Alaska’s prized wild salmon are suffering from a disease that scientists suspect of being boosted by — you guessed it — global warming. The emergence of Ichthyophonus as a threat to king salmon has coincided with a steady warming of Yukon River water over the past few decades, which scientists say has welcomed cold-averse parasites northward. “Climate change isn’t going to increase infectious diseases but change the disease landscape,” says federal marine ecologist Kevin D. Lafferty. “And some of these surprises are not going to be pretty.” Literally: Fish infected with “ich” become covered in white, pimply spots, smell funky, and produce mealy, oily flesh. One independent researcher estimates that perhaps 20 percent of king salmon are dying of ich before reaching spawning grounds. If so, fisheries would do well to cut back commercial catches by an equal amount to maintain a healthy population; so far, Alaska’s Fish and Game Department has largely chosen to ignore the problem.
