Ocean decline around Antarctica

A variety of human impacts threaten ocean ecosystems around Antarctica. The expected results? According to a new study, unless we change our path the Southern Ocean will face: simplification, homogenization, loss of uniqueness--the "dumbing down" of the ecosystem.

"Antarctica is the most isolated continent on Earth, but it has not escaped the negative impacts of human activity. The unique marine ecosystems of Antarctica and their endemic faunas are affected on local and regional scales by overharvesting, pollution, and the introduction of alien species. Global climate change is also having deleterious impacts: rising sea temperatures and ocean acidification already threaten benthic and pelagic food webs. The Antarctic Treaty System can address local- to regional-scale impacts, but it does not have purview over the global problems that impinge on Antarctica, such as emissions of greenhouse gases. Failure to address human impacts simultaneously at all scales will lead to the degradation of Antarctic marine ecosystems and the homogenization of their composition, structure, and processes with marine ecosystems elsewhere."

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Ross sea toothfish decline?

This is very bad. An Antarctic toothfish fishery with a controversial sustainability certification may be the cause of a substantial fish decline. In a charismatic place that scientists care about...a lot.

Toothfish seem to be disappearing from McMurdo Sound in the southern Ross Sea thanks to the eco-labelled Antarctic toothfish fishery. This from deliberate and methodical scientists, not finger-wagging enviro radicals.

If this proves true, it's hard to support the credibility of the Antarctic toothfish certification by the Marine Stewardship Council. And if you have doubts, you're in good company. A star-studded cast of scientists have weighed in with doubts about the sustainability of this fishery.

Toothfish are only one of the cases that fishyfellow is doggedly blogging about at "How Sustainable are Eco-Certified Fisheries?" Want to learn more about spiny dogfish certification? How about surveillance audits of South African hake? It's not the sexiest blog in the world, but it is meat and potatoes for anyone with a scientific bent who is concerned about ocean ecosystems.

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Killer crabs invade antarctic shallows

Warming water near Antarctica has big predatory crabs on the move, threatening soft animals that have been protected by the cold for millions of years.

King crabs die below 1 C, so the cold 0 C to -2 C Antarctic shallows were a safe home for sea lillies, brittle stars, giant ribbon worms and molluscs that are armoured only with thin, soft shells.

Since the 1950s, when records began, the average temperature of the ocean to the west of the Antarctic peninsula has gone up by 1ºC, and king crabs appear to be moving into shallower water. If this is true, climate change may soon claim a set of victims, the unprepared and under-protected soft animals used to being insulated from harm by the coldest ocean water.

Oh, for the sheltering cold.

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Shrimp on ice

What lives under Antarctic Ice? Scientists thought maybe nothing, except those silly little microbes that live everywhere. But guess what happens when you do an actual experiment, sometimes you find a big surprise.

Like the false bologna sandwich hypothesis, the now-discredited "nothing big lives under the ice" hypothesis is toast.

As soon as scientists placed cameras under the 600 foot thick Antarctic ice sheet at the bottom of a hole drilled through the ice, a cute little 3 inch long orange shrimp settled down on the camera cable and stared at them (photo at top left). Wondering, no doubt, how creatures can live outside of the nice comforting dark water that's always the same comforting temperature of 272 degrees Kelvin.

That's right folks, harsh is in the eyes of the beholder. An Antarctic shrimp must find it's own habitat to be quite nice, and a tropical beach in the Bahamas would be like being cooked in boiling water. It's all what you're used to.

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Elephant seals study ocean & climate change

Elephant seals are being recruited as expert scientists for doing research work where people can't go--deep in the ocean under sea ice in Antarctica.

"As the creatures dive and hunt in one of the most inaccessible environments on Earth, they are feeding back information that is helping to shed light on the climate, using sensors that have been stuck to their coats.

The transmitters, developed by St Andrews University, are glued to the elephant seals and effortlessly measure the physical properties of the ocean, until the mammals shed their coats and lose the small devices after about a year."

Elephant seals are well suited to the task, diving as deep as 2 km and ranging widely under sea ice in areas inaccessible to people. Sounds like the work deserves a PhD for the elephant seals, if they're willing to talk about their findings at a public seminar.

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The banana belt gets warmer

One of my favorite experiences in Antarctica was dive tending. Back when I was just a wide-eyed college phycologist, I spent a summer coring ice and running samples out of McMurdo station. Across the hall, two guys named Mark spent their days under the ice, picking up anything unusual and bringing it back to the lab to give it a name and grind it up. Rumor had it they even ate a few nudibranchs, in the name of science. While my samples were running through the various testing machines, I could take a couple of hours and head down to the edge of the ice with them, spooling out the rope that would lead them back up.

The job of the dive tender is not taxing. You must keep the rope taut, so it doesn't tangle on rocks or ice. If you see an orca nearby -- or worse, a leopard seal -- you give a series of short warning tugs. Leopard seals were particularly notorious for chomping divers. Otherwise, you let your lab-weary eyes take in the vast beauty of the Ross Sea, with tiny penguins picking their way across the ice. When the Marks return, their mesh bags contain sponges, corals, and other strange animals surprisingly brightly colored for life that never sees sunlight.

I'm reminded of this by an article in the current issue of American Scientist: Ecological responses to climate change on the Antarctic peninsula. Down in MacTown, we called the peninsula the "banana belt" for its relatively milder temperatures. Heck, they even have plants. Now, it seems the banana belt is getting even warmer, both in the sea and on land.
Dr. James McClintock (lead author and former advisor to one of the Marks) describes a world where salps supplant krill at the base of the food chain, and sponge-crushing crabs move into the invertebrate gardens. Even if you're not a regular sci-journal reader, check it out for the introduction and the illustrations.

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