Ragupathy Kannan: Starting with Plankton, August 18, 2019

NOAA Teacher at Sea

Ragupathy Kannan

Aboard NOAA Ship Gordon Gunter

August 15-30, 2019


Mission: Summer Ecosystem Monitoring

Geographic Area of Cruise: Northeast Atlantic Ocean

Date: August 18, 2019

Weather Data from the Bridge

Latitude: 38.2494289
Longitude: -75.0853552
Water temperature: 26.3°C
Wind Speed: 4.92 knots
Wind Direction: 122 degrees
Air temperature: 27.1°C
Atmospheric pressure: 1015 millibars
Sky: Partly cloudy


Science and Technology Log

In my previous blog posting, I explained the importance of plankton as base of the ecological pyramid upon which much of marine life in this ecosystem depends.  The past few days, I have witnessed and experienced in-person how scientists aboard this sophisticated research vessel collect and analyze sea water samples for plankton. 

Yesterday I spent some time with Kyle Turner, a guest researcher from the University of Rhode Island doing his M.S. in Oceanography.  He operates a highly sophisticated device called the Imaging FlowCytobot (IFCB).  I was fascinated to learn how it works.  It is basically a microscope and camera hooked up to the ship’s water intake system.  As the waters pass through the system, laser beams capture images of tiny particles, mostly phytoplankton (tiny photosynthetic drifters).  As particles do, they scatter the light or even fluoresce (meaning, they emit their own light).  Based on this, the computer “zooms in” on the plankton automatically and activates the camera into taking photographs of each of them!  I was amazed at the precision and quality of the images, taken continuously as it pipes in the water from below.  Kyle says this helps them monitor quality and quantity of plankton on a continual basis. 

Kyle Turner and IFCB
Kyle Turner with the Imaging FlowCytobot (IFCB)
Kannan and IFCB
Here I am examining a filamentous (hair-like) phytoplankton in the IFCB monitor.
IFCB computer screen
The various kinds of phytoplankton are neatly displayed on the IFCB’s computer screen. See my previous blog for a photo of the dazzling and colorful array of plankton out there! Plankton may lack the popularity of the more charismatic sea animals like whales, but much of life in the ocean hinges on their welfare.


Career Corner

Hello, students (especially bio majors).  In this corner of my blogs, I will interview some key research personnel on the ship to highlight careers.  Please learn and be inspired from these folks.

Here is my interview with Kyle Turner.

Q. Tell us something about your graduate program.

A. My research focuses on phytoplankton using bio-optical methods. Basically, how changes in light can tell us about phytoplankton in the water.

Q. How does this IFCB device help you?

A. It gives me real time information on the different types of phytoplankton in the location where we are.  We can monitor changes in their composition, like the dominant species, etc.

Q. Why are phytoplankton so important?

A. They are like trees on land. They produce about half the oxygen in the atmosphere, so they’re super important to all life on earth. They are also the base of the marine food web.  The larger zooplankton eat them, and they in turn are eaten by fish, and so on all the way to the big whales.  They all rely on each other in this big ocean ecosystem.

Q. How are phytoplankton changing?

A. The oceans are warming, so we’re observing shifts in their composition.

Q. What brought you into marine science?

A. I grew up on the coast.  I’ve always liked the ocean. I love science.  So I combined my passions.

Q. What is your advice to my students exploring a career in marine science?

A. Looking for outside research opportunities is important.  There are so many opportunities from organizations like NASA, NSF, and NOAA.  I did two summer research internships as an undergrad.  First was with NASA when I was a junior.  I applied through their website.  That was a big stepping stone for me. A couple of years later, I did another summer project with a researcher who is now my advisor in graduate school.  That’s how I met her.

Q. What are your future plans?

A. I’d love to get into satellite oceanography to observe plankton and work for NASA or NOAA.


Personal Log

I am pleasantly surprised by how comfortable this ship is.  I was expecting something more Spartan.  I have my own spacious room with ample work and storage space, a comfortable bed, TV (which I don’t have time for!), and even a small fridge and my own sink. Being gently rocked to sleep by the ship is an added perk! 

My own cozy stateroom
My own cozy stateroom
Sunrise view
A room with a view—sunrise from my window

The food is awesome.  We have two expert cooks on board, Margaret and Bronley. 

lunch
My first lunch on board
mess
The ship’s mess is a nice place to eat and interact with people. There’s always food available 24/7, even outside of meal hours.


Did You Know?

NOAA Ship Gordon Gunter played a big role in recovery operations following Hurricane Katrina and the Deepwater Horizon oil spill. 

Barograph
This photo is displayed in the galley. Note the sharp decline in atmospheric pressure as Katrina thundered through.


