http://hisz.rsoe.hu/alertmap/index.php?smp=&lang=engArea: USA, State of Alaska, Yukon River area,
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More Alaskan salmon caught here end up in the dog pot these days, their orange-pink flesh fouled by disease that scientists have correlated with warmer water in the Yukon River. With global warming, cold-temperature barriers are giving way, allowing parasites, bacteria, and other disease-spreading organisms to move toward higher latitudes. "Climate change isn't going to increase infectious diseases but change the disease landscape," said marine ecologist Kevin D Lafferty, who studies parasites for the US Geological Survey. "And some of these surprises are not going to be pretty." The emergence of disease in Alaska's most prized salmon has come as a shock to fishermen and fisheries managers.
Alaskan wild salmon has been an uncommon success story among over-exploited fisheries, with healthy runs and robust catches that fetch high prices at fish markets and restaurants in Los Angeles, New York, Tokyo, and London. Fishermen and regulators who have cooperated to save species from overfishing and local environmental hazards have been caught unprepared to deal with forces beyond their control: how to manage a fishery for climate change. The return of the king -- or chinook -- salmon, the biggest of the species, is eagerly anticipated along the Yukon. Savvy buyers from Japan converge on the docks near the river's mouth to purchase these fish that have bulked up with extra fat to swim more than 2000 miles (3220 km), across Alaska, to spawn in the stream of their birth.
As a fierce defender of the fish's reputation, Gene Sandone, a regional supervisor for Alaska's Fish and Game Department, was less than receptive to complaints from Tanana fishermen such as Moore that something was wrong. The chinook salmon they pulled from the Yukon River about 700 miles (1127 km) inland didn't smell right. It wasn't an instant, gag-inducing stench. It was more subtle but grew into an unpleasant odor of fruit rotting in the hot sun. More important, the flesh turned mealy. The salmon didn't dry right in smokehouses either. Instead of turning into rich red strips of salmon jerky, it turned black and oily like strips of greasy rotten mango. "If you don't weed out the bad ones, it'll stink up the whole smokehouse," Moore said, wielding a knife on his cutting table. "I only want the good stuff. I don't want second-rate fish." Salmon jerky strips are a staple among the Native Americans and subsistence fishermen in rural outposts such as Tanana, a village of 270 people. "It'll keep you warm in the winter," said Lorene Moore, Pat's wife and a native of the village. In Alaska's bigger cities, these strips are a prized delicacy, fetching USD 20 or more a pound. A friendly federal biologist advised the local fishermen that they should send samples, including hearts and organs, which were covered with tiny pimples, to the Center for Fish Disease Research at Oregon State University.
The Oregon lab quickly identified the problem as "white spot disease," caused by a microscopic parasite called _Ichthyophonus hoferi_. Ich (pronounced "ick") is a well-known disease, harmless to humans, that was blamed for devastating losses in the herring fishery in Scandinavia. A similar parasite can infect aquarium fish.
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another food source degraded
tick, tick
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