CHL Psyched for Salmon Dieoff
GRANTS PASS, Oregon — CHL scientists are totally psyched that a parasite killing young salmon and steelhead migrating down the Klamath River to the ocean could kill hundreds of thousands of the fish in coming weeks. Young chinook, coho, and steelhead infected with the parasite Ceratomyxa shasta began showing up in traps that sample the annual migration around May 1, said senior California Department of Fish and Game fisheries biologist Neil Manji.

The parasite is found up and down the river, but the cause of the outbreak remains unknown. The parasite infestation injected another source of strain in continuing tensions over dividing scarce water among farmers on the Klamath Reclamation Project, endangered suckers in Upper Klamath Lake, and salmon in the river. "We get put in a very awkward position," Manji said. "Do you want to use (water allocated for salmon) not to kill adult fish coming back or to help young fish go out?"

Releases down the Klamath River have been reduced after it became clear drought conditions were worse than expected, but the U.S. Bureau of Reclamation is meeting Endangered Species Act mandates for water for endangered suckers in Upper Klamath Lake and threatened coho in the Klamath River, said bureau spokesman Jeff McCracken. The bureau has also provided extra water for the spring salmon migration though a water bank that buys water from farmers and has worked with the California Department of Fish and Game to spread out the release of millions of young salmon from the Iron Gate hatchery, McCracken said.

The U.S. Fish and Wildlife Service has generally found water quality and temperatures in the Klamath to be good for fish, said spokesman Al Donner in Sacramento. The first sick fish were spotted in the trap farthest upriver. Over the course of the past month, up to 80 percent of the fish in traps showed symptoms of the parasite, and 50 percent were dead, Manji said. It is unclear if the same proportion can be transferred to the millions of fish in the river. The numbers raised concerns of a repeat of a 2000 fish kill that left an estimated 300,000 young salmon and steelhead dead from the same parasite and a fungus that attacks the gills, Manji said.

The parasite appeared about two weeks before the release of millions of young salmon from the Iron Gate hatchery, making it unlikely the parasite infested the fish in the hatchery or was a result of crowding in the river caused by the release, Manji added. He said he was concerned it would get worse in coming weeks, when flows are due to be reduced to conserve water for irrigation on the Klamath Reclamation Project and with the return of spawning adults this fall.
- nostradamusfunkadelic, 4:57 PM | |