Last night we crossed over a ridge into the Georgia Basin. This means that we are now downstream of South Georgia. This has two main impacts on the biology. Firstly, iron from South Georgia and/or the shelf surrounding it fertilises the water and causes a very strong phytoplankton bloom, concentrations being several times levels found further south. This captures a large amount of carbon dioxide out of the atmosphere and probably exports it to deep waters. This takes it out of contact with the atmosphere for several hundred years. I say probably as we we will recover the sediment trap tomorrow, but we (Southampton/PhD hat on temporarily) have shown this around the Crozet Islands. The second effect is we've got Krill back. We spent all night trying to catch them, but without success - very frustrating. Also means cetacean numbers are up - 6 Humpbacks and 6 Southern Right Whales this morning, and 5 Hourglass Dolphins.
A feeding group of Southern Right Whales
Bird numbers are also up and we had a new game during the last CTD cast of reading the code on a plastic ring on the leg of one of the birds. I eventually got it through binoculars and Jose confirmed with an excellent photo. Will be interesting to hear about the bird, it is presumably from Bird Island, a BAS base on a small island at the western end of South Georgia where birds and seals are studied.
ps to Elaine (and maybe others) I am starting to get some photos of inside the ship and will post them soon.
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2 comments:
Sorry but I have a mental image of people sitting on the back of the boat with fishing rods fishing for krill! :-)
Still I'm glad the cetaceans are back - some awesome photos. I also love the prion in the previous blog, they are such beautiful elegant birds.
I'm glad the weather is better too - I'm not sure I'd love the boat pitching and rolling like that, I managed to fall off and over enough things when it was rough in the Red Sea!
I'll be watching for those photos, Hugh. Thanks!
I don't know if you can do much downloading on ship, but if free books read aloud as mp3s are of interest (after a long day of salt spray and ice-blindness), take a browse through the LibriVox catalog, and be read to sleep.
http://librivox.org/newcatalog/visitor_advanced.php
Shackleton's "South!" has been done, as well as "Moby Dick" - by very good readers. I'm just saying... 8^)
Elaine
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