Gregory Cook, The Marinovich Trawl, July 29, 2014

NOAA Teacher at Sea

Gregory Cook

Aboard NOAA Ship Oscar Dyson

July 26 – August 13, 2014

Mission: Annual Walleye Pollock Survey

Geographical Area: Bering Sea

Date: July 29, 2014

Science and Technology Log

It’s 4 in the morning. I make my way into the cave. The cave is the computer lab. On one wall the size of my classroom whiteboard, there are nine computer monitors, each one regularly updating with information about the fish under the boat. We’ll talk more about the tech on another day. Today is my first trawl. A trawl is when we drop a net and haul up whatever we can catch.

I’m still getting my head around a cup of coffee when Alyssa comes in wearing a hard hat and life vest.
“In about 20 minutes, I’m going to need another hand on deck wearing this.” She points to her gear.
I nod. “Where do I find that?”

Alyssa politely tells me where the gear is. I remember that I’m not supposed to go out on deck when they’re hauling up the net… at least not yet. “Who do you want me to tell?” I say.

“Nate would be great! Nate or Darin!” she says, referring to a pair of scientists… one of whom is going off duty (and probably going to sleep) and another who is coming on (and likely just waking up). She grabs some large tool that I can’t name and heads off. Alyssa, like a lot of the crew, is friendly and upbeat in the mess hall (the cafeteria), but is completely focused and efficient on the job, with an eye towards safety and getting the job done.

Our first trawl is the Marinovich Net. It’s a smaller net, but still takes several fishermen and a winch to bring up. It’s a fairly fine net, with holes about the size of a ping pong ball. In our first trawl of the trip, we mostly catch jellyfish. These aren’t your typical, East Coast jellies, though. Some of them are the size of basketballs, and you can see the fish THEY’VE caught through their see-through membrane (their skin!).

We ended up hauling in over 500 pounds of Jellyfish!

It’s not a bad first catch, but NOAA scientists aren’t content with that. Hanging on the side of the Marinovich are smaller “pocket” nets. This is where we find out what the Marinovich missed. Nate explains to me that, while we are mainly studying Pollock, there’s other valuable data that can be gleaned (collected) in the process. Other scientists studying Krill populations will be grateful for the data.

The pocket nets are labeled, and each net is placed in a labeled bucket. Then I grab a pair of tweezers and start sorting. It’s mostly krill… skinny shrimp-like organisms with beady black eyes. These tiny invertebrates, altogether, make up millions of metric tons of biomass, according to Misha, our resident Russian scientist on board. Biomass is the amount, by weight, of living things in an ecosystem.

Nate asks me to count out 100 krill with my tweezers, which is kind of like counting out 100 tiny pieces of wet spaghetti. Nate places the 100 on a scale and comes up with a mass of 5 grams. He then measures the rest of the krill, and uses the mass of the original 100 as a way to gauge the total number of krill caught in the pocket net.

What stands out to me about this whole process is the attention to detail. That each pocket is carefully sorted, measured, and entered into a computer base. There’s no “-ish” here. I’m not asked to sort “about a hundred.” Not only are the contents of each pocket net measured, but we make sure to note which pocket had exactly how much.
Some of the catch isn’t Krill, however. Sandi calls me over to see how she measures a tiny rock fish. Sandi is a marine biologist who studies reproduction in Pollock. With a gleam in her eyes she explains what’s so great about getting different size young in the net.

“What it means is that it’s possible that some of these fish might be from further away… and we don’t know how they got here, when they got here, or where they came from. And that’s exciting! We weren’t expecting that and it gives us a whole new set of questions!”

I get asked by a lot of kids “how do scientists know that?” My long answer is exactly this. That good scientists DO sweat the small stuff, they make sure that every little variable is accounted for, and collect massive amounts of data. They look for any possible error that might throw off their results or call their conclusions into question. They do the hard work of truly understanding.

So when I hear folks say they don’t believe something simply because it’s inconvenient for them… maybe it challenges a belief that they’ve clung to for no better reason than not wanting to be wrong… I just want to say “Did you do the work? Because I know some people who did.”
And this holds true for all the scientists I’ve been lucky enough to know. Whether they were counting krill, measuring background radiation, or looking for Dark Matter.

By the way, my short answer on “How do scientists know that?” They did their homework.;)

Personal Log

It’s the morning of our third day at sea. It’s taken some getting used to… the first piece is the motion of the boat. Any 8th graders that went on “Untamed!” with me at Canobie Lake Park know that I’ve got some limits as to how I handle a lot of “movement.” The first 8 hours onboard the Oscar Dyson were rough. I thought I might get sick at any moment! But over time, the body figures it out… It’s like your body just says “Oh, this is just what we’re doing now…” and gets OK with it. Now going to bed is like being rocked to sleep by mother earth. 🙂

The next, very different thing about life on the Bering Sea is time. My schedule is from 4 a.m. to 4 p.m… which in some ways is good. 4 a.m. in Alaska is 8 a.m. Eastern Time (Boston Time). So coming home won’t be that tough. The weird thing is going to sleep. This is the view out my window at 11:00 at night.

This is, of course, because the earth has that big old tilt of 23.4 degrees. This is why Alaska is known as “The Land of the Midnight Sun.” Well, we’re a little more than a month past the summer solstice, and we’re not currently above the Arctic Circle. So the sun DOES eventually go down… around Midnight! That means that I need to go to sleep during the daylight. Sometimes as early as 8 p.m.! And that means I need a lot of shades… Shades for my window, shades for my bed, even shades for my head!

We live in an amazing time, where we can travel about the planet, see the extremes that are possible under the physics of this world, and communicate that experience in the same day. Tune in next time when I tell you how to tell the gender of a Pollock. Hint: You can’t just lift their tail!