Phil Moorhouse: The Rest of the Story, September 22, 2019

NOAA Teacher at Sea

Phil Moorhouse

Aboard NOAA Ship Oscar Dyson

August 27, 2019 – September 15, 2019


Mission: Fisheries-Oceanography Coordinated Investigations.

Geographic Area of Cruise: Gulf of Alaska (Kodiak – Aleutian Islands)

Date: September 22, 2019


Weather Data from Richmond, Virginia

Latitude: 37 44.36 N
Longitude: 77 58.26 W
Wind Speed: 5 knots
Wind Direction: 195 degrees
Air Temperature: 31 C
Barometric Pressure: 1018 mBar
Sky:  Clear

Conclusion

Wow, it’s hard to believe that my time on the waters of Alaska aboard the Oscar Dyson are over.  It was an experience I will never forget.  I just hope that I can instill in my students the idea that all kinds of things are possible when you follow your interests. 

It has taken me several days to reacclimatize to life on land.  Standing in front of my class, I have caught myself swaying.  It also took several days to readjust my sleep schedule.  (I don’t get rocked to sleep anymore and my hours are completely different.)

There were so many things I will miss and never forget: all of the unique experiences and sights I got to see, starting with my side trip to Barrow and swimming in the Arctic Ocean before the start of the expedition, getting to explore some of Kodiak before we left port, all of the open sea and species that were part of the random samples, the little coves we snuck into when storms were approaching, getting a “close-up” of the Pavlof volcano, and getting to explore the native land around Dutch Harbor where we were able to watch Salmon spawning and Bald Eagles doing their thing. 

It was also interesting talking to and learning from the ship crew.  There are some interesting stories there about how they got to NOAA and what they have experienced since then.

At the top of the list though would have to be the connections I made with the scientists I spent almost three weeks with.  Being able to go out into the field with them and talking about what they have seen and learned over years of research has really reenergized my love for science in general.  Starting my shift looking forward to seeing what each Bongo station would bring up or what each trawl would bring to the sorting table, made for an expedition that went much too quickly.  It was interesting listening to my fellow scientists comparing how the numbers and ages of pollock caught at the various stations compared to what they had found in the Spring and in previous years. 

airport meal
The science crew all had the chance for one last meal together at the Anchorage airport before parting ways. I am very thankful for being accepted so well and for everything I have learned.

Overall, this has been an experience I will never forget.  I have learned so much about Alaska, the ocean, marine species, global warming, and scientific technology.  My time as a Teacher at Sea aboard the Oscar Dyson is something I will never forget and hope I can pass the excitement and experiences on to my students.

Phil Moorhouse: Look What the Net Dragged In! September 12, 2019

NOAA Teacher at Sea

Phil Moorhouse

Aboard NOAA Ship Oscar Dyson

August 27 – September 15, 2019


Mission: Fisheries-Oceanography Coordinated Investigations.

Geographic Area of Cruise: Gulf of Alaska (Kodiak – Aleutian Islands)

Date: September 12, 2019

Weather Data from the Bridge

Latitude: 57 35.35 N
Longitude: 153 57.71 W
Sea wave height: 1 ft
Wind Speed: 14 knots
Wind Direction: 208 degrees
Visibility: 8 nautical miles
Air Temperature: 15.4 C
Barometric Pressure: 1002.58 mBar
Sky:  Overcast


Science and Technology Log

Well, we only have a few days left on this trip and it looks like mother nature is going to force us to head for Dutch Harbor a little early.  I thought this might be a good time to spend some time sharing some information on some of the species we have been pulling out of the ocean.  This is far from a complete list, but just the ones that made “the cut”.

At the top of the list has to be the Pollock.  After all, this is the primary objective of this study.  On the left is an adult three-year-old pollock and on the right is an age-0 pollock.  The sampling of age-0 pollocks is a good indicator of the abundance of the future population.

