Edge of the Arctic Shelf

El Copepodito
They call him "El Copepodito" (little copepod). His real name is Leopoldo Llinas, and his mission on this cruise is to collect tiny marine animals called copepods, which are a type of zooplankton. Leo is a graduate student at the Rosenstiel School of Marine and Atmospheric Science in Miami, Florida. He is studying the distribution and abundance of copepods and other zooplankton in the Western Arctic Ocean. Specifically, he is interested in the advection (movement) of large-bodied copepods from the Bering Sea and Canada Basin onto the Chukchi and Beaufort shelves.

Leopoldo is using a device called a MultiNet to catch the zooplankton. As the name indicates, several different nets are all connected to the same frame. The MultiNet allows Leopoldo to collect plants and animals from different levels of the water column, since different species live in different water masses at different depths. When the cod ends (collection jars) are brought onboard, he examines the copepods under a microscope and then preserves the animals in ethanol for future molecular analysis or in formalin for counting.

Has anything you have collected so far surprised you?
"I was surprised by what I found on the Beaufort Slope, near the WHOI moorings. In the upper levels of the water column, I caught a very large amount of tiny marine plants called phytoplankton. It was very thick, like pea soup."

We have received a great question from Benito in Torrejňn de Ardoz, Spain.
How do you feel when you are not able to recover an instrument, such as the arctic winch?

Since the arctic winch is one of Bob Pickart's instruments, I asked him to reply to this question:
"That's an excellent question. To answer it I have to give you a bit of background. One of the challenging aspects about putting moored instruments in the Arctic is the danger from ice ridging. When pack ice collides and deforms you can often get deep ice "keels", i.e. a region where the ice extends far down into the water. In our working area it is not unheard of to have ice keels extend 30-35m below the surface. Hence, we made sure not to have the top portion of our moorings extend any shallower than this. The downside of this, however, is that we miss out on some interesting science. So last year I decided to try an experiment whereby we attach a buoyant float to the top of one of our moorings in order to sample this remaining part of the water column. The float contained scientific sensors and was connected to a spool of line. Twice a day the spool would release and the float would rise to the sea surface---or the bottom of the ice---then winch itself back down to the mooring (hence the term "Arctic Winch"). I was extremely excited about the prospect of measuring this part of the upper Arctic, as were the engineers who built the device, but at the same time we knew it was risky. So it was with considerable disappointment that we discovered the Arctic winch was missing. I don't know if it got stuck in the ice, but we will at least have a record of when it broke by examining the engineering data in the motor of the winch. We also learned a lesson: the next generation of the instrument will have the ability to transfer its scientific data to the mooring after each round trip. This way, if the float breaks, we will at least have the information up to that point. As a final note, I would like to say that I believe in pushing the boundaries in order to learn new things in the field, and consequently I have taken risks throughout my career. Not all of them have worked out, but when they do it is extremely exciting and rewarding---and brings us a little closer to figuring out some of the mysteries of the ocean."