Colorado’s rainbow trout were almost wiped off the map more than 10 years ago from Whirling Disease. The Colorado DOW have been crossbreeding a German species of rainbow called a hofer and other rainbow strains to create franken-fish that now appear to be highly resistant to the disease. Read the whole press release here.

Whirling disease is caused by a microscopic parasite that passes through the fish’s skin. The organism attacks the cartilage of young fish and distorts the spine. Thus causing the fish’s spine to curve and greatly reduce it’s ability to survive. The affected fish “whirl” around in circles making escape from predation and feeding almost impossible.

While this all sounds hunky dory for anglers, I’m curios to the long term ramifications of cross breeding hatchery fish to fend off parasites that seem to be in the ecosystem for some reason or another. Sometimes it takes a long time to realize we (humans) have made a mistake by playing god. What’s your take on the situation? Good? Bad? Or don’t you care as long as they’re are big fat fish fish in the river for the time being?


Photo Credit: Colorado Division of Wildlife

This is a cross between a Hofer rainbow trout and a strain of rainbow
that the DOW has used for many years. The Hofer cross rainbows grow more quickly than the traditional rainbows. This fish, hatchery raised for
brood stock, is about 18 months old.