There were several species of salmon caught on our trawls.  On the left is a Coho Salmon and on the right is a Pink Salmon.  These fish are very similar, but are classified as separately Coho Salmon are larger and have larger scales.  Coho also has a richer, fuller flavor with darker red meat while the Pink Salmon has a milder flavor and a softer texture.

zooplankton
Another important part of this survey is the collection and measurement of zooplankton as this is a primary food source and the amount and health of the zooplankton will have a lasting impact on the ecology of the fish population in the area.
capelin
Capelin is another common fish caught in our trawls. This fish eats krill and other crustaceans and in turn is preyed upon by whales, seals, cod, squid, and seabirds.
Pacific Saury
The Pacific Saury was a fish that wasn’t expected to be found in our trawls. Also called the knifefish, this species always seemed to be found in substantial quantities when they were collected – as if the trawl net came across a school of them. They are found in the top one meter of the water column.
Prowfish
The Prowfish was another interesting find. This fish is very malleable and slimy. Adults tend to stay close to the ocean floor while young prowfish can be found higher up in the water column where they feed on jellyfish. As with the saury, the prowfish was not kept for future study. It was weighed, recorded, and returned to the water.

Jellyfish were abundant on our hauls.  Here are the five most common species that we found. 

bubble jellyfish
The Bubble Jellyfish, Aequorea sp., is clear with a rim around it. This jellyfish is fragile and most of them are broken into pieces by the time we get them from the trawl net and onto the sorting table.
moon jellyfish
The Moon Jellyfish, Aurelia labiata, is translucent and when the sun or moon shines on them, they look like the moon all lit up.
white cross jellyfish
The White Cross Jellyfish, Staurophora mertensi, was another mostly clear jelly that was very fragile. Very few made it to the sorting table in one piece. You have to look close it is so clear, but they can be identified by their clear bell with a distinctive X across the top of the bell.
Lion's mane jellyfish
The Lion’s Mane Jellyfish, Cyanea capillata, are the largest known species of jellyfish. These guys can become giants. They are typically a crimson red but could appear faded to a light brown.
sunrise jellyfish
The Sunrise Jellyfish, Chrysaora melanaster, was the most common jelly that we found. It is also arguably the least fragile. Almost all made it to the sorting table intact where they were counted, weighed, recorded, and returned to the water. It lives at depths of up to 100 meters, where it feeds on copepods, larvaceans, small fish, zooplankton, and other jellyfish.
arrowtooth flounder
Arrowtooth flounder are a relatively large, brownish colored flatfish with a large mouth. Just one look at its mouth and you can tell how it got its name. Their eyes migrate so that they are both on the right side and lie on the ocean floor on their left side.
Eulachon
Eulachons, sometimes called candlefish, were another common find on the sorting table. Throughout recent history, eulachons have been harvested for their rich oil. Their name, candlefish, was derived from it being so fat during spawning that if caught, dried, and strung on a wick, it can be burned as a candle. They are also an important food source for many ocean and shore predators.
vermilion rockfish
The Vermilion Rockfish – This guy was the only non-larval rockfish that we caught. Most can be found between the Bering Sea and Washington State.

While the Smooth Lumpsucker is significantly larger than the Spiny Lumpsucker, both have unique faces.  The Smooth Lumpsucker is also found in deeper water than the smaller Spiny Lumpsucker.

Most of the squid caught and recorded were larval.  Here are a couple of the larger ones caught in a trawl.

There were a variety of seabirds following us around looking for an easy meal.  The Black-footed Albatross on the right was one of several that joined the group one day.

Pavlof Volcano
And of course, I couldn’t leave out the great view we got of Pavlof Volcano! Standing snow capped above the clouds at 8,251 feet above sea level, it is flanked on the right by Pavlof’s Sister. Pavlof last erupted in March of 2016 and remains with a threat of future eruptions considered high. Pavlof’s Sister last erupted in 1786. This picture was taken from 50 miles away.


Personal Log

In keeping with the admiration I have for the scientists and crew I am working with, I will continue here with my interview with Rob Suryan. 

