think of creative ways to communicate my findings. These data can be used to build educational curricula (e.g. Project Eddy modules, R shiny apps, etc.) in an effort to merge the classroom with the Baltic room (where the CTD is deployed). But what’s the point of collecting data and sharing it?

Science is “a collaborative enterprise, spanning the generations” (Bill Nye) and is “the best tool ever devised for understanding how our world works” (Richard Dawkins). The goal of communicating my results in a way that touches the lives of students is two-fold. One aim is to allow them to appreciate the philosophy of science – that it is iterative, self-correcting, and built upon measurable phenomena. It is the best way that we “know” something.

The other aim is to allow students to engage in scientific discourse and build quantitative reasoning skills. As the renowned astrophysicist Neil DeGrasse Tyson has said, “When you’re scientifically literate the world looks very different to you and that understanding empowers you.” Using phytoplankton to model the scientific process allows students to enter into the scientific enterprise in low-stakes experiments, to question how human actions influence ecosystems, and to realize the role science plays in society. Ultimately, I want students to use my data to learn the scientific process and build confidence to face the claims espoused by the U.S. government and seen on Facebook with a healthy amount of skepticism and an innate curiosity to search for the truth.

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Katie Gavenus: Don’t Forget the Phytoplankton! May 5, 2019

niskin bottles on the rosette

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

Phytoplankton!  These organisms are amazing.  Like terrestrial plants, they utilize energy from the sun to photosynthesize, transforming water and carbon dioxide into sugars and oxygen.  Transforming this UV energy into sugars allows photosynthetic organisms to grow and reproduce, then as they are consumed, the energy is transferred through the food web.  With a few fascinating exceptions (like chemotrophs that synthesize sugars from chemicals!), photosynthetic organisms form the basis of all food webs. The ecosystems we are most familiar with, and depend upon culturally, socially, and economically, would not exist without photosynthetic organisms.

Indeed, productivity and health of species like fish, birds, and marine mammals are highly dependent upon the productivity and distribution of phytoplankton in the Gulf of Alaska. Phytoplankton also play an important role in carbon fixation and the cycling of nutrients in the Gulf of Alaska.  For the LTER, developing a better understanding of what drives patterns of phytoplankton productivity is important to understanding how the ecosystem might change in the future.  Understanding the basis of the food web can also can inform management decisions, such as regulation of fisheries.

niskin bottles on the rosette
Seawater captured at different depths by niskin bottles on the rosette transferred to bottles by different scientists for analysis.

To better understand these patterns, researchers aboard R/V Tiglax use the rosette on the CTD to collect water at different depths.  The plankton living in this water is processed in a multitude of ways.  First, in the lab on the ship, some of the water is passed through two filters to catch phytoplankton of differing sizes.  These filters are chemically extracted for 24 hours before being analyzed using a fluorometer, which measures the fluorescence of the pigment Chlorophyll-a.  This provides a quantitative measurement of Chlorophyll-a biomass. It also allows researchers to determine whether the phytoplankton community at a given time and place is dominated by ‘large’ phytoplankton (greater than 20 microns, predominantly large diatoms) or ‘small’ phytoplankton (less than 20 microns, predominantly dinoflagellates, flagellates, cryptophyte algae, and cyanobacteria).

Preparing filters
Preparing filters to separate large and small phytoplankton from the seawater samples.

For example, waters in Prince William Sound earlier in the week had a lot of large phytoplankton, while waters more offshore on the Seward Line were dominated by smaller phytoplankton.  This has important ramifications for trophic interactions, since many different consumers prefer to eat the larger phytoplankton.  Larger phytoplankton also tends to sink faster than small plankton when it dies, which can increase the amount of food reaching benthic organisms and increase the amount of carbon that is sequestered in ocean sediments.

The Chlorophyll-a biomass measurements from the fluorometer are a helpful first step to understanding the biomass of phytoplankton at stations in the Gulf of Alaska.  However, research here and elsewhere has shown that the amount of carbon fixed by phytoplankton can vary independently of the Chlorophyll-a biomass.  For example, data from 2018 in the Gulf of Alaska show similar primary productivity (the amount of carbon fixed by phytoplankton per day) in the spring, summer, and fall seasons even though the Chlorophyll-a biomass is much higher in the spring.  This is likely because of at least two overlapping factors.  Vertical mixing in the winter and spring, driven primarily by storms, brings more nutrients and iron into the upper water column. This higher nutrient and iron availability in the spring allow for the growth of larger phytoplankton that can hold more chlorophyll.  This vertical mixing also means that phytoplankton tend to get mixed to greater depths in the water column, where less light is available.  To make up for this light limitation, the phytoplankton produce more chlorophyll in the spring so they can more effectively utilize the light that is available.  This variation in chlorophyll over the seasons probably helps to make the phytoplankton community overall more productive, but it makes it problematic to use Chlorophyll-a biomass (which is relatively easy to measure) as a proxy for primary productivity (which is much more challenging to measure).

Phytoplankton sample in the flourometer
A sample of filtered, extracted phytoplankton is placed into the fluorometer.

To address the question of primary productivity more directly, researchers are running an experiment on the ship.  Seawater containing phytoplankton from different depths is incubated for 24 hours.  The container for each depth is screened to let in sunlight equivalent to what the plankton would be exposed to at the depth they were collected from.  Inorganic carbon rich in C13 isotope is added to each container as it incubates. After 24 hours, they filter the water and measure the amount of C13 the phytoplankton have taken up.  Because C13 is rare in ecosystems, this serves as a measurement of the carbon fixation rate – which can then be converted into primary productivity.

Phytoplankton samples from the rosette are also preserved for later analysis in various labs onshore.  Some of the samples will be processed using High Performance Light Chromotography, which produces a pigment profile.  These pigments are not limited to Chlorophyll-a, but also include other types of Chlorophyll, Fucoxanthin (a brownish pigment found commonly in diatoms as well as other phytoplankton), Peridinin (only found in photosynthetic dinoflagellates), and Diadinoxanthin (a photoprotective pigment that absorbs sunlight and dissipates it as heat to protect the phytoplankton from excessive exposure to sunlight).  The pigment profiles recorded by HPLC can be used to determine which species of plankton are present, as well as a rough estimate of their relative abundance.

A different lab will also analyze the samples using molecular analysis of ribosomal RNA.  There are ID sequences that can be used to identify which species of phytoplankton are present in the sample, and also get a rough relative abundance.  Other phytoplankton samples are preserved for microscopy work to identify the species present.  Microscopy with blue light can also be used to investigate which species are mixotrophic – a fascinating adaptation I’ll discuss in my next blog post!

