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While the plight of the polar bear may be better known, emperor penguins are also going to be hit hard by the effects of global warming. Made famous by the documentary March of the Penguins, these flightless birds use the Antarctic's sea ice as a breeding ground and base for feeding on krill, fish and squid. But projected changes in Antarctic sea ice due to global warming will dramatically change the environment for these penguins and countless other species. Indeed, a 2008 study by a number of leading penguin experts warned that "50% of Emperor colonies ... and 75% of Adelie colonies ... that currently exist at latitudes north of 70 degrees S are in jeopardy of marked decline or disappearance, largely because of severe decreases in pack-ice coverage."
Making matters worse, these penguins increasingly must compete with man for their principal food: a small, yet invaluable shrimp-like animal known as Antarctic krill. Measuring only five to six centimetres in size, krill comprise the largest biomass in the Southern Ocean. These tiny creatures, rich in the omega-3 oils used in health supplements, are seen by some corporations as a potential source of big profits.
The Norwegian-based firm Aker Biomarine, one of the globe's leading krill fishing companies, recently applied to have its Antarctic krill fishery certified by the Marine Stewardship Council (MSC). The council attempts to provide market-based tools to promote sustainably caught fish. To accomplish this, the MSC works with fisheries, seafood companies, scientists, conservation groups and the public to promote the best "environmental choice" in seafood. Yet while the council's mission is important, certifying the krill fishery would stymie further efforts to more effectively conserve and manage Antarctic resources.
Certifying a fishery like Antarctic krill is far more complex than it may seem. Although overall catches appear relatively low as compared to total krill abundance, uncertainties exist about the local impact of fishing operations since they often overlap with the feeding areas of krill predators. When it comes to krill and other forage species, MSC's standards fall far short of achieving its goal of sustainability. In certifying a fishery, the council considers the sustainability of fish stocks - seeking to minimize environmental impacts and maximize effective management. The problem is that it measures mortality rates as though the animals were in an aquarium without predators. In reality, krill are part of a living system where there are many pressures apart from fishing. Yet, the MSC's process to assess potential krill certification does not take adequate account of the role that krill serve in anchoring the Antarctic food chain.
Furthermore, according to a recently published study by the National Science Foundation's Long Term Ecological Research Programme, "Over the past 50 years, winter temperatures on the
Peninsula have risen five times faster than the global average." Krill are sensitive to warmer waters and thus less abundant there. Nonetheless, climate change and the complexity of ecosystem interactions are not adequately accounted for in the current management process.
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http://www.guardian.co.uk/commentisfree/cifamerica/2009/apr/16/antarctica-global-warming-penguins