Robert Suryan is a National Oceanic and Atmospheric Administration Scientist. He is currently a Research Ecologist and Auke Bay Laboratories, Science Coordinator, working on the Gulf Watch Alaska Long-term Ecosystem Monitoring Program.

How long have you been working with NOAA?  What did you do before joining NOAA?

One and a half years.  Prior to that, I was a professor at Oregon State University

Where do you do most of your work?

In the Gulf of Alaska

What do you enjoy about your work?

I really enjoy giving presentations to the general public, where we have to describe why we are conducting studies and results to an audience with a non-science background. It teaches you a lot about messaging! I also like working with writers, reporters, and journalists in conducting press releases for our scientific publications. I also use Twitter for science communication.

Why is your work important?

Having detailed knowledge about our surroundings, especially the natural environment and the ocean. Finding patterns in what sometimes seems like chaos in natural systems. Being able to provide answers to questions about the marine environment.

How do you help wider audiences understand and appreciate NOAA science?

I provide information and expertise to make well informed resource management decisions, I inform the general public about how our changing climate if affecting marine life, and I train (and hopefully inspire) future generations of marine scientists

When did you know you wanted to pursue a career in science an ocean career?

During middle school

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

Computer! So much of our instrumentation and sampling equipment are controlled by software interfaces. Also, much of my research involves data assimilation, analysis, creating graphs, and writing scientific papers. Although, at the very beginning of my career, most of our data collection was hand written, as were our scientific papers before typing the final version with a typewriter. So glad those days are gone!

If you could invent one tool to make your work easier, what would it be?

For in the office: a computer program that would scan all of my emails, extract the important info that I need to know and respond to, and populate my calendar with meetings/events. For the field: a nano-power source that provided unlimited continuous power for instruments AND global cell phone or wireless connectivity.

What part of your job with NOAA did you least expect to be doing?

I joined NOAA later in my career and had collaborated with NOAA scientists for many years, so everything was what I expected for the most part.

What classes would you recommend for a student interested in a career in Marine Science?

Biology, math, chemistry, and physics are good foundation courses. If you have an opportunity to take a class in marine biology at your school or during a summer program, that would be ideal. But keep in mind that almost any field of study can be involved in marine science; including engineering, economics, computer science, business, geology, microbiology, genetics, literature, etc.

What’s at the top of your recommended reading list for a student exploring ocean or science as a career option?

I originally studied wildlife biology before marine science and one of my favorite books initially was A Sand County Almanac, by Aldo Leopold. For marine biology, I would recommend The Log from the Sea of Cortez, by John Steinbeck.

What do you think you would be doing if you were not working for NOAA?

I would probably work at a university again – I was a professor at Oregon State University before working for NOAA.

Do you have any outside hobbies?

Pretty much any type of outdoor adventure, most frequently kayaking, mountain biking, hiking, camping, and beachcombing with my family and our dogs.

Jessica Cobley: Not Just Fishing, August 1, 2019

NOAA Teacher at Sea

Jessica Cobley

Aboard NOAA Ship Oscar Dyson

July 19 – August 8, 2019


Mission: Midwater Trawl Acoustic Survey

Geographic Area of Cruise: Gulf of Alaska (Kodiak to Yakutat Bay)

Date: 8/1/2019

Weather Data from the Gulf of Alaska: Lat: 59º 18.59’ N Long: 146º 06.18W 

Air Temp:  14.8º C

Personal Log

We made it to Prince William Sound the other day, but I was asleep by the time we got all the way up. The part I did see, near the entrance, was pretty, but fog and clouds blocked the majority of the view. One of the beaches we attempted to fish by had what looked like an old red train car washed up on it. We wondered where it came from and how it got there!

Sunrise over Gulf of Alaska
Sunrise the day before we headed into Prince William Sound.

We are sailing the last few transects of the trip now and headed towards a small bay, called Broken Oar Bay, near Yakutat. Once we arrive, we need to calibrate the instruments used for collecting data and compare the results to the start of the trip. This will let the scientists know that their instruments are stable and making consistent measurements.

