southern ocean islands Flashcards
what was the opening of the drake passage and tasman seaway?
development of westerly winds - wind-driven Antarctic Circumpolar Current
what are diatoms needed for?
Diatoms: abundant large phytoplankton fuels food chain and evolution of krill
how do baleen whales feel ecology?
their teeth filter water out. filter feeding. they expand ventral pouch and mouth, ajar to affect filtration.
what is the evolution of baleen whales in tandem with?
development of ACC
what does HNLC stand for?
high nutrient low chlorophyll
what are the different sides of south georgia like?
SW permanently galciated. NE ice-free
what is the Fohn effect?
Occurs with strong air flow over topography = Importance of latent heat (of condensation) = Can generate sudden T increase e.g. 8 -11ºC in alpine valleys –known as Föhnin Europe
what lives on the NE side of Georgia?
massive pengiun colonies. Albatross, giant petrel.
what is being campaigned in southern ocean islands?
o eradicate rats. restore populations of ground nesting birds.
where did Shackleton go?
24 April 1916, Ernest Shackleton, Endurance skipper Frank Worsley & four crew set sail set sail from Elephant Island in seven-metre lifeboat James Caird To reach South Georgia. ……. the 1500 km journey took 17 days.
why is longline fishing used in south georiga?
misses the big animals. solituion to predation. Patagonian toothfish.
The main line has heavy anchor weights at each end, and each branch line containing the hooks and cachalotera also have weights attached and therefore sink quickly, preventing seabirds from accessing baited hooks during setting.
During hauling, the cachalotera sleeve slides down the branch line to cover the hooks as they are hauled to the surface. This prevents seabirds and marine mammals, including whales, from being able to access the hooks during hauling
