Krill population decline from Wilkins Ice Shelf Collapse

[Matt Rogers]

Ice shelf collapse: What does it mean? - CNN.com

Interesting observation here about magnesium and inverts too.

(CNN) -- From krill to king crabs, the collapse of a 160-square-mile portion of the Wilkins Ice Shelf in Antarctica could mean many changes for wildlife at the bottom of the world.


Krill may not be the most exotic of creatures, but climate change could affect them like any other animal.


Most inhabitants of our planet will never get a firsthand look at a polar bear at the North Pole or a penguin at the South. But polar scientists already see changes in plants and animals from rapidly warming temperatures.

But there may be a non-global-warming explanation for the decrease. Once heavily hunted, humpback whales that feed on krill have made a comeback in Antarctic waters.

So it is also possible that more whales are simply eating more of these tiny crustaceans.

Another warming ocean event that scientists are studying closely is the migration of king crabs. Marine remotely operated vehicles have captured photos of these giant crabs on the Antarctic Slope, where underwater land starts to rise up to the southernmost continent.

It's the first time in tens of millions of years that these predators have appeared that close to Antarctica.

Crabs and other marine invertebrates die when the water is too cold, because they cannot flush magnesium out of their systems. But even slightly warmer seawater allows the animal to regulate that element.

McClintock says that if these new predators keep moving, they could wipe out other Antarctic species. Snails, brittle stars, sea spiders and some marine worms have evolved without armor and other protections they would need to survive alongside the king crab.

Scientists studying Adelie penguins on Antarctica's western peninsula see that species suffering major declines. Ironically, an increase in snowfall could be among the most dangerous "warming" effects for this animal.

"In Antarctica, as the air temperature warms up, the humidity rises and the ability of snowfall to occur increases," McClintock said.

[KOgle]

Interesting. Wonder how many animals we're going to see go extinct in our life times due to our careless-ness???