While calibrating we may have an opportunity to get a glimpse of the Hubbard Glacier at the head Yakutat Bay. The Hubbard Glacier is approximately 6 miles wide and when it calves, makes icebergs 3-4 stories tall. Fingers crossed we get to see it! 

On a side note, I have been drawing while on the boat. Here are some photos!

Jessica's sketch of a squid
One of the squids we caught… it was just a tiny little guy, about 2 cm.
Diagram of commercial fishing methods
Gus Beck, lead night fisherman, sat down with me yesterday and explained the main types of commercial fishing methods. Now I won’t get them mixed up.
Abigail's prowfish sketch
This is my favorite one! Abigail’s drawing of a prowl fish. They have the best facial expressions.


Science and Technology Log

The majority of my time has been spent above deck with the science and deck crews. Yesterday, I took the opportunity to head down below and learn some of the ways Oscar Dyson is kept running smoothly. 

Danielle and deck crew
Some of the deck crew that are responsible for putting the nets out. Danielle, one of our senior survey techs, is up top and controls the movement of the net.

There are several areas/rooms that hold different types of equipment below deck. One of the largest rooms is the engine room, where not 2 or 3, but 4 engines are located. At night, 2 of the engines are needed since the ship sails slowly for camera drops. During the day, when traveling along the transects and fishing, 3 engines are used. Engines 1 and 2 are larger with 12 cylinders and 3 and 4 are smaller with 8 cylinders. These engines are attached to generators. The engines give moving force to the generators, which they then convert into kilowatts/power and as a result, power everything on board. Also, I learned that the boat has at least 2 of every major piece of equipment, just in case!

Engineers Kyle and Evan
Two of the engineers, Kyle Mulkerin and Evan Brooks, who gave me a tour below deck. They are standing in front of engine #1.

The engine room also stores the water purification system, which Darin had mentioned to me the other day. He knew the ship converted seawater into potable water, but wasn’t exactly sure how the process worked. Here is a brief summary. 

  1. Seawater is pumped onto the boat and is boiled using heat from the engine.
  2. Seawater is evaporated and leaves behind brine, which gets pumped off of the ship.
  3. Water vapor moves through cooling lines and condenses into another tank producing fresh water. 
  4. The water is then run through a chemical bromide solution to filter out any left over unwanted particles.
  5. The finely filtered water is stored in potable water holding tanks.
  6. The last step before consumption is for the water to pass through a UV system that kills any remaining bacteria or harmful chemicals in the water.
Evan's notes
Notes from Evan Brooks on how to convert seawater into potable water. I wish all my student’s notes were this neat and organized!

After the engine room, Kyle and Evan took me one level deeper into the lower engine room. There are a few other lower areas but, being a bit claustrophobic, I was happy we didn’t explore those. The lower engine room (or shaft alley) holds the large rotating shaft which connects directly to the propeller and moves the ship. It was neat to see! 

Jessica descends to lower engine room
Heading down into the lower engine area.

We rounded out the tour in a workshop that holds most of the tools on board. The engineers help fix things from engines to air conditioners to plumbing. This week I may even be able to see them do some welding work. 

Did you know? 

If a large piece of equipment needs to be replaced, they do not take it apart and lug it to the upper deck and off the boat. Instead, they cut a giant hole in the side of the ship and get the parts in and out that way. I had no idea!

Cheers, Jess 

Catherine Fuller: Searching for Water in the Ocean, July 9, 2019

NOAA Teacher at Sea

Catherine Fuller

Aboard R/V Sikuliaq

June 29 – July 18, 2019


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

Geographic Area of Cruise: Northern Gulf of Alaska

Date: July 9, 2019

Weather Data from the Bridge

Latitude: 57° 47.549 N
Longitude: 147° 30.222
Wave Height: 0-1 with swell of 4 ft
Wind Speed: 1.7 knots
Wind Direction: 170 degrees
Visibility: 5 nm
Air Temperature:  13.1 °C
Barometric Pressure: 1014.4 mb
Sky: Overcast


Science and Technology Log

Ana’s Work: 

iron fish deployment
Dr. Aguilar-Islas oversees the iron fish deployment.
iron fish on deck
The “iron fish” on deck…
iron fish in water
..and in its habitat.