It is a lot of work, but all of these various facets of the phytoplankton research come together with analysis of nutrients, iron, oxygen, dissolved inorganic carbon, temperature, and salinity to answer the question “What regulates the patterns of primary productivity in the Gulf of Alaska?”

There are already many answers to this question.  There is an obvious seasonal cycle due to light availability.  The broad pattern is driven by the amount of daylight, but on shorter time-scales it is also affected by cloud cover.  As already mentioned, vigorous vertical mixing also limits the practical light availability for phytoplankton that get mixed to greater depths.  There is also an overall, declining gradient in primary productivity moving from the coast to the deep ocean. This gradient is probably driven most by iron limitation.  Phytoplankton need iron to produce chlorophyll, and iron is much less common as you move into offshore waters.  There are also finer-scale spatial variations and patchiness, which are partly driven by interacting currents and bathymetry (ocean-bottom geography). As currents interact with each other and features of the bathymetry, upwelling and eddies can occur, affecting such things as nutrient availability, salinity, water temperature, and intensity of mixing in the water column.

View of horizon from station GAK
The early-morning view from station GAK on the ‘Seward Line.’ Patterns of primary productivity are driven both by amount of cloud cover and amount of daylight. During our two weeks at sea, we actually sampled at GAK1 3 separate times. The amount of daylight (time between sunrise and sunset each day) at this location increased by nearly 60 minutes over the two week cruise!

The current work seeks to clarify which of these factors are the most dominant drivers of the patterns in the Gulf of Alaska and how these factors interact with each other. The research also helps to determine relationships between things that can be more easily measured, such as remote-sensing of chlorophyll, and the types of data that are particularly important to the LTER in a changing climate but are difficult to measure across broad spatial scales and time scales, such as primary productivity or phytoplankton size community. Phytoplankton are often invisible to the naked eye.  It would be easy to overlook them, but in many ways, phytoplankton are responsible for making the Gulf of Alaska what it is today, and what it will be in the future.  Understanding their dynamics is key to deeper understanding of the Gulf.

Personal Log

The schedule along the Seward Line and as we head to the Kodiak Line had to be adjusted due to rough seas and heavy winds.  This means we have been working variable and often long hours on the night shift. It is usually wet and cold and dark, and when it is windy the seawater we use to hose down the zooplankton nets seems to always spray into our faces and make its way into gloves and up sleeves.  But we still manage to have plenty of fun on the night shift and share lots of laughs.  There are also moments where I look up from the task at hand and am immersed in beauty, wonder, and fascination. I get to watch jellies undulate gracefully off the stern (all the while, crossing my fingers that they don’t end up in our nets  — that is bad for both them and us) and peer more closely at the zooplankton we’ve caught.  I am mesmerized by the color and motion of the breaking waves on a cloudy dawn and delighted by the sun cascading orange-pink towards the water at sunset.  I am reminded of my love, both emotional and intellectual, for the ocean!

Float coats
We experienced a lot of wind, rain, waves, and spray from the high-pressure hose (especially when I was wielding the hose), but bulky float coats kept us mostly warm and dry.

Did You Know?

Iron is the limiting nutrient in many offshore ecosystems.  Where there is more iron, there is generally more primary productivity and overall productive ecosystems.  Where there is little iron, very little can grow.  This is different than terrestrial and even coastal ecosystems, where iron is plentiful and other nutrients (nitrogen, phosphorous) tend to be the limiting factors.  Because people worked from what they knew in terrestrial ecosystems, until about 30 years ago, nitrogen and phosphorous were understood to be the important nutrients to study.  It was groundbreaking when it was discovered that iron may be a crucial piece of the puzzle in many open ocean ecosystems.

Question of the Day:

Regarding sustainability and scalability of intensive ocean resource harvesting: If humans started eating plankton directly, what could happen? And a follow-up: Can we use algae from harmful bloom areas?

Question from Leah Lily, biologist, educator, and qualitative researcher, Bellingham, WA

I first shared this question with the zooplankton night crew.  The consensus was that it was not a good idea to harvest zooplankton directly for large-scale human consumption.  Some krill and other zooplankton are already harvested for ‘fish oil’ supplements; as demand increases, the sustainability of this practice has become more dubious.  The zooplankton night crew were concerned that if broader-scale zooplankton harvest were encouraged, the resource would quickly be overharvested, and that the depletion of zooplankton stocks would have even more deleterious consequences for overall ecosystem function than the depletion of specific stocks of fish. They also brought up the question of how much of each zooplankton would actually be digestible to humans.  Many of these organisms have a chitinous exoskeleton, which we wouldn’t be able to get much nutrition from.  So it seems like intensive ocean harvesting of zooplankton is likely not advisable.

However, when I talked with the lead phytoplankton researcher on board, she thought there might be slightly more promise in harvesting phytoplankton.  It is more unlikely, she thinks, that it would get rapidly depleted since there is so much phytoplankton out there dispersed across a very wide geographic scale.  Generally, harvesting lower on the food chain is more energy efficient. At every trophic level, when one organism eats another, only a fraction of the energy is utilized to build body mass. So the higher up the food web we harvest from, the more energy has been ‘lost’ to respiration and other organism functions.  Harvesting phytoplankton would minimize the amount of energy that has been lost in trophic transfer.  Unlike most zooplankton, most phytoplankton is easily digestible to people and is very rich in lipids and proteins.  It could be a good, healthy food source.  However, as she also pointed out, harvesting phytoplankton in the wild would likely require a lot of time, energy, and money because it is generally so sparse.  It likely would not be economically feasible to filter the plankton in the ocean out from the water, and, with current technologies, not particularly environmentally friendly.  Culturing, or ‘farming,’ phytoplankton might help to address these problems, and in fact blue-green algae/Spirulina is already grown commercially and available as a nutritional supplement.  And there may be some coastal places where ‘wild’ harvest would be practical.  There are a number of spots where excess nutrients, often from fertilizers applied on land that runoff into streams and rivers, can cause giant blooms of phytoplankton.  These are often considered harmful algal blooms because as the phytoplankton die, bacteria utilize oxygen to decompose them and the waters become hypoxic or anoxic.  Harvesting phytoplankton from these types of harmful algal blooms would likely be a good idea, mitigating the impacts of the HABs and providing a relatively easy food source for people.  However, it would be important to make sure that toxin-producing plankton, such as Alexandrium spp. (which can cause paralytic shellfish poisoning) were not involved in the HAB.

