Trout Saviors 

Artificial insemination. Poisoned lakes. Decapitated cutthroats. It's all part of a paradoxical plan to save the state fish.

A limp westslope cutthroat trout lies on a cutting board, a fish biologist stands over it sharpening two knives, and over the radio comes U2's Bono belting out "In The Name of Love."

The song doesn't register with the half-dozen Montana Fish, Wildlife and Parks (FWP) biologists who form a fish disassembly line here in a makeshift lab at the Washoe Park Trout Hatchery in Anaconda. It's the only hatchery in Montana that preserves genetically pure westslope cutthroat trout, classified by the state as a "species of concern" after decades of habitat loss and hybridization with rainbow and Yellowstone cutthroat trout.

On this May day, for only the second time in more than 25 years, the biologists kill wild male westslope cutthroat trout plucked from the South Fork of the Flathead drainage and extract their sperm in order to artificially inseminate hatchery eggs. The idea is to infuse the hatchery's brood stock with new, wild Oncorhynchus clarki lewisi genes. The infusion will improve the genetic integrity of the hatchery trout used to stock degraded fisheries in the same drainage where the genes originated. And so the fish sacrificed today will, paradoxically, help ensure the species' long-term survival.

photos by Cathrine L. Walters

The state biologists, led by hatchery manager Mark Sweeney, work in a garage, isolated from the hatchery's some 164,000 westslope cutthroats. Cutting boards, knives, forceps, test tubes and various containers cover a long white table, and the biologists, resembling chefs behind a sushi bar, slice and dissect.

Outside, a truck sits idle. Minutes earlier it arrived with about 120 of these young, male westslope cutthroats from the Flathead's Sekokini Springs Isolation Facility, where the fish had lived since they were taken last fall from Knieff and Paint creeks, tributaries of the South Fork of the Flathead. In all, fish genes from about 15 South Fork tributaries will be taken over the course of the three-year infusion.

"It's all an effort to restore pure westslope cutthroat to the South Fork, and for statewide purposes," explains FWP Fish Health Coordinator Ken Staigmiller as he waits for another fish, turned belly-up by a lethal dose of anesthetic just moments before, to arrive at his fish-cutting station.

The biologists often use the words "pure" and "wild" to explain their work. The words seem out of place, considering there's nothing wild about the artificial insemination. The same has been said of FWP's larger restoration effort, known as the Westslope Cutthroat Trout Conservation Project, which involves poisoning lakes to kill hybrid trout and replacing them with "wild" fish from the Washoe Park hatchery. This level of human intervention is required, the state decided, to save the species. Some doubt the agency's motives are as pure as the cutthroat genes it's working to preserve. But, in any case, the project serves as an example of how convoluted native fish conservation has become in Montana.

Staigmiller receives the next fish, lays it out on the cutting board, and slices off its head. He puts the head in a small plastic baggie with the handful of others.

••••

University of Montana and FWP Geneticist Robb Leary determined in 2007 that the agency needed to infuse new genes into the Washoe hatchery brood stock.

"We were seeing a few more slight developmental abnormalities in the fish"—like changes in fin morphology—"than we did when they were originally established," explains Leary, who has inspected the brood stock since its first generation arrived in 1983 and 1984.

"But the main thing," he continues, "was that these fish have been held in isolation ever since then, and when you keep a population in isolation, you're always going to build up some level of inbreeding. Another thing is the population starts to adapt to the hatchery environment. And so that was really the impetus behind it. It's like a rancher deciding it's time for fresh blood."

FWP biologists go to great lengths to ensure that the fresh blood is free of disease. After Staigmiller opens a fish he cuts out its kidneys and spleen and drops them into a small glass test tube.

"We're not looking for any bacteria," Staigmiller says. "We're looking for certain bacteria—certain bacteria and viruses that we know are problematic. There are three bacteria, three viruses and one parasite that we basically have to certify this stock is free of before we can move on."

The parasite is Myxobolus cerebralis, which induces whirling disease. The disease leads to skeletal deformation and neurological damage that causes fish to swim in an uncontrolled whirling motion. Staigmiller's plastic bags of fish heads are headed to a lab in Bozeman to be tested for the parasite. Scientists grind up the heads, put them in a centrifuge and add enzymes, which free up any whirling disease spores occupying the fish cartilage.

"This is such a valuable brood stock—it's captive and we've invested a lot of years and money into it—and so we're very protective of it, very concerned about bringing anything into the hatchery that's going to be incorporated into this brood stock," Staigmiller says.

After all, FWP biologists have high hopes for the hatchery's fish. Most of them will ultimately end up somewhere in the South Fork of the Flathead drainage as part of the Westslope Cutthroat Trout Conservation Project. The agency is entering the fourth year of the 10-year effort to restore native westslope cutthroat trout to the drainage, an area that accounts for about half of the 10 percent that remains of the species' historic range.

The project has proven contentious ever since it was originally proposed about a decade ago. Few dispute the importance of preserving westslope cutthroat, the state fish, but they do question how much the project sacrifices in order do so.

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