Responsibility for monitoring state hatcheries and state waters for whirling disease fall under the responsibilities of Wade Cavender, fish health specialist. This involves duties such as the constant testing and surveying of critical tributaries feeding infected waters and recording any of the infected waters to show where parasites are and allow regional managers to manage accordingly.

Knowing where the disease is found is very important in trying to stop further spreading.

Duties also involve the constant testing of brood stock and eggs to make sure there are no signs of disease agents.

There are, at present, six main pathogens Cavender looks for — three are viruses, two are parasites and one is a bacteria.

As in the case of WD, if found in a hatchery, it may be costly, but it can be contained. If found in the wild, about the only thing that can be done is to try to stop it from spreading to disease-free waters. The cleanup and prevention measures afterward to protect contaminated hatcheries have cost Utah sportsmen millions of dollars.

Cavender is also working on vaccines to combat bacterial pathogens, such as those that cause cold water disease, which is found in Utah and is fatal to fish.

"We take a lot of things for granted because we don't have a lot of the diseases we had 50 years ago. But there are diseases out there that can wipe out a sports fishery, and we need to constantly do inspections to make sure they don't become a more serious problem," said Wilson.

Finding fish that are more compatible to Utah waters is another area of work being done the Logan center.

One such fish is the splake, a cross between a lake and brook trout. It is better able to fight off diseases, but its range is limited. It cannot, for example, be planted in some mid- and low-elevation waters.

The tiger trout, a mix between a brown and brook trout, is not as impervious to whirling disease but is more adaptable and possibly more popular.

While both fish are aggressive and tasty, it is the tiger that got the looks. The tiger is a strikingly beautiful fish. It features a maze of dark stripes, thus the name tiger, which are stenciled over a body of pale green and gold. Its lower fins are a yellowish orange.

One fish that failed to make it into the Utah system was the brownbow, a cross between a rainbow and brown trout. The fish was slow growing and costly to raise.

"With so many of the hybrids, they sound good on paper, but in reality the percentage of survival in a hatchery is very low, and they are just not practical to raise," said Wagner.

"One big advantage to raising hybrids is they are sterile. In some waters we get more reproduction than we want. With sterile fish we can better control the population."

The Ho-Ha is a true rainbow and can reproduce, and because it is Utah's most popular game fish and is more resistant to WD, it is an ideal introduction.

The Ho-Ha is a cross between a rainbow from Harrison Lake, Mont., which has proved to be more resistant to the whirling disease parasite, and a rainbow trout from Germany from the Hofer strain, which has proved to be even more resistant.

The center has also become a main source of fish in the recovery program of the June sucker and is working on the survival of the endangered leatherback chub.

The Logan center is, in fact, important to the overall Utah fishing program.

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E-mail: grass@desnews.com