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Mark Van Arsdale: What Makes Up an Ecosystem? Part II – Phytoplankton, September 14, 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 14, 2018

 

Weather Data from the Bridge

Mostly cloudy, winds variable 10 knots, waves to four feet

58.27 N, 148.07 W (Gulf of Alaska Line)

 

Science Log

What Makes Up an Ecosystem?  Part II Phytoplankton

Most of my students know that the sun provides the foundational energy for almost all of Earth’s food webs.  Yet many students will get stumped when I ask them, where does the mass of a tree comes from?  The answer of course is carbon dioxide from the air, but I bet you already knew that.

Scientists use the term “primary productivity” to explain how trees, plants, and algae take in carbon dioxide and “fix it” into carbohydrates during the process of photosynthesis.  Out here in the Gulf of Alaska, the primary producers are phytoplankton (primarily diatoms and dinoflagellates). When examining diatoms under a microscope, they look like tiny golden pillboxes, or perhaps Oreos if you are feeling hungry.

Primary productivity experiments running on the back deck of the Tiglax.
Primary productivity experiments running on the back deck of the Tiglax.

One of the teams of scientists on board is trying to measure the rates of primary productivity using captive phytoplankton and a homemade incubation chamber. They collect phytoplankton samples, store them in sealed containers, and then place them into the incubator.  Within their sample jars, they inject a C13 isotope.  After the experiment has run its course, they will use vacuum filtration to separate the phytoplankton cells from the seawater.  Once the phytoplankton cells are captured on filter paper they can measure the ratios of C12 to C13. Almost all of the carbon available in the environment is C12 and can be distinguished from C13.  The ratios of C12 to C13 in the cells gives them a measurement of how much dissolved carbon is being “fixed” into sugars by phytoplankton.  Apparently using C14  would actually work better but C14 is radioactive and the Tiglax is not equipped with the facilities to hand using a radioactive substance.

During the September survey, phytoplankton numbers are much lower than they are in the spring.  The nutrients that they need to grow have largely been used up.  Winter storms will mix the water and bring large amounts of nutrients back to the surface.  When sunlight returns in April, all of the conditions necessary for phytoplankton growth will be present, and the North Gulf of Alaska will experience a phytoplankton bloom.  It’s these phytoplankton blooms that create the foundation for the entire Gulf of Alaska ecosystem.

Personal Log

Interesting things to see

The night shift is not getting any easier.  The cumulative effects of too little sleep are starting to catch up to me, and last night I found myself dosing off between plankton tows.  The tows were more interesting though.  Once we got past the edge of the continental shelf, the diversity of zooplankton species increased and we started to see lantern fish in each of the tows.  Lantern fish spend their days below one thousand feet in the darkness of the mesopelagic and then migrate up each night to feed on zooplankton.  The have a line of photophores (light producing cells) on their ventral sides.  When they light them up, their bodies blend in to the faint light above, hiding their silhouette, making them functionally invisible.

A lantern fish with its bioluminescent photophores visible along its belly.
A lantern fish with its bioluminescent photophores visible along its belly.

Once I am up in the morning, the most fun place to hang out on the Tiglax is the flying bridge.  Almost fifty feet up and sitting on top of the wheelhouse, it has a cushioned bench, a wind block, and a killer view.  This is where our bird and marine mammal observers work.  Normally there is one U.S. Fish and Wildlife observer who works while the boat is transiting from one station to the next.  On this trip, there is a second observer in training.  The observers’ job is to use a very specific protocol to count and identify any sea bird or marine mammal seen along the transect lines.

Today we saw lots of albatross; mostly black-footed, but a few Laysan, and one short-tailed albatross that landed next to the boat while were casting the CTD.  The short-tailed albatross was nearly extinct a few years ago, and today is still considered endangered. That bird was one of only 4000 of its species remaining.  Albatross have an unfortunate tendency to follow long-line fishing boats.  They try to grab the bait off of hooks and often are drowned as the hooks drag them to the bottom.  Albatross are a wonder to watch as they glide effortlessly a few inches above the waves.  They have narrow tapered wings that are comically long. When they land on the water, they fold their gangly wings back in a way that reminds me of a kid whose growth spurts hit long before their body knows what to do with all of that height.   While flying, however, they are a picture of grace and efficiency.  They glide effortlessly just a few inches above the water, scanning for an unsuspecting fish or squid.  When some species of albatross fledge from their nesting grounds, they may not set foot on land again for seven years, when their own reproductive instincts drive them to land to look for a mate.

Our birders seem to appreciate anyone who shares their enthusiasm for birds and are very patient with all of my “What species is that?” questions.  They have been seeing whales as well.  Fin and sperm whales are common in this part of the gulf and they have seen both.

A Laysan Albatross
A Laysan Albatross, photo credit Dan Cushing

 

Did You Know?

Albatross, along with many other sea birds, have life spans comparable to humans.  It’s not uncommon for them to live sixty or seventy years, and they don’t reach reproductive maturity until well into their teens.

 

Animals Seen Today

  • Fin and sperm whales
  • Storm Petrels, tufted puffins, Laysan and black-footed and short-tailed albatross, flesh footed shearwater

 

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Martha Loizeaux: Spectrophotometers and Eggplant Curry, August 28, 2018

NOAA Teacher at Sea

Martha Loizeaux

Aboard NOAA Ship Gordon Gunter

August 22-31, 2018

Mission: Summer Ecosystem Monitoring Survey
Geographic Area of Cruise: Northeast Atlantic Ocean
Date: August 28, 2018

Weather Data from the Bridge

  • Latitude:  39.487 N
  • Longitude:  73.885 W
  • Water Temperature: 25.2◦C
  • Wind Speed:  13.1 knots
  • Wind Direction: WSW
  • Air Temperature: 26.1◦C
  • Atmospheric Pressure:  1017.28 millibars
  • Depth:  30 meters

Science and Technology Log

spectrophotometer
This is the underwater spectrophotometer!

“Underwater spectrophotometer”… say that 10 times fast!  I was lucky enough to steal a few minutes of Audrey Ciochetto’s time while we admired the views from the fly bridge today.  Audrey works with the Colleen Mouw Lab at the University of Rhode Island.  Her lab studies phytoplankton (you may remember that phytoplankton is plankton that is like a plant) and how light from the sun interacts with plankton.  I bet you never thought about that!  It’s amazing stuff!

