Northwest Researchers Working To Save Lonely, Homely Fish

By Stephanie Cartier

Some say it's one homely fish, but the eel-like burbot is catching the attention of researchers in the Northwest. Once a staple for anglers along the banks of the lower Kootenai River, burbot are becoming harder and harder to find.

Despite the unusual appearance of the fish, they have an appealing taste–some even liken it to lobster. In fact, the Kootenai River used to be a haven for those fishing for a bite of burbot. Pictures from earlier days show trucks piled high with the sought-after fish. Vaughn Paragamian of Idaho Department of Fish and Game says other lakes in North America that were also known for burbot stock couldn't compete with the harvest from Kootenai River. "We're talking thousands of fish in the harvest versus hundreds in these other lakes,” he said. "So it was a substantial fishery at one time.” But eventually things changed, and burbot populations dwindled.

Many experts point to the completion of Montana's Libby Dam in 1975 as a major contributor. The 7.6 million tons of concrete dams up Lake Koocanusa and provides hydroelectric power to thousands and helps control floods, but it is deadly to fish. "There were many factors that contributed to the decline,” points out Montana Fish, Wildlife and Parks' Jim Dunnigan. But he adds, "It's been pretty recently that the dam has kind of been the final straw, at least in the lower river, that has contributed to the decline.”

While the Kootenai River and Kootenay Lake, B.C., used to be overflowing with thousands of burbot, today, officials at Idaho Fish and Game estimate that only sixty fish are making their way through the lonely waters of the river. And it's slim pickings for spawning. So in a collaborative effort between Montana, Idaho and British Columbia, scientists are trying to determine the best way to save the dwindling burbot population.

"We know that with only 60 fish left, that we're probably at or beyond functional extinction from the Kootenai River burbot as we know it, so the question arises, are we going to rehabilitate Kootenai River burbot or are we doing to rehabilitate burbot in the Kootenai River?” says Paragamian. Because there's a lot of genetic variability within the same species of any animal, researchers first need to determine how similar the fish in the Kootenai River are to their relatives in other parts of the Pacific Northwest. At the same time, notes Paragamian, they cannot overlook the needs of the native burbot population.

"It makes sense that if you're going to use fish cultures in a hatchery type of environment, to either re-found the stock or rebuild it, that you'd want to use the most closely genetically related population that's feasible,” says Dunnigan. Now it's a matter of finding the right fish.

Working to answer that question is Matt Powell, a researcher at the University of Idaho. In 1999, Powell and Paragamian found that burbot above Kootenai Falls are, in fact, genetically different from burbot below the falls, an observation which Powell attributes to the populations being separated for so many years. "We found that the falls themselves serve in some way as a barrier to gene flow because the animals that go down through the falls can't get back up to spawn with animals above the falls.” Now, he's trying to put that difference in context with the bigger picture. If it turns out that the difference between burbot above and below the falls is slight, but the difference between those fish and other fish from around the region is great, the Kootenai River burbot would actually be a distinct species. Fish managers would need to know how to more effectively maintain the river to make it friendlier to the fish in an attempt to save it.

While the fish are not currently listed as an endangered species, they are a species of special concern. And while other burbot populations may be faring better than those in the Kootenai River, none of them is doing great. Burbot numbers worldwide have been declining due to a variety of factors. "So when people say, oh, well, the burbot in the Kootenai River aren't important because they're doing well elsewhere, it's not true at all,” says Paragamian.

But the Kootenai River burbot are facing some serious threats. "It probably isn't all due to Libby Dam, but a lot of it is,” says Paragamian of burbot decline. The fish aren't strong swimmers, and since the dam was built, swimming upstream isn't as easy as it used to be. "The high flows that are normally released from Libby Dam during the wintertime impair burbot movement and actually push some fish downstream.”

Despite being in hot water figuratively, burbot are also in hot water literally. The water released from Libby Dam comes from Lake Koocanusa, which Paragamian compares to a bathtub of warm water after gathering the sun's heat all summer. Water released in the winter, in large volumes, retains its heat well, despite the frigid air temperature. By lowering the flows from the dam, Paragamian says, water temperatures would drop and burbot habitat would improve dramatically.

While a lonely burbot looking to spawn may be getting desperate, there is hope for rehabilitation. Other places where numbers were down have had success by simply changing the habitat. "If you have habitat, the right habitat, burbot have been very, very resilient in recovery or rehabilitation,” says Paragamian.

So that leaves the task of finding a donor stock to rehabilitate the Kootenai River burbot. "What we're looking for basically with our large sample of burbot throughout the Pacific Northwest here, is to find a stock of fish that's more genetically and even behaviorally similar to the stock of fish that was once very, very abundant in the Kootenai River in Idaho and British Columbia,” says Paragamian.

Paragamian and Powell, with the help of wildlife officials from Idaho, Montana and British Columbia, have collected about 800 samples of burbot tissue from 22 populations all around the Northwest. By looking at mitochondrial DNA, which is only passed down through the mother, Powell is able to get an idea of how the animals dispersed throughout the various lakes and rivers over time.

Powell plans to present his data at the Second International Burbot Symposium in Anchorage this fall, where burbot managers and researchers will put their heads together to discuss the status of the fish. "It's a good partnership,” says Powell.

"I think the study is really exciting because number one, it's not only the first study of its kind within the region, but it's the first study of its kind within the country or even worldwide that's looking at the genetic structure of burbot. I think it's really going to open the doors for some exciting stuff for future studies,” says Dunnigan. "It's an important piece of information that we need to better manage the species as a whole, not only within the Kootenai but within its native range.” He adds that the researchers want to learn something that transcends state and national boundaries because "the fish don't really respect the lines on the map.”

Stephanie Cartier is pursuing a master's degree in Technical Communication from the University of Washington.