SALT LAKE CITY -- Despite a recent discovery of whirling disease being spread into Utah from an adjoining state, the greatest threat to the spread of whirling disease in Utah still lies within the state itself, officials say.

"I would say this was unusual," Joe Valentine, aquatic culture supervisor for the Utah Division of Wildlife Resources said after whirling disease was confirmed in cutthroat trout examined by Division fish pathologists in Geyser Ditch, a small stream in the LaSal Mountains in southeastern Utah.

It's believed the disease, which causes various deformities and sometimes death in young trout and salmon, was spread to the stream from whirling disease positive fish stocked by the Colorado Division of Wildlife in Colorado's Buckhorn Reservoir, of which Geyser Ditch is a tributary, said Chris Wilson, fish health specialist at the Utah Division of Wildlife Resources' Fisheries Experiment Station.

While Valentine said it's possible the disease could be spread from an adjoining state in the future, it's more likely whirling disease in Utah would be spread within the state itself.

The good news is that of the almost 1,000 sites stocked annually in Utah, only 64 have tested positive for Myxobolus cerebralis, the whirling disease parasite.

Valentine hopes that with the help of anglers and private pond owners, it will stay that way.

Anglers can do much to help prevent the spread of whirling disease, by following a few simple rules:

* Clean all equipment of mud (boats, trailers, waders, boots, float tubes and fins) before leaving your fishing water. Thoroughly dry equipment in the sun, if possible, before reuse. If you are traveling directly to other waters, clean your equipment with a strong solution of chlorine bleach or use another set of equipment.

* Don't dispose of fish heads, skeletons or entrails in any body of water. Fish parts should be disposed of in the garbage, by deep burying or by total burning.

* Don't transport live fish between bodies of water. This practice could spread disease and is strictly illegal.

* If you observe the symptoms of whirling disease in fish (various deformities of the head, twisted spines, a black tail or fish swimming in whirling motions), or if you observe illegal fish stocking, contact your local Division conservation officer or call the Division's poaching hotline at 1-800-662-3337.

Valentine reminds private pond owners that they must obtain a permit before building a private pond in Utah. Requiring pond owners to do so allows the Division of Wildlife Resources to control prohibited diseases, including whirling disease, in each private pond in the state, Valentine said.

Pond owners also are reminded that they may not take fish from the wild and plant them in their ponds. This illegal practice could result in whirling disease and other diseases being spread from one watershed to another, Valentine said.

"Relocating fish may establish new species and strains of fish in watersheds where they don't belong, which may harm native fishes and upset fisheries management plans and the success of those fisheries," he said.

While there isn't much that can be done to prevent birds from feeding on whirling diseased fish and then spreading the disease, the Division's rebuilt Kamas Fish Hatchery will have raceways that are completely covered, preventing birds that may have fed on infected fish from spreading the disease to the hatchery.

Presently, all of the Division's 10 sport fish hatcheries are certified whirling disease-free, Valentine said. Each hatchery is tested annually, with hatcheries in close proximity to whirling diseased waters tested twice each year.

It will pay for anglers to follow the tips provided, as the spread of whirling disease in Utah could have a significant impact on the future of the state's fishing.

For example, Utah's favorite fish -- the rainbow trout -- is the fish most susceptible to being infected with the whirling disease parasite. Should whirling disease spread to enough of Utah's rainbow trout fisheries, the enjoyment of catching Utah's favorite fish may be lost.

Brook trout and kokanne salmon also are susceptible to the disease, as are Utah's native trout, the cutthroat.

"As far as our native cutthroat trout populations go, we don't want whirling disease to be the straw that breaks the camel's back," Valentine said.

The trout population in Geyser Ditch is a wild cutthroat population and because of the small size of the fish, whirling disease in the ditch may have a devastating effect on it, as it could on all other native cutthroat trout populations in Utah where the disease may spread.