Dr. Ana Aguilar-Islas and her team of Annie, Kelsey, and Carrie are studying how the different sources of iron in the Gulf of Alaska influence its chemical structure.  Iron is considered a micronutrient, because it is a nutrient that is needed in lower quantities than silicate, phosphate and nitrate, which are macronutrients. Iron is essential for phytoplankton.  Iron does not easily remain dissolved in ocean water, but has a tendency to precipitate and become a particle.  It is essential for many functions within phytoplankton, including gene function and photosynthesis, so the presence or absence of iron in the water is an indicator of the viability of the ecosystem. 

Testing phytoplankton in both an iron-limited environment and an iron-rich one allows scientists to pinpoint the effect that iron has.  The water in the Gulf of Alaska is notable for having more iron, leading to larger zooplankton as compared to areas, such as Hawaii, where the lack of macronutrients in the water means that they’re much smaller.  The Copper River plume was an example of a naturally occurring source of iron although its decrease is exponential the farther you move from the plume. 

In order to test samples without any contamination from being in an iron ship, Ana’s team created a “bubble” room or a clean space to do testing.  Her samples come directly from the “iron fish,” a collection instrument that is towed along the starboard side of the ship, and a pump on deck sends water through a tube that is carefully strung from the “fish” through the hallways and into the “bubble.”  The team is testing water samples for dissolved iron, particulate iron, and ligands (naturally occurring structures that bind iron and allow it to stay dissolved in seawater).  Both the filtered (any plankton filtered out) and unfiltered samples that Ana’s team collects are also used by other teams to provide context for their own experiments, especially testing the behavior of phytoplankton populations in iron-rich and iron-poor water.

looking in the bubble
The bubble from the outside.
Annie at the bubble
Annie spends many hours patiently taking water samples in the bubble.


The Search for “Perfect” Water

After completing our comprehensive zig-zagging study through the Copper River plume, it was decided to continue on a path south to find HNLC (high nitrate low chlorophyll) water.  We’re specifically looking for water with a salinity over 32.4 psu and nitrates over 3 micromoles. Water like this would be low in iron.  Normally, the lack of iron is a factor that limits photosynthesis,.  However, in areas with these numbers, phytoplankton communities have evolved to survive in an iron-deprived environment. 

What Clay, Suzanne and Ana hope to do is to introduce both Copper River iron-rich water and commercially available iron into samples of these communities to see if a “bloom” or a sudden growth in population will occur.  It’s been a long search so far, taking us through an offshore eddy, watching salinity numbers slowly creep up as we leave the plume’s fresh water influence behind us.  To pass the time, my cribbage board came out and I’ve lost to Pete, Seth and Ana (although I beat Seth once).  To help Suzanne and Ana find their water, Seth stitched together a composite satellite picture of the chlorophyll in the Gulf from images taken over the last few weeks.  This showed an eddy south of the Copper River plume that provided a possible location for the right sampling of water.

Our initial target was 58 degrees N, 146 degrees W, however, we’re continuing on the journey south to see if we can find the right spot.  For a long time, we were towing the Acrobat behind us, trying to get additional readings, however, our speed with the Acrobat is limited to a maximum of 7 kts.  Early this morning, the Acrobat was pulled in and we’re now cruising at about 10 kts.  We’re supposed to move over to the GAK (Seward) line of waypoints after this, but the joke is that we’ll reach GAK 125, i.e. Honolulu, before we find water that fits the parameters we need.