Some interesting animals seen so far

  • Flying fish (they get spooked by the ship, take off and fly several yards low across the water!)
  • Cow-nosed Rays (see photo and caption below)
  • Leather-backed Sea-turtle (I’m used to seeing them on the beach in Trinidad—see my previous blog.  It was a treat to see one swimming close by.  I was even able to see the pink translucent spot on the head).
  • Bottle-nosed Dolphins
  • Seabirds (lots of them…. four lifers already—more on this later!)
school of cow-nose rays
We saw large schools of Cow-nosed Rays closer to the coast. These animals feed on bivalve mollusks like clams and oysters with their robust jaws adapted for such hard food. They are classified as Near Threatened due to their reliance on oyster beds which are themselves threatened by pollution and over exploitation.

Andrea Schmuttermair: Tows Away! June 26, 2012

NOAA Teacher at Sea
Andrea Schmuttermair
Aboard NOAA Ship Oregon II
June 22 – July 3

Mission: Groundfish Survey
Geographical area of cruise: Gulf of Mexico
Date: June 26, 2012 

Ship  Data from the Bridge:
Latitude:  2805.26N
Longitude: 9234.19W
Speed:  10mph
Wind Speed:  5.86 knots
Wind Direction:   E/SE
Surface Water Salinity:  35.867 PPT
Air Temperature:  28.8 C
Relative Humidity: 86%
Barometric Pressure:  1010.51 mb
Water Depth:  96.5 m

Science and Technology Log


Sunrise

Sunrise on the Oregon II

Opisthonema oglinum, Lagadon rhomboides, Chloroscombus chrysurus…..yes, I have officially started dreaming about taxonomic names of our fish. It’s day 4 and I now have a much better grasp at identifying the variety of critters we pull up in our trawls. I am always excited to be out on deck when they bring up the trawl to see what interesting critters we catch. Surprises are great!

Do you want to know where the Oregon II is headed?

Check out Ship Tracker at http://shiptracker.noaa.gov/

If you click on the link above, you can see the path that our ship is taking to hit all of our stations for the survey. We often have station after station to hit- meaning as soon as we are done sorting and measuring, we have to bring in the next catch. Because some stations are only 3-5 miles apart, we sometimes have to do “double dips”, where we put in the trawl for 30 minutes, pull it up, and put it right back in again.

It’s been interesting to note the variety of our catches. Croakers, bumperfish, and shrimp have been in high abundance the last 2 days as we were in shallower water. Before that we had a couple of catches that had a high abundance of pinfish. When we take our subsample, we typically enter data for up to 20 of that particular species. We take length measurements on each fish, and on every fifth fish. We will also weigh and sex it (if sexing is possible).

Shrimp in the Gulf

A comparison of the various sizes of shrimp we pull up from our trawls.

Shrimp waiting to be measures

A relatively small catch in comparison to the 200+ we’ve been pulling up recently.

When we were in shallower waters, we had a significant increase in the number of shrimp we brought up. Tuesday morning was the first catch that did not have well over 200 shrimp (this is because we’ve been moving into deeper waters).  For the 3 commercial shrimp, white (farfantepenaeus setiferus), pink (farfantepenaeus duorarum), and brown (farfantepenaeus aztecus), we take 200 samples, as opposed to our high-quantity fish, where we will only take 20 samples. For each of the commercial shrimp we catch, we measure, weigh and sex each shrimp. I’ve gotten very good at identifying the sex of shrimp- some of the fish are much more difficult to tell. The information we get from this survey will determine the amount of shrimp that boats can take during the shrimping season in Louisiana and Mississippi. During the first leg of the groundfish survey, the data collected determined the amount of shrimp that could be caught in Texas. The groundfish survey is crucial for the shrimping industry and for ensuring that shrimp are not overfished.

Students- think of the food chain. What would happen if we overfished and took out too many shrimp? (Hint: Think of predators and prey.)

Sunrise

The trawl net at sunrise

We’ve now started doing 2 different tows  in addition to our trawls. Some of the stations are trawl stations, whereas others are plankton stations.

The trawl on deck

Alex, Alonzo and Reggie unloading the trawl net.

At a trawl station, we lower the trawl from the stern down to the ocean floor. The trawl net is meant for catching larger critters that live at the bottom of the ocean. There is a chain, also known as a “tickler”, which moves lightly across the ocean floor to lure fish to leave their hiding spots and swim into our net. The trawl is down for 30 minutes, after which it is brought back on deck to weigh the total catch, and then brought back into the wet lab for sorting.

Another important mission of the groundfish survey is to collect plankton samples. To do this, we use a Neuston tow and a bongo tow.

neuston tow

The Neuston tow about to pick up a lot of Sargassum- oh no!

The Neuston tow has a large, rectangular frame with a fine mesh net attached to it. At the end of the net is a large cylindrical bucket, called a codend, with a mesh screen meant for catching the organisms. In comparison to the trawl net, which has openings of 41.4mm , the Neuston’s mesh is only 0.947mm. This means the mesh is significantly finer, meant for catching some of the smaller critters and plankton that would otherwise escape the trawl net. The Neuston tow is put on the surface of the water and towed for 10 minutes. Half the tow is in the water while half is out. We end up picking up a lot of Sargassum, or, seaweed, that is found floating at the water’s surface. When we gather a lot of Sargassum, we have to sift through it and spray it to get out any of the organisms that like to hide in their protective paradise.

