One new tool biologists with the Idaho Department of Fish and Game have been investigating is stocking alpine lakes with super-male brook trout.
Once they are stocked into the wild, all the offspring they produce with wild female brook trout will be males. In theory, this would skew the sex ratio of the population to being all males. Once there are no more females in the population, and the population is no longer viable native fish can be restocked in the lakes.
LINK (via Coeur d’Alene/Post Falls Press)