Triploids Finally Find Acceptance
All of a sudden, fisheries agencies are high on sterile trout.
Biologists, many of whom once derided the stocking of genetically altered trout called triploids, now believe the fish have a place in fisheries management.
They’ve not only accepted the the sterile triploids as fish that can create fishing for trophy-sized four or five years after they’ve been stocked. They’re using the triploids to provide new kinds of fishing opportunities for anglers of all ages and fishing experience.
The Idaho Fish and Game Department is using the triploids to protect the purity cutthroat trout. The department stocks only sterile trout the lower reaches of streams such as the Coeur d’Alene or St. Joe.
About 44,800 triploid rainbows weighing 1-1/2-3 pounds, will be in 43 Washington lakes for the opening of the general fishing season April 29. Plans call for releasing 17,800 in Eastern Washington lakes.
Plants of triploids in the Spokane region lakes follow: Clear, 1,500; Liberty, 2,500; Newman, 3,750; West Medical, 700, and Bennington in Walla Walla County, 750.
Two Columbia Basin Lakes have been stocked with triploids: Spectacle in Okanogan County , 2,000, and Wapato in Chelan County, 1,450.
There are no special regulations for Clear, Liberty, Newman, West Medical, Bennington and Spectacle. The six lakes also hold a variety of fish species. Newman has a growing population of tiger muskies.
Wapato is open April 29-Oct. 31. However, selective gear rules apply from Aug. 1-Oct. 31 and all fish must be released.
Washington officials say they are focusing on triploids to help take a little of the sting anglers have felt from losing steelhead and salmon opportunity.
The department chose to stock lakes primarily in urban areas so that the maximum number of fishers could take advantage of the opportunity to catch big trout. If the trout are not caught this year, they can provide true trophy fish catching opportunities in future seasons.
Trout are sterilized by heat or pressure treatment in the egg stage to alter chromosome development, leaving them with three sets of chromosomes instead of two and thus referred to as “triploids. The fish grow extra large because they spend all their energy feeding and growing instead of trying to reproduce.
The department has been stocking several Eastern Washington lakes with triploids for several years. Among the lakes that have been planted with the sterile fish are Amber, Dry Falls, Quail and Aeneas.
Plans call for stocking North Silver, Lenice, Nunnally, Chopaka and several other lakes with triploids this year and next. Lenice and Nunnally were rehabbed last month.
Jim Fredericks of Coeur d’Alene, Panhandle regional supervisor for the Idaho Fish and Game Department, said the primary reason why his agency is producing sterile trout is to protect further cutthroatrainbow hybridization. Because sterile fish can’t reproduce, they would be no threat to the purity of cutthroat.