Bongo tow

The bongo tow on deck waiting to be sent down to about 3m from the ocean floor.

After we’ve completed the Neuston tow, we do the bongo tow.  The bongo’s mesh is even finer than the Neuston tow’s mesh at only 0.333mm. The bongo has 2 parts- a left and a right bongo (and yes they do look a little like bongo drums- hence their name). The top part of the bongo is a large cylinder with an open bottom and top. The net is attached to this cylinder, and again at the bottom of each side is cylindrical tube  called codends meant to catch the plankton. The bongo tow is meant to take a sample from the entire water column. This means that instead of riding on the surface of the water, it gets sent down to about 3 meters from the ocean floor (there is a sensor at the top that is 2m from the bottom of the net)  and brought back up immediately.

Sifting through the sieve

The remnants from our Neuston tow. This is the sieve we use to weed out what we want and don’t want.

bongo leftover

Here are our 2 samples from the bongo tow. The left one is preserved in ethanol and the right is preserved in formaldehyde (10% formalin and sea water)

Neuston tow samples

Here is a sample from the Neuston tow. Carefully camouflaged are thousands of crab megalops, aka juvenille crabs.

For both tows, it is important to rinse the nets to get any lasting organisms we might not see with our own eyes into our sample. Once we’ve done this, we bring the tubes back into the wet lab where we continue to rinse them through a sieve so that only certain items are leftover. In the Neuston, we often find small fish (usually less than 3mm), baby shrimp, crabs and Jessica’s favorite, the Sargassum fish. Most recently a few flying fish got caught in our Neuston tow. Prior to pulling it up, I was enjoying watching them flit across the water- they were about all we could see in the water in the middle of the night. After being rinsed thoroughly through the sieve, we preserve them by placing the sample in a glass jar with either ethanol or formaldehyde solutions. They are preserved in ethanol for DNA work and in formaldehyde for long-term preservation. These samples are then saved to send to a lab in Poland, which is the sorting center for the SEAMAP samples.

Flying fish

Flying fish we pulled up in our Neuston tow at nighttime.

Personal Log

My stateroom

My sleeping quarters (top bunk), also known as a stateroom. My roommate is Kristin, one of the scientists on board.

Well, I think I am finally getting used to the schedule of working the night shift. I am thankful that my bunk is on the bottom floor of the ship- which means it is completely dark- so that I can sleep during the daytime. Yesterday was probably one of the least busy days we’ve had so far, and because we were in deeper waters, our trawls were much smaller. This means I had a little more time to work on my blogs, which at times can be hard to fit in. It amazes me that we have internet access on the ship, and it’s not even as slow as I expected. It goes down from time to time, especially when the waters are rough. We’ve been fortunate to have pretty calm waters, aside from the first day.

You may have heard about Hurricane Debby on the news as it prepared to hit the Gulf. On Sunday, we were heavily debating heading back to Galveston to “bunker down” and ride out the storm. However, the storm that was forming seemed to dissipate and head in a different direction, thank goodness.  I was not thrilled about the possibility of heading back to port!

We had our first drills the day after we set sail. The drills- fire and abandon ship are distinguished by different types of bells, similar to using Morse code. The abandon ship drill was fun. We got to put on our survival suit, which is like a big orange Gumby suit. It not only protects you in cold water, but also makes you highly visible. I remember reading some of the former TAS blogs, and this picture was always in. Of course, I’ve got to add mine as well.

Survival Suit

Here I am in my survival suit. Judd also decided to be in the picture. 🙂

I’ve been having fun exploring different areas of the ship, even though there is only so far you can go on the ship. Yesterday, I went up to the bridge, which is the front of the ship where the captain or the NOAA Corps officers steer the ship from. You can think of it like a control center of an airplane. There are navigation charts (both computerized and paper) and radars that help guide the ship so it knows what obstacles are out there. There is a great view from the bridge that you don’t get anywhere else on the ship. It’s also fun to watch the folks down on deck when they are deploying the CTD or either of the 2 tows.

We’ve caught such an abundance of critters, I thought I’d share some of my favorite catches thus far:

cownose ray

Here I am holding a cownose ray (Rhinoptera bonasus)- my favorite catch yet. He weighed about 25lbs! This one was the highlight of my day as rays are some of my favorite ocean critters!

Atlantic sharpnose shark

One of the 4 Atlantic sharpnose sharks (Rhizoprionodon terraenovae) we’ve caught so far.

Sharksucker
A sharksucker (Echeneis naucrates)- these guys hang onto sharks to catch a ride- he’s still alive so is able to hang onto my arm!

Critter Query Time!

Critter Query #1: What is a fathom (in your own words please)?

Critter Query #2: What are the differences between skates and rays?