Whirling disease discovered in Springville State Fish Hatchery SALT LAKE CITY Late last week, fish pathologists with the Utah Division of Wildlife Resources discovered DNA evidence of Myxobolus cerebralis, the parasite that causes whirling disease, in rainbow trout at the Springville State Fish Hatchery.
Brook Trout infected with whirling disease.
Skeletal deformations, like these in a mature Brook trout, are caused by whirling disease.
Photo courtesy of US Fish & Wildlife Service

Whirling disease affects trout and salmon, resulting in deformations and neurological damage that cause the fish to "whirl."

None of the four-inch trout were stocked in Utah waters. Per DWR protocols, the population of 60,000 fish will be destroyed, and the hatchery will be shut down until a new water supply is secured. The infected fish, weighing approximately 6,000 pounds, are a small fraction of the one million pounds of fish raised annually in state hatcheries.

Surplus rainbow trout at the other hatcheries will ensure that plenty of fish are available to stock Utah waters in the coming year.

The discovery was made during routine disease testing of the young rainbows. While disappointed, DWR officials were not completely surprised. The Springville hatchery also experienced an outbreak in 2005 when whirling disease was discovered in the main water supply.

DWR Aquatics Section Chief, Walt Donaldson, notes that the agency is committed to stocking healthy fish, "Good science requires that we not stock infected fish. We discovered the problem, notified the Fish Health Policy Board and are committed to sustaining healthy fisheries."

The agency is taking another critical step as well. It is currently digging a well to secure a clean water source from an underground aquifer. Officials hope this measure will prevent future occurrences of the disease at the Springville site when it reopens.

The public can also help prevent the spread of whirling disease across Utah. Officials urge anglers to take the following steps when fishing in Utah waters: