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Page 1 | Page 2 | Page 3 | Page 4 The Ultimate SinkLike Levin, Tony Koslow received graduate training at Scripps before moving on to a career that includes deep sea research. He was influenced by John Dove Isaacs, the maverick Scripps scientist who was a pioneer in studying seamounts and creating new ways to study and photograph deep-sea animals. After working as a fisheries oceanographer, Koslow spent ten years studying the previously unknown and extraordinarily rich marine life on seamounts at the Commonwealth Scientific and Industrial Research Organization (CSIRO) in Australia. There he developed acoustic and egg survey methods to monitor deepwater fish species, including the orange roughy and blue grenadier. While the orange roughy has become a popular dish at seafood restaurants, its situation is delicate because it can't easily rebound from severe depletions due to a 150-year lifespan and late maturation. 
"Since the 1980s, we have seen virtually every orange roughy stock in the world fished down to less than 10 percent of its original size," said Koslow. While at CSIRO, Koslow's work led to one of the world's first deep-water marine reserves. He was recently recruited to Scripps to lead the California Cooperative Oceanic Fisheries Investigations (CalCOFI) program, and he continues his efforts to protect and conserve deep sea life through marine protected areas. In his 2007 book: "The Silent Deep: The Discovery, Ecology, and Conservation of the Deep Sea," Koslow provides a historical analysis of discoveries, along with a detailed description of deep-sea ecology. The most stirring accounts in the book, however, are those that describe the imprint of the human footprint on the deep, even in the most remote reaches of the abyss. 
Technological advances in commercial fishing, Koslow uses as one example, have devastated deep-sea habitats. "When trawlers go through sensitive habitats in the deep sea, such as deepwater coral reefs, it's like clear-cutting a forest," said Koslow. A variety of human contaminantsÑfrom garbage to pesticidesÑoften sink to the ocean depths, making the deep "the ultimate sink" for many pollutants, according to Koslow. But Koslow believes that the most imposing threat may be human-induced climate change. As global warming accelerates, the deep will be threatened on several fronts. Increased infusions of carbon dioxide levels will make the deep seaÑas the rest of the oceanÑmore acidic, causing problems for many deep-sea habitats. Methane-hydrate deposits locked away in the deep could destabilize in a warming ocean and release massive quantities of carbon and accelerate further warming. Yet another threat comes from ocean circulation. Climate models predict that global warming will cause a broad weakening of circulation in the deepest areas of the ocean, choking off links to oxygen-rich near-surface waters and increasing deep oxygen minimum zones. "There will be less and less oxygen going down there. If that happens, the deep sea will just grow more stagnant," said Koslow. "The climate changes we're causing now will continue for a long time to come and those changes could have great impact on the deep sea." Next Page: The Deep Moves Closer |
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