Audrey and a graduate student from the lab, Kyle Turner, have brought another cool science tool on board, an underwater spectrophotometer.  The ship has pipes hooked up that take water in from 4 meters under the surface of the ocean at a constant flow.  This water goes into the spectrophotometer and the machine gets to work.  It shines light through the water and measures how the light is absorbed (taken in).  Did you know that light travels in waves?  Different colors of light that you see are different wavelengths.  The spectrophotometer can measure 83 different color wavelengths and what happens to them when they shine on the water.

What does happen to light when it shines into the water?  First of all, the water itself absorbs some of the light.  There are also a lot of tiny things in the water that absorb light.  Can you think of some tiny things that might be in the water? You guessed it again!  Phytoplankton is absorbing some of the light, but also other things like tiny particles and dissolved matter will absorb light.  These items will also scatter the light, making it bounce in different directions.  The underwater spectrophotometer measures that too!

filtering Audrey
Audrey filtering water samples to separate particles and plankton

Audrey and Kyle spend some of their day taking samples of the water and filtering out the plankton and particles, leaving only the dissolved matter.  They will also bring some sea water samples back to their lab to separate the phytoplankton from the rest of the particles. By separating all of these factors, scientists can get an idea of how each of these components in the water are responding to light.

The goal of this work is to understand what satellites are seeing.  Scientists rely on satellites out in space to take pictures of what’s happening on Earth.  These satellites can detect the light from the sun shining on Earth.  They can see some color wavelengths as they are absorbed or scattered by different things on our planet.  With the work that Audrey and Kyle are doing, we can better understand the satellite pictures of the ocean and what they mean.  We can understand what’s in the ocean by looking at what the sunlight is doing when it touches the water.  Pretty incredible, right?

The Design of Experiments

Hearing all of these brilliant ideas from Audrey got me thinking about how creative scientists must be to design experiments and investigations to answer questions.
Remember the hypothesis example that Chief Scientist Harvey mentioned in his interview?  It was an idea that scientists came up with after they used monitoring data to discover a pattern of lower populations of herring (fish).

Hypothesis:  “Increasing haddock populations lead to a lower stable state of herring because haddock feed on herring eggs.”

fish stomach contents
Scientists can study the stomach contents of fish to learn what they are eating. Photo courtesy of The Fisherman Magazine.

How would you design an experiment to test this?
Well, the real scientists who did this work examined the stomach contents of haddock to see how much of their diet consisted of herring eggs!  Would you have thought of that?
It was interesting to read about this study in a scientific journal called PNAS (it stands for Proceedings of the National Academy of Sciences), “Role of egg predation by haddock in the decline of an Atlantic herring population.” By Richardson et. al.

Get creative and start thinking of your own ideas to answer questions you have about the world!

 

 

Scientist Spotlight – Tamara Holzwarth-Davis, Physical Science Technician

Tamara is the physical science technician for NOAA National Marine Fisheries Service (NMFS) at Woods Hole.  A technician is someone who is an expert on the equipment and technology used by the scientists.  Today I had a chance to ask Tamara some more questions about her work.

Me – Tell me more about your job.
Tamara – I provide quality control for all of the data brought back by all of the ships involved in our study.  A lot of it is statistical analysis of data [this means looking at data and making sure that it makes sense and is accurate].  I calibrate sensors [make sure they are accurate], process data, and write reports based on the data we find.  We create a yearly atlas of information based on our data that anyone can use to look for trends (such as changes in plankton populations).  I also maintain and coordinate equipment that is needed for the studies.

Me – What part of your job with NOAA did you least expect to be doing?Tamara – I least expected to be so involved with plankton!  I used to do only the hydrography (water chemistry and physical properties) but now I am also involved with plankton data collection.

Tamara on watch
Tamara keeps track of a lot of different things during her watch.

Me – How do you help other people understand and appreciate NOAA’s work?
Tamara – I write the reports and make data available to the public.  People can be reassured that quality control is in place in our monitoring and the data is as accurate as possible.  It is my job to make sure of it!

Me – What do you love about going out to sea?
Tamara – I love the experience of being out at sea and meeting new people!

Personal Log

Our days on the ship are spent collecting data at stations, storytelling and watching the water on the fly bridge, catching up on work, watching sunrises and sunsets.  I’ve been pleasantly surprised by the comfort and commodities (like comfy mattresses and hot showers) and especially, THE FOOD!

food
The food options are outstanding. One night we had king crab legs and tuna steaks.

Margaret chef
Margaret is the best chef EVER.

Here on NOAA Ship Gordon Gunter, we have a wonderful steward staff (cooks and kitchen managers), Margaret and Paul. They always have smiles on their faces when you walk in for meal time and are happy to spread their cheerfulness.  There is always an amazing menu with many items to choose from.  As a vegetarian, I have been blown away by all of the delicious veggie options.  But there is plenty of meat for the carnivores too!  There are always a variety of snacks available as well as healthy options.

Margaret makes homemade cookies and pies, guacamole, crab salad, and eggplant curry, just to name a few.  We all sit down for meals together and share stories.  And there is always dessert!

Did You Know?

Water absorbs red light first.  So, if a fish has red scales when it’s out of the water, under water he will look brown and blend in to his surroundings.  All of the red light will have already been absorbed by the water and there won’t be enough left to reflect off the fish’s scales!

squirrelfish
A squirrelfish can blend in to its surroundings under water. Since it is a red fish, it is hard to see its color since the water has already absorbed the red light from the sun. Photo courtesy of NOAA.

Animals Seen Today

Common dolphins, green sea turtle, brown booby bird, larval hake, larval flounder, larval sea bass, jellyfish

brown booby
Bobby the brown booby stayed with our ship for several hours.

jellyfish jar
A jellyfish we caught in the plankton net!

