BACTERIA-INFESTED FISH BLAMED FOR BIRD DEATHS.

Byline: Matthew Fordahl Associated Press 

Saltwater bacteria that can infect people have been found in dying fish linked to the deaths of more than 13,000 birds at the Salton Sea, wildlife experts said Wednesday.

The Vibrio alginolyticus bacteria produce a toxin that can cause skin irritation and diarrhea in people who eat infected fish or expose wounds to contaminated water.

So far, no human cases have been reported at the Salton Sea.

The latest finding is another link in a chain of infections apparently triggered by the 240,000-acre lake's harsh environment and pollution. Researchers speculate the birds died after eating fish sickened by the bacteria and further infected with the avian botulism toxin.

For the first time, the finding opens the possibility of people becoming sick from eating fish or swimming at California's largest lake.

Despite that potential, Imperial County health officials only plan to post warnings at bait shops - not along the beaches of the sprawling lake 150 miles southeast of Los Angeles.

``It will be a reminder to fishermen to refrigerate the fish after they boat it and examine their fish to see if it's healthy,'' said Tom Wolf of the Imperial County Environmental Health Division.

Indications of infection include bleeding from the base of the fins and gills, lethargy and bloating, said Frank Shipley of the U.S. Geological Survey's Northwest Biological Science Center in Seattle.

The tilapia fish examined at Shipley's lab were so sick that they appeared to be rotting alive. ``These were massive, acute infections,'' he said. ``When we opened these fish up they were definitely on their way out quick.''

The findings further support a theory that the dead birds, primarily fish-eating pelicans, were infected by fish. Biologists were mystified at the bird deaths, since pelicans normally eat only live fish, not rotting carcasses.

Despite the identification of the bacteria, biologists said more research is needed to find out how prevalent the bacteria are among other species of fish and in the water of the Salton Sea. Other tests will show the source of secondary infections.

The diseased tilapia, an African fish introduced to the Salton Sea, may have also been more susceptible to the bacteria because of shock caused by the sea's salinity, pollution and temperature, officials said.

The infection, which cause the fish to rot alive, create hospitable conditions for other bacteria that create botulism believed to be killing the fish-eating birds. Last month, researchers announced they found the toxin in some of the tilapia.

``We know the fish are sick with bacteria and dying. We know some are positive with botulism toxin,'' Shipley said. ``We know birds are eating fish and dying, but we don't have a precise link between the sick fish and the botulism spore germinating in the gut of the sick fish.''

As of Wednesday afternoon, 13,041 birds, including 1,110 endangered brown pelicans, have been killed.