WASHINGTON DEPARTMENT OF FISH AND WILDLIFE
NEWS RELEASE
600 Capitol Way North, Olympia, WA 98501-1091

March 22, 2001
Contact: Madonna Luers, 509-456-4073

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Tucannon loses 80,000 rainbows to trichodina; southeast Washington trout stocking reduced

About 80,000 catchable-size rainbow trout, destined for release this spring into southeast Washington fishing lakes, have died from an external parasite outbreak at the Tucannon Fish Hatchery in Columbia County.

The outbreak of "trichodina" started in early March in a three-acre earthen rearing pond at the hatchery. Trichodina is a ciliated external protozoan commonly found on the skin and mucous of fish raised on surface water. It does not typically cause mass losses of fish and it is not a health risk to humans.

Washington Department of Fish and Wildlife (WDFW) hatchery workers quickly began a formalin treatment of the fish in the pond, but the parasite persevered, even at higher dosages, and fish continued to die.

Formalin is the "drug of choice" to treat the parasite, explained WDFW fish health manager Kevin Amos, but rainbow trout are more sensitive to it than salmon. "It's sometimes a fine line between which is killed by formalin first, the fish or the parasite, " he said.

Pond size, water flow, and low seasonal water temperatures made treatment challenging, Amos said. Last week hatchery crews started a treatment with potassium permanganate and finally stopped the spread of the parasite. Unfortunately 80,000 fish died as a result of the protozoan outbreak. Other fish exposed but recovering will not be stocked out until they are healthy.

The loss means trout stocking plans for southeast waters had to be changed, said WDFW regional fish program manager John Whalen. Twenty thousand catchable-size trout from WDFW's Ford hatchery will help fill the gap, but southeast waters will receive approximately 62,000 fewer eight-to-nine-inch size trout this year.

The table shown below reflects what had been planned for southeast waters, and what is now being stocked. Fishing waters scheduled to receive triploid trout later this spring will be receiving their original allotments of the one-to-1-1/2-pound fish, including Bennington Lake (2000, with 1200 donated by Tri-State Steelheaders Club), Quarry Pond (400), Golf Course Pond (300), and West Evans Pond (300). The stocking numbers in the following table include these triploids.

Name of LakePlanned AllotmentStocking Allotment
Asotin County
Golf Course Pond20,60015,100
Headgate Pond2,0002,000
Silcott Pond4,0003,000
West Evans Pond21,20015,200
Columbia County
Beaver1,5001,500
Blue Lake21,30018,300
Big Four2,8002,800
Curl Lake15,30013,300
Dam Pond2,0001,000
Dayton Juvenile Pond3,1003,100
Deer Lake 3,0002,000
Donnie Lake600600
Orchard Pond2,0001,500
Rainbow Lake24,30017,800
Spring Lake11,30010,300
Watson Lake15,30010,300
Garfield County
Bakers Pond1,5001,500
Caseys Pond500500
Whitman County
Garfield Pond2,0002,000
Gilcrest2,0002,000
Pampa Pond5,2004,200
Riparia Pond2,0001,000
Rock Lake12,000 Rainbow trout
5,000 Brown trout
Stocked out of Ford Hatchery
Union Flat Creek1,500 Rainbow out of Spokane1,500
Walla Walla County
Bennington Lake26,20016,000
Bennington Lake2,000 triploid trout2,000
College Place Pond3,2003,200
Fish Hook Pond6,1005,100
Jefferson Park Pond2,1002,100
Quarry Pond24,70015,700
Franklin County
Dalton Lake20,30015,300
Marmes Pond2,0002,000
Adams County
Sprague Lake5,0000

In addition, during the first week of March WDFW released about 50,000 surplus juvenile steelhead trout into two waters in southeast Washington. Dalton Lake in Franklin County received 31,406 juvenile steelhead trout (4-6 inches in length) and Quarry Pond in Walla Walla County received 18,864. These fish, which are an anadromous form of rainbow trout, were excess Wallowa stock steelhead from Lyons Ferry Hatchery, and were not needed to meet steelhead program goals. The Wallowa River steelhead stock is being phased out of Washington's Snake River steelhead program because they do not meet National Marine Fisheries Service (NMFS) criteria for recovering threatened steelhead. These supplemental fish were stocked into Dalton Lake and Quarry Pond to provide additional angling opportunity above the planned allotment of catchable trout for these waters.