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Martha Loizeaux: Cool Science Tools and Drifter Buoy! August 26, 2018

NOAA Teacher at Sea

Martha Loizeaux

Aboard NOAA Ship Gordon Gunter

August 22-31, 2018

 

Mission: Summer Ecosystem Monitoring Survey

Geographic Area of Cruise: Northeast Atlantic Ocean

Date: August 26, 2018

 

Weather Data from the Bridge

  • Latitude: 39.487 N
  • Longitude: 73.885 W
  • Water Temperature: 25.2◦C
  • Wind Speed: 13.1 knots
  • Wind Direction: WSW
  • Air Temperature: 26.1◦C
  • Atmospheric Pressure: 1017.28 millibars
  • Water depth:  30 meters

Science and Technology Log

As if catching plankton and sneaking a peak with the microscope wasn’t exciting enough (see the picture of the larval eel!), there’s a lot more data being collected on this ship. All of it helps scientists understand what’s going on in this part of the Ocean. And some of it I am able to help with, which is my favorite thing about this cruise (well, maybe that and the incredible views).

microscope and eel
I was able to examine some of the plankton samples with a microscope. Do you see the larval eel in the tray next to the scope?

niskin rosette
The CTD rosette and niskin bottles

At some of our stations, we lower a big and important science tool (called a rosette) into the ocean that contains niskin bottles (bottles used for water sampling) and a Conductivity, Temperature, and Depth meter (CTD). As the rosette is lowered into the depths and raised back up, the scientists can remotely operate the open niskin bottles to snap shut at specific depths. This allows each bottle to come up to the surface with a sample of water from many different depths! Meanwhile, the CTD can take measurements of conductivity (which indicates the salinity of the water), temperature, and pressure, among other things. Scientists have thought of many ways to collect A LOT of data at one time.

CTD coming up
Bringing the CTD up from the depths.

When the CTD comes back onto the ship, it’s time for us to use the samples for different purposes. We collect water from 3 different bottles (so 3 different depths) to test the amount of chlorophyll in the water. Do you know what the chlorophyll comes from? If you said plants, you’re right! What are some plant-like things that are drifting all over the ocean? You guessed it! Phytoplankton! So the amount of chlorophyll gives scientists evidence as to how much phytoplankton is in the water. But first, we need to extract (take out) the chlorophyll from the water. We run the water through special filters and soak the filters in a chemical that extracts the chlorophyll. Then we can put the sample through a special machine that uses light to sense the amount of chlorophyll. Wow. One thing I am learning on this trip is how important light is in understanding a water ecosystem.

extracting chlorophyll
Me extracting chlorophyll samples

Do you remember what a hypothesis is? It’s an educated guess that answers a scientific question. When scientists come up with a hypothesis, it gives them something to test in an investigation. If you were presented with the question, “At what depth is phytoplankton most abundant?”, what would be your hypothesis?

Another thing we do with the water samples is collect a bit from most of the bottles to preserve and send to the lab to test for the amount of nutrients. When you think of nutrients, you probably think of healthy vitamins for people. But nutrients for plants are actually made from broken down waste of animals. It’s important for ocean water to have a balanced amount of nutrients so that phytoplankton can be healthy. But too much nutrients can also cause algae and phytoplankton to overpopulate!
But that’s not all! The scientists also take samples from the niskin bottles to test for Dissolved Inorganic Carbon (DIC). That sounds fancy, I know. Doing this basically helps scientists understand the pH of the water and look for evidence of ocean acidification (a result of climate change).

nutrient samples
Jessica and I taking nutrient samples from the niskin bottles

Can you believe how much scientists can learn from dropping a big science tool into the water?
Scientist Spotlight – Harvey Walsh
Harvey is our Chief Scientist on the mission, meaning he oversees all of the scientific work happening on the ship.  He has been so kind as to answer all of my many questions, including these:
Me – If you could invent any tool to make your work more efficient, what would it be and why?
Harvey – I would like a tool that allows you to easily and quickly identify fish eggs and larvae.  Currently, it is a time consuming process that involves sorting through samples and identifying them in the lab.  There have been and continue to be efforts to use image analysis and genetics to speed up the process.  An image analysis has progressed quicker for phyto- and zooplankton, but fish and fish eggs still lag behind.
Me – When did you know you wanted to pursue a career in ocean science?
Harvey – I always thought I would end up studying freshwater fisheries in Minnesota, where I grew up, but after the first two ocean cruises I participated in, I knew the ocean was more for me and the lakes had less of an appeal.
Me – How long has EcoMon (the ecosystem monitoring program we are using) been conducted and how was the protocol (the methods we use) created?

Harvey – EcoMon started in 1992 but it was modeled after a program that started in 1977.  The bongo plankton sampling has not changed much since it started, but with new technology we have added the water chemistry

Harvey chief scientist
Harvey relaxing in the bridge deck

testing, optics, and other instruments.

To create the protocol, scientists from around the North Atlantic region got together to form the International Commission for the Northwest Atlantic Fisheries.  This council had the job of looking at plankton sampling techniques and deciding the best way to monitor plankton communities.
Me – Can you share an example of a way that people have used EcoMon data to form and test a hypothesis?
Harvey – Our data helps scientists make connections between different species in a food web, for example.  After people noticed that Atlantic herring (fish) populations were getting low, they used EcoMon data to come up with a hypothesis like this:
“Increasing haddock populations lead to a lower stable state of herring because haddock feed on herring eggs.”
If people want to know more about a certain species of fish and how it survives and thrives, they need to understand the whole ecosystem, including the food web!
Personal Log
This cruise continues to amaze me. Sometimes we’ll have several hours between stations when I love to learn from others, bring a pair of binoculars up to the fly bridge and join the seabird observers, or catch up on a good book. Being around the water all day is calming and serene. I feel that this is the opportunity of a lifetime.

Martha and drifter
Me and the NOAA Drifter Buoy decorated for Ocean Studies Charter School!

Another rare opportunity came yesterday when I was able to launch my drifter buoy as part of the NOAA drifter buoy program! First, I decorated the buoy with our school’s name and a symbol for each of the classes at our school – the Sharks class, the Rays class, the Dolphin class, and the Sea Star class. Then, after gaining permission from the ship command, we dropped the buoy overboard!
The buoy has a long canvas tube that extends out like a spring after you release it. This allows the buoy to have a long tail that reaches into the water so that it can catch the ocean currents and drift. If it was just the floating buoy, it would get moved by the wind instead of the currents.

people on bow
Everyone runs to the bow when dolphins are riding the wake!

The buoy has a satellite tag that sends a signal to a satellite wherever it goes. This way, back home my students and I can track the buoy online and see where it ends up! Where do you think the buoy will go?
Everyone on board gets excited when we spot a pod of dolphins or a whale spout! I can’t wait to see what’s out there tomorrow!
Did You Know?
Great Shearwaters are sea birds that spend most of their lives out at sea and only come to land to nest. They can dive deep to catch fish but do not have to dry out their wings like some other birds. They are almost always found soaring by air currents and they prefer stormy and rough weather for stronger air patterns to lift them up.

A great shearwater in flight. Photo courtesy of NOAA.

Challenge Yourself
If a plankton sample with 5,000 individual plankton contains 60% salps, 10% hake larvae, 20% arrow worms, and 10% crab megalops, how many arrow worms are in the sample?

arrow worm
Here’s a picture of an arrow worm from under a microscope. They are about the size of the letter “I” on your keyboard. Photo courtesy of NOAA.