After careful monitoring of our position and the information screens in the computer lab, it seems that our target water is between 57 degrees 21 minutes N between 145 degrees 42.8 minutes W and 145 degrees 39.9 W.  Finding the perfect water is complicated by the number of anomalies in the sea surface. We’re having the bridge go through specific maneuvers to take us back and forth through the target patch of water. As we move through what seems reasonable, Ana’s iron fish will be deployed to start bringing in  “perfect” water samples. 

Sea Surface Temperature Anomalies
These anomalies represent changes in sea surface temperature, and in turn in the chemical composition of the water. On the map, you can see the lines we’re surveying from left to right: Kodiak, Seward (GAK) and Middleton.
our course
Our zigzag course: the bridge asked if we were making course lines with an Etch-a-Sketch!

Since last night, there has been at least one person stationed in the computer lab with eyes on the underway data display to monitor the salinity and nitrate levels.  Today, with Dr. Strom, Clay and myself there, we jump every time the nitrate value does.  Once our target patch is isolated, Dr. Strom directs the bridge to zigzag the ship through it to find maximum nitrate values and then radios the iron fish team. It’s 2.1….it’s 2.7…quick! Collect samples!  It’s a crazy system, but for now it’s getting us the best results we can, considering the fluidity and changeability of the ocean. 

I’m not sure what the bridge thinks about our maneuvers, and we’re all imagining what they’re saying! They have been very patient and willing to go along with requests; they’re pretty used to the demands of scientists in search of specific answers.  We’re finding our highest values to be about 3.2 micromoles, and it seems that we’ve also narrowed down the “sweet spot.” In addition, a group of fin whales is moving through the area and is making regular appearances as we trace and retrace our path. At one point, Eric, the captain came down to chat and helpfully volunteered to look up the definition of “zig” and “zag” so that we would have our terminology correct.  Is zig the upward progression or the downward one?

Most of the science done on board is carefully planned and prepared for.  Methodologies are clean and precise in order to produce specific and incontestable results.  Sometimes, however, science requires taking advantage of the situation at hand to find optimum data.  Science can be messy and inexact, too, if the end result is finding the perfect drops of water in the ocean.


Personal Log

We are now over the 50% point in our trip.  It is a bit ironic that as the science team and the crew get to know each better and develop friendships, both sides are also looking ahead to the end of the trip.  It’s been fun to get to know the crew and to discover the personalities that make this ship run so smoothly. 

Our weather has been notably calm so far, with today’s nearly flat seas being the smoothest to date.  We have fog every day; every day the sea surface temperature is higher than the air temperature.  What might that be an indication of? Russ seems to think it’s a fairly unusual pattern.  Even though today’s temperature is in the mid-50s, the stillness and reflected light off the surface of the ocean almost make it seem warmer.  It looks like we can continue to expect fairly calm seas for the next few days, too.  Every day someone posts a weather forecast in the mess hall, and every day the forecast is similar.    

fog bank on the horizon
Seeing fog banks on the horizon is a daily occurrence.

We continue to eat remarkably well.  Today’s lunch was spaghetti or zoodles with eggplant parmigiana, shrimp, and hot veggies.  This week already, we’ve had pecan pies and oatmeal raisin cookies for dessert and apple and berry turnovers for breakfast.  The food is definitely one of the benefits of being on this ship!


Did You Know?

The fresh water measured in the Copper River plume equates to a quarter of the yearly excess melt from area glaciers.  The question then is, where does the other three-quarters go?


What do you want kids to know about your research?

Ana: There are nutrients in the water that sea creatures need: large nutrients and small ones.  The small ones are important because they’re needed more often, like vitamins being a more regular part of your diet than hamburgers.


Sea Creatures seen today:

fin whales
A small group of fin whales came near us several times during our zigzag maneuvers.

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: Don’t Forget the Phytoplankton! 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

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.

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.

Gavenus1Birds

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

Gavenus2Birds

Nesting tower on Middleton Island.

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

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

Scientists deploy CTD

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

CTD at sunset

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

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

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

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

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!