Well, it was a successful fishing trip. I think we caught over 51 fish. Unfortunately, though, one of our rock cod species, Notothenia coriiceps, ate some of the other fish in its tank, making our total count shrink. When we were transporting and opened the tank that was mixed with coriiceps and gibi, we saw a lot of red fleshy bits floating in the water with a decrease in biomass of gibi. In science when we euthanize our fish we call it "processing." Looks like coriiceps did the processing already for us.
The seas were really calm, and we had beautiful weather. It made for an extremely peaceful voyage. Around 3 P.M. on Friday we set the pots/traps at Dallmann Bay. We steamed our way to Low Island, and we began dropping the nets at around 10 P.M. The marine techs on board were actually the ones to drop the nets. We just stood back and observed; our job was to collect and sort the fish. It takes about 15 minutes for the net to go down, 20 minutes for trawling, and another 10-15 minutes to bring it back up. I stayed up until about 4:30 A.M. to help collect and sort the fish, but then at that time Dr. Detrich joined us. Since the other two members in my group decided they want to stay up all night, I chose to go to bed. We didn't need four people digging through the nets to find our fish. In fact, we really didn't need three either. Anyway, the nets came up a lot more different from what I expected. When they come up and hit the deck, we open them up and begin digging. The nets just drag and collect everything that's on the ocean floor, including seaweed, starfish, small octopuses, smaller fish, and many very strange looking Antarctic species. Of course, we also get our fish. Each trawl that night was catching close to 10 fish. We actually started running out of room in our tanks so we ended up doing dissections. I was asleep for those unfortunately.
The next day on Saturday, we made our way back to Dallmann Bay to recover our traps. We had some other people on the ship assist us with coiling the ropes so that my research team could focus on getting the fish (coriiceps in this case; aceratus and other ice fish were in the trawls) and transporting them to the temporary tanks. We also had to remove the bait bags (filled with chopped up herring and we threw a rotten orange in a few of them to see if they'd attract more fish) and break down the traps. All in all, we managed to obtain over twenty coriiceps.
Since we didn't really have more room in our temporary tanks, we chose not to go trawling again last night. This meant that I got to sleep at a regular time :)! We arrived on station at about 8:30 A.M., and soon after the crane on the ship began offloading our tanks. From there, we took each fish out of the tanks individually, dipping them in a special bath (diluted VidaLife) that repairs their mucous layer as well as injecting them with hormones (OvaPrim) to finalize their sexual development. Some of our aceratus females have orange bellies because they're swollen with eggs. We still need to advance their development a bit to make sure that they're ready to actually spawn the eggs. I guess you could say that the Easter bunny visited us yesterday, if you catch my drift.
All in all, we have close to or above 80 fish in our tanks. Unfortunately for gibi and some of the smaller aceratus fish, they're all going to be killed today and tomorrow for dissections and tissue sampling. We'll be keeping coriiceps and aceratus for breeding purposes. Hopefully we got some males in the group. The males are significantly smaller than the females, so it's hard to tell if we just have a bunch of juvenile females or if they're actually reproductively developed males.
Now I'm just doing some laundry and typing this up. Soon I'll try to join Yinan and Urjeet downstairs to do some dissections. They said that they don't need my help, but it would be nice if they could save me a fish or two. If not, then I suppose I could always go back to reading. I both started and finished Oscar Wilde's play The Importance of Being Earnest (which was hilarious if I may add) while on the ship waiting to trawl in the night. In the lounge we have walls filled with books, so it shouldn't be difficult to find something else to read.
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