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Susan Dee: Microscopic Sea Life – Days 1-4, May 24, 2018

NOAA Teacher at Sea
Susan Dee
Aboard NOAA Ship Henry B. Bigelow
May 23 – June 7, 2018

Mission:  Spring Ecosystem Monitoring Survey

Geographic Area of Cruise:  Northeastern Coast U.S.
Date: May 24, 2018
Weather Data from Bridge
Latitude: 40°32′
Longitude: 070°45′
Sea Wave Height:  1-2 feet
Wind Speed:  12 knots°
Wind Direction: west
Viability: unrestricted
Air Temperature:  13.5°C
Sky: Few clouds

Science and Technology Log

Tuesday, May 22, I arrived at Newport Naval Base and boarded NOAA Ship Henry B. Bigelow to begin my Teacher at Sea journey by staying overnight on a docked ship.   Day 1 was filled with many new experiences as we headed out to sea.  The Henry B. Bigelow is part of a fleet of vessels commissioned to conduct  fishery surveys. To learn more about the Henry B. Bigelow,  check out this website:  Henry B. Bigelow. The objective of this cruise is to access the hydrographic, planktonic and pelagic components of North East U.S. continental shelf ecosystem.  The majority of the surveys we will take involve  the microbiotic parts of the sea –  phytoplankton, zooplankton and mesoplankton.  Plankton are small microscope organisms in the oceans that are extremely important to the entire Earth ecosystem.  These organisms are the foundation of the entire ocean food web. By studying their populations. scientists can get an accurate picture of the state of  larger ocean organism populations.

Susan and ship
Henry B. Bigelow

Leaving Newport Harbor
Leaving Newport Harbor

Before leaving the dock, I met with Emily Peacock from Woods Hole Oceanographic Institute (WHOI) to learn how to run an Imaging Flow Cytobot instrument that uses video and flow cytometric technology to capture images of phytoplankton. The IFCB was developed by Dr Heidi Sosik and Rob Olsen (WHOI) to get a better understanding of coastal plankton communities. The IFCB runs 24 hours a day collecting sea water and continuously measuring phytoplankton abundance.  Five milliliters of sea water are analyzed every 20 minutes and produces the images shown below.

Imaging Flow CytoBot
Emily Peacock teaching the usage of the Imaging Flow CytoBot (IFCB)

 

Imaging Flow Cytobot IFCB
Imaging Flow Cytobot (IFCB)

phytoplankton
Images of Phytoplankton taken by IFCB

The science party on board is made up of scientists from National Marine Fisheries Service (NMFS) part of NOAA Fisheries Division. The chief scientist, Jerry Prezioso, works out of Narragansett Lab and the lead scientist, Tamara Holzworth Davis, is from the Woods Hole Lab, both from the NOAA Northeast Fisheries Science Center.  Other members of the Science Party are Seabird/Marine Mammal observers and a student  from Maine Maritime Academy.  The Crew and scientist group work together to coordinate sampling stations. The crew gets the ship to the site and aid the scientists in deploying instruments. The scientists collect the data and samples at each station.  The Crew and scientists work together to find the best and most efficient sea route to each  sampling site. Note all the stops for specimen collection on map below. There definitely  has to be a plan!

map of proposed route
Proposed Cruise Track and Survey Locations

 

Personal Log

Because research instrument deployment is done 24 hours a day, the NOAA Corps crew and scientists are divided into two shifts. I am on watch 1200 – 2400 hours, considered the day shift. This schedule is working good for me. I finish duty at midnight, go to sleep till 9:00 AM and rise to be back on duty at noon. Not a bad schedule. Due to clear weather and calm seas, the ship headed east out of Newport Harbor towards the continental shelf and started collecting samples at planned stops.   I joined another group of scientists  observing bird and marine mammal populations from the flying bridge of the ship. Humpback whales and basking sharks breached  several times during the day

It has only been two days but I feel very acclimated to life at sea. I am not seasick, thanks to calm seas and the patch. Finding the way around the ship is getting easier- it is like a maze. Spotting a pod of humpback whales breaching and basking sharks was a highlight of the day. My Biology students back at May River  High School scored great on End of Course Exam. Congratulations May River High School Sharks! Thinking of y’all.

school logo
Love My SHARKS!

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Chelsea O’Connell-Barlow: Full Steam Ahead, August 30, 2017

NOAA Teacher at Sea

Chelsea O’Connell-Barlow

Aboard NOAA Ship Bell M. Shimada

August 29 – September 12, 2017

 

Mission: Pacific Hake Survey

Geographic Area of Cruise: NW Pacific Ocean

Date: 8/30/2017

 

Weather Data from the Bridge:

Latitude: 48.472837N

Longitude: -124.676694W

Temperature 59 F

Wind 9.7 knots

Waves 3-5 feet

Science and Technology Log

We have not started fishing yet because we are heading to our first transect off the western coast of the Haida Gwaii archipelago. I thought this would be a perfect time to introduce another research project that is gathering data on the Shimada. One of my roommates, Lynne Scamman, is on-board researching Hazardous Algal Blooms (HABs).

Lynne in Chem lab
Lynne Scamman running wet chemistry tests and identifying phytoplankton.

  1. What are Hazardous Algal Blooms?

They are large numbers of phytoplankton, either diatoms or dinoflagellates, who produce toxins. Phytoplankton are essential to the ecosystem because they produce half of the global oxygen. However under certain circumstances these organisms reproduce rapidly, skyrocketing the population, this is a bloom. Some of these phytoplankton produce toxins. When the populations are low the toxins aren’t a big deal. However, when a bloom of phytoplankton that produce toxins occurs there can be health concerns for organisms exposed to the toxins. We have to consider the marine food chain and something called bioaccumulation. Phytoplankton along with zooplankton create the base of the marine food web. Organisms who eat toxin producing phytoplankton retain the toxin in their body. Then any organism who eats them will also hold that toxin. You can see how the toxin would accumulate along the food chain and potentially hold serious side effects for organisms with high levels of toxin.

  1. Why is research being done on HABs?

HABs are becoming a problem for humans along the coasts and in the Great Lakes. Basically all of the factors that contribute to the increase in HABs are a product of human impact. Global climate change, increased nutrient pollution and global sea trade are all factors contributing to the rise in Hazardous Algal Blooms. We want to monitor so that eventually we will be able to predict when, where and why the HABs will occur.

