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Thursday, Sep 18, 2014
Health & Fitness

Botulism outbreak killing ducks at refuge

Published:   |   Updated: August 30, 2014 at 01:11 AM

GRANTS PASS, Ore. (AP) An outbreak of botulism has killed thousands of ducks at Tule Lake National Wildlife Refuge in Northern California.

The outbreak going on since July is not unusual, but it has been exacerbated by the drought, U.S. Fish and Wildlife Service spokesman Matt Baun said Friday.

The refuges along the Oregon-California border have not received any irrigation water since November, Baun said.

In non-drought years, the refuges get water after it has run through farms on a nearby federal irrigation project, but there has been none to spare this year. An agreement that would give more water to the refuges has been stuck in Congress, blocked by House Republicans. The agreement is linked to another that would remove four hydroelectric dams from the Klamath River to help salmon.

That has left the Lower Klamath refuge dry, pushing more ducks into the water left at Tule Lake.

Wildlife biologist John Beckstrand said they have picked up 5,000 dead ducks to limit the spread of the disease, and there are probably 5,000 more hidden in the tule plants that they couldn't find. Ducks will continue dying from the disease until hunting season starts in October. About 90 percent of them are mallards, but there are also pintails, greenwing teal and shovelers. The gadwalls are less susceptible to the disease. Most of the mallards are hens that cannot fly because they are molting.

An aerial survey last July counted 125,000 birds at Tule Lake refuge, Beckstrand said.

Botulism is naturally occurring in the soil, and there are generally outbreaks every two out of three years, Beckstrand said. This year's outbreak probably will rank in the top 10, he said. Hot weather tends to make it worse.

"The problem is with this drought, everything is so dry," Beckstrand said. "Lower Klamath refuge is dried up now. There are more birds than you would have normally on Tule Lake."

So little marsh is flooded that many of the waterfowl migrating north this fall on the Pacific Flyway may well pass by without stopping, he added.

An analysis by Fish and Wildlife has determined that if the Klamath Basin Restoration Agreement were in force this year, there would be 48,000 acre feet of water enough to cover 48,000 acres one foot deep for the wildlife refuges, Baun said. That would be enough to flood the marshes at Lower Klamath Lake.

Jim McCarthy of the conservation group WaterWatch said Fish and Wildlife also needs to change a policy that allows farmers to grow crops on the refuges, which mean less water for marshes.

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