Friday, January 20, 2012

From Penguin Science: Promote the Penguin Population!


 Penguin Science | Losing the Last Pristine Marine Ecosystem on Earth
“Fortune favors the bold,” is how the saying goes and these days, having depleted fish elsewhere on Earth, the fishing industry has become so bold as to now be fishing the ice-covered waters of the Ross Sea.  The risk is high for vessel catastrophe, but so is the fortune.  They and their investors are making huge profits in those heretofore unfished waters, beginning with the take of Antarctic toothfish (marketed as Chilean sea bass) in large quantities.  Owing to the cost, only the rich can afford to eat these fish.  These fish are 50 years old and are very slow to grow and replace themselves; those taken now won’t be replaced even within two lifetimes of a typical commercial fisherman or fishing vessel.
Antarctic toothfish are likely the most important upper-food-web predator in the Ross Sea, and a huge body of research recently coming to fore shows that removing such fish from marine ecosystems elsewhere has had grave repercussions for the system. Following depletion of top predators from marine ecosystems, negative results include invasions of jellyfish, appearance and increased prevalence of toxic plankton blooms with accompanying fish-bird-mammal die-offs, and dramatically increased sensitivity to climate change.
Heretofore — though time is rapidly running out — the Ross Sea remains the last open-ocean marine ecosystem on Earth free of alien species, of large-scale pollution and minerals development, and of toxic plankton blooms and anoxic (oxygen depleted) events.  It is the only continental shelf ecosystem remaining on Earth that has its full complement of whales, seals, seabirds, large fish and shell-fish. Unlike elsewhere, it still operates as it did when humans were just beginning to appear on Earth. It therefore has huge heritage value and incomparable value as a resource through which to understand, through art and science, how all continental shelf marine ecosystems once functioned.

If you want to better understand what will be lost as exploitation proceeds in the Ross Sea, read Daniel Pauly and Jay Macleans’s now classic book In a Perfect Ocean: The State ofFisheries and Ecosystems in the North Atlantic Ocean (Washington DC: Island Press).  They describe what the North Atlantic once was like, hundreds of years ago, and therefore how the Ross Sea is now:  whales so numerous they impeded vessel traffic, fish the size of a man as numerous as snow flakes, and shellfish so numerous that in a matter of days they filtered entirely the waters of places like Chesapeake Bay. Although just 15% of the Antarctic circumference, the Ross Sea contains approximately:
  • 1,880,000 breeding Adélie Penguins, 38% of the World population;
  • 104,000 breeding Emperor Penguins, 26% of the World population;
  • 6,000,000 Antarctic Petrels, >30% of the World population;
  • 71,000 Antarctic Minke Whales, ~21% of World population;
  • 3,500 killer whales, an unknown proportion of the World population;
  • 32,000 Weddell Seals, 45% of the Southern Ocean Pacific sector population;
  • 205,000 Crabeater seals, 12% of the Southern Ocean Pacific sector population;
  • 6,000 Leopard seals, 11% of the Southern Ocean Pacific sector population.
    It should be a World Heritage Site.

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