  1. Why are YOU studying HABs?

One day I walked into my college biology lab and met a guest instructor who specializes in all things phytoplankton related. I was blown away by the complexity that some of these single celled organisms held. The professor shared a few species names and I started investigating. The species that grabbed my attention is called Nematadinium armatum. This organism has a rudimentary eye called a melanosome and nematocysts for hunting, again this is pretty impressive for an organism made of one cell. Once I learned about the variety in this microscopic world and how influential they were to the health of the entire ocean, I knew that I wanted to learn more.

Personal Log

I am still figuratively pinching myself every few hours at just how amazing this experience is to participate in first hand. Yesterday we left the dock of Port Angeles at 10am and the boat hasn’t slowed down since. We did drills to ensure that all aboard knew where to go in case of fire and if we needed to abandon ship. Part of the abandon ship drill is to make sure that everyone has and can get into their Immersion Suit aka “Gumby Suit.” This suit is amazing! This portion of the Pacific is quite cold and the Immersion suit would keep you warm and buoyant until a rescue can occur.

OCB Gumby
Trying on the Immersion suit.

After our drills several of the science crew went up to the Flying Bridge to look for marine mammals. We were cruising between Cape Flattery, Washington and Vancouver Island, British Columbia with high hopes of seeing activity. WOW, we lucked out. We spotted 17 Humpback whales, 2 Harbor porpoise and 2 Dall’s porpoise. We are also seeing several types of sea birds but I am still brushing up with the Sibley to id birds from this area.

Shimada Flags
The Shimada under two flags as it enters Canadian waters.

 

Did You Know?

The island cluster that we are heading to had a name change at the end of 2009. What was formerly called Queen Charlotte Islands is now called Haida Gwaii. This name change came as part of a historic reconciliation between British Columbia and Haida nation. Haida Gwaii translated means “island of the people.”

Haida Gawaii
Map of Haida Gawaii area.

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Amanda Dice: Ending Week 1 at Line 8, August 26, 2017

NOAA Teacher at Sea

Amanda Dice

Aboard Oscar Dyson

August 21 – September 2, 2017

 

Mission: Juvenile Pollock Fishery Survey

map cropped
Oscar Dyson moves across the Shelikof Straight to collect the Line 8 samples

Geographic area of cruise: Western Gulf of Alaska

Date: August 26, 2017

Weather Data: 13.2 C, cloudy with light rain

Latitude 57 36.6 N, Longitude 155 .008 N

 

 

Science and Technology Log

As part of this survey, the scientists onboard collect data from what is known as “Line 8”. This is a line of seven sampling stations, positioned only a few miles apart, near the southern opening of Shelikof Straight between Kodiak Island and the Alaskan Peninsula. Water samples are taken at different depths at each sampling station to measure several different properties of the water. This study is focused on profiling water temperature and salinity, and measuring the quantities of nutrients and phytoplankton in the water.

IMG_0988
The CTD rosette is lowered into the water using a winch – as seen from above.

To collect this data, a conductivity and temperature at depth (CTD) instrument is lowered into the water. This instrument can take water samples at different depths, by using its eleven canisters, or Niskin bottles. The water collected in the Niskin bottles will be used to determine the nutrient quantities at each station. The rosette of Niskin bottles also has sensors on it that measure phytoplankton quantities, depth, temperature, and how conductive the water is. Scientists can use the readings from conductivity and temperature meters to determine the salinity of the water.

Each Niskin bottle has a stopper at the top and the bottom. The CTD goes into the water with both ends of each Niskin bottle in the open position. The CTD is then lowered to a determined depth, depending on how deep the water is at each station. There is a depth meter on the CTD that relays its position to computers on board the ship. The survey team communicates its position to the deck crew who operate the winch to raise and lower it.

IMG_1164
Niskin bottles are lowered into the water with the stoppers at both ends open.

When the CTD is raised to the first sampling depth, the survey crew clicks a button on a monitor, which closes the stoppers on both ends of Niskin bottle #1, capturing a water sample inside. The CTD is then raised to the next sampling depth where Niskin bottle #2 is closed. This process continues until all the samples have been collected. A computer on board records the depth, conductivity and temperature of the water as the CTD changes position. A line appears across the graph of this data to show where each sample was taken. After the Niskin bottles on the CTD are filled, it is brought back onto the deck of the ship.

IMG_1173
They let me take control of closing the Niskin bottles at the sampling depths!

CTD screen cropped
I used this screen to read the data coming back from the CTD and to hit the bottle to close each Niskin bottle. The purple horizontal lines on the graph on the right indicate where each one was closed.

Water is collected through a valve near the bottom of each Niskin bottle. A sample of water from each depth is placed in a labeled jar. This study is interested in measuring the quantity of nutrients in the water samples. To do this it is important to have samples without phytoplankton in them. Special syringes with filters are used to screen out any phytoplankton in the samples.

Screen Shot 2017-08-26 at 8.28.56 PM
Syringes with special filters to screen out phytoplankton are used to collect water samples from the Niskin bottles.

The “Line 8” stations have been sampled for nutrient, plankton, and physical water properties for many years. The data from the samples we collected will be added to the larger data set maintained by the Ecosystems and Fisheries-Oceanography Coordinated Investigations (Eco-FOCI), Seattle, Washington. This NOAA Program has data on how the marine ecosystem in this area has changed over the last few decades. When data spans a long time frame, like this study does, scientists can identify trends that might be related to the seasons and to inter-annual variation in ocean conditions. The samples continue to be collected because proper nutrient levels are important to maintaining healthy phytoplankton populations, which are the basis of most marine food webs.

 

IMG_1171
Collecting water samples from a Niskin bottle.

Personal Log

As we travel from one station to the next, I have some time to talk with other members of the science team and the crew. I have really enjoyed learning about places all over the world by listening to people’s stories. Most people aboard this ship travel many times a year for their work or have lived in remote places to conduct their scientific studies. Their stories inspire me to keep exploring the planet and to always search for new things to learn!

Did you know?

Niskin bottles must be lowered into the water with both ends open to avoid getting an air bubble trapped inside of them. Pressure increases as depth under water increases. Niskin bottles are often lowered down below 150 meters, where the pressure can be intense. If an air bubble were to get trapped inside, the pressure at these depths would cause air bubble to expand so much that it might damage the Niskin bottle!

