Thursday, July 28, 2011

Arctic Update 3 – Sharks!

The Amunsden sent over a mechanic to fix the hydraulics – so no deploying the CTD by hand (we did seriously consider it). Our day of trawling with the icebreaker resulted in no fish. I don't know if that means their experiment failed or not. The scientists on board invited us over for dinner, then slept through the meal – so no boat came for us. Eventually, we got hungry and cooked up our own dinner. We were three scientists working together to cook instant rice and we failed. I didn't realize it is possible to screw up instant rice! We screwed up scallops too.

26 July 11, we went back to pull up the line of hooks we set out two days earlier (we didn't intend to leave the line in the water so long, but, we couldn't pull it up without hydraulics). Most the hooks were gone, we assumed fish took the bait, then shark took the fish. We caught a female greenland shark that was 3.5m – big, however, the largest of these sharks reach 7m (or more, according to Pat, a fisherman from Newfoundland who is one of the crew).

These aren't scary sharks, in fact they are the slowest swimming fish out there. They range from here, Baffin Island, to off the coast of Norway and quite a distance south, off the coast of Georgia at over 2000m in depth. We don't know if they go further, in fact, there is a lot we don't know about these sharks. Greenland sharks aren't as sleek as tropical ones. Their skin is blotchy gray – smooth in one direction and rough the other way (true of all sharks). Their fins are quite rounded. They have a thick layer to protect them from the cold It's not fat – something else like a collagen layer, whale sharks also have this. Most of them have a parasite hanging off their eyes rendering them essentially blind. Since, they hang out so deep, being blind is probably not a hindrance.

In the morning of 27 July 11, we brought up another shark line, this time there was 13 sharks. Four had been munched on and were dead, as we brought them up to the surface to cut them free, northern fulmars (a sea bird with a head like a pigeon's) darted in for whatever scraps they could get. The ship was soon surrounded by these birds as they squabbled for the best spot. It took all day to tag the nine healthy sharks, all of them 2.5m and bigger. As soon as the fishing lines were in, I got my fourth CTD cast done.

Late last night we arrived back in Pangurtung to refuel. The wind is expected to pickup, so, we may not be able to get back to work for a few days.

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