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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
Pseudonitzchia. Photo by National Ocean Service

Thalassiosira. Photo by: Department of Energy Joint Genome Institute
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
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
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
Rosette with the 12 Niskin Bottles and the CTD. Photo by DJ Kast

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

Up close shot of the water sampling. 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
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

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Todd with the manually operated Niskin Bottle. Photo by: DJ Kast
Todd with the manually operated Niskin Bottle. Photo by: DJ Kast

Manual CTD fully cocked and ready to deploy. 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
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
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
Filtering out only the water using a syringe filter. Photo by DJ Kast

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.

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DJ Kast, Interview with Emily Peacock, May 25, 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 25, 2015, Day 7 of Voyage

Interview with Emily Peacock

Emily Peacock and her ImagingFlowCytobot. Photo by: DJ Kast
Emily Peacock and her ImagingFlowCytobot. Photo by: DJ Kast

Emily Peacock is a Research Assistant with Dr. Heidi Sosik at the Woods Hole Oceanographic Institution (WHOI). She is using imaging flow-cytometry to document the phytoplankton community structure along the NOAA Henry B. Bigelow Route.

Why is your research important?

Phytoplankton are very important to marine ecosystems and are at the bottom of the food chain.  They uptake carbon dioxide (CO2) and through the process of photosynthesis make oxygen, much like the trees of the more well-known rain forests.

Ocean Food Chains. Photo by: Encyclopedia Britannica 2006 (http://media.web.britannica.com/eb-media/99/95199-036-D579DC4A.jpg)
Ocean Food Chains. Photo by: Encyclopedia Britannica 2006 (http://media.web.britannica.com/eb-media/99/95199-036-D579DC4A.jpg)

The purpose of our research is “to understand the processes controlling the seasonal variability of phytoplankton biomass over the inner shelf off the northeast coast of the United States. Coastal ocean ecosystems are highly productive and play important roles in the regional and global cycling of carbon and other elements but, especially for the inner shelf, the combination of physical and biological processes that regulate them are not well understood.” (WHOI 2015)

What tool do you use in your work you could not live without?

I am using an ImagingFlowCytobot (IFCB) to sample from the flow-through Scientific Seawater System.

ImagingFlowCytobot. Photo: DJ Kast
ImagingFlowCytobot. Photo: DJ Kast

Inside of the ImagingFlowCytobot. Photo by Taylor Crockford
Inside of the ImagingFlowCytobot. Photo by Taylor Crockford

The green tube is what collects 5 ml into the ImagingFlowCytobot. Photo by: DJ Kast
The green tube is what collects 5 ml into the ImagingFlowCytobot. Photo by: DJ Kast

IFCB is an imaging flow cytometer that collects 5 ml of seawater at a time and images the phytoplankton in the sample. IFCB images anywhere from 10,000 phytoplankon/sample in coastal waters to ~200 in less productive water. Emily is creating a sort of plankton database with all these images. They look fantastic, see below for sample images!

Microzooplankton called Ciliates. Photo Credit: IFCB, from this Henry Bigelow research cruise.
Microzooplankton called Ciliates. Photo Credit: IFCB, from this Henry Bigelow research cruise.

Dinoflagellates Photo Credit: IFCB, from this Henry Bigelow research cruise.
Dinoflagellates
Photo Credit: IFCB, from this Henry Bigelow research cruise.

The IFCB “is a system that uses a combination of video and flow cytometric technology to both capture images of organisms for identification and measure chlorophyll fluorescence associated with each image.  Images can be automatically classified with software, while the measurements of chlorophyll fluorescence make it possible to more efficiently analyze phytoplankton cells by triggering on chlorophyll-containing particles.” (WHOI ICFB 2015). 

What do you enjoy about your work?

I really enjoy looking at the phytoplankton images and identifying and looking for more unusual images that we don’t see as often. I particularly enjoy seeing plankton-plankton interactions and grazing of phytoplankton.

Grazing (all photo examples are not from this research cruise but still from an IFCB):

Small flagellates on a Thallasiosira Photo Credit: MVCO
Small flagellates on a Thallasiosira (Diatom) Photo Credit: IFCB at MVCO

Diatom with a dino eating it from the outside (peduncle).Photo Credit: MVCO
Diatom with a dinoflagellate eating it from the outside using a peduncle (feeding appendage). Photo Credit: IFCB at MVCO

Engulfer- Gyrodinium will engulf itself around the diatom (Paralia consumed by Gyrodinium).Photo Credit: MVCO
Engulfer- Gyrodinium will engulf the diatom Paralia Photo Credit: IFCB at MVCO

Dinoflagellates Pallium feeder- feeding externally, the pallium wraps around the prey.Photo Credit: MVCO
Dinoflagellates pallium feeding externally, the pallium (cape-like structure, think of saran wrap on food) wraps around the prey. Photo Credit: IFCB at MVCO

What type of phytoplankton do you see?

I am seeing a lot of dinoflagellates in the water today (May 20th, 2015), Ceratium specifically.

Ceratium. Photo by IFCB at MVCO
Ceratium. Photo by IFCB at MVCO

The most common types of plankton I see are: diatoms, dinoflagellates, and microzooplankton like ciliates. The general size range for the phytoplankton I am looking at is 5-200 microns.

Colonial choanoflagellate. Photo Credit: MVCO
Colonial choanoflagellate. Photo Credit: IFCB at MVCO

Where do you do most of your work?

“The Martha’s Vineyard Coastal Observatory (MVCO) is a leading research and engineering facility operated by Woods Hole Oceanographic Institution. The observatory is located at South Beach, Massachusetts and there is a tower in the ocean a mile off the south shore of Martha’s Vineyard where it provides real time and archived coastal oceanographic and meteorological data for researchers, students and the general public.” (MVCO 2015).

Screen Shot 2015-05-20 at 1.54.39 PM
MVCO Photo from: http://www.whoi.edu/mvco

Most of my work with Heidi is at the Martha’s Vineyard Coastal Observatory. IFCB at MVCO has sampled phytoplankton every 20 minutes since 2006 (nearly continuously). This unique data set with high temporal resolution allows for observations not possible with monthly or weekly phytoplankton sampling.

Below is an example from the MVCO from about an hour ago at 1 PM on May 20th, 2015.

Photo Credit: MVCO
Photo Credit: IFCB at MVCO

Did you know??

IFCB at Martha’s Vineyard Coastal Observatory has collected photos of nearby phytoplankton every 20 minutes since 2006 (9 years, almost continuously). With this time series, you can study changes in temporal and seasonal patterns in phytoplankton throughout the years.

Helpful Related links:

Current Plankton at the MVCO:  demi.whoi.edu/mvco