Bid to revive sturgeon spawns controversial plan
By Randy Boswell, Canwest News ServiceJune 9, 2010
Rod Silver (manager, Habitat Coservation Trust Fund) and guide Jessea Grice with a healthy Fraser white sturgeon, tagged and ready for release.
Photograph by: Undated Handout, PNGU.S. wildlife officials have begun a controversial experiment designed to encourage the white sturgeon — Canada's largest freshwater fish and one of this country's most critically endangered species — to swim upstream from waters in British Columbia and Idaho to historic spawning grounds in Montana that haven't been reached for decades.
Declared endangered in Canada in 2003, the white sturgeon — a species that has been around since the age of the dinosaurs — is now struggling to survive in the northwestern United States and the remaining four watersheds it inhabits in B.C., including the Kootenay River system.
The huge fish, which can grow to six metres in length and weigh 600 kilograms or more, is also famous for its longevity. Individual fish can live well beyond 100 years.
And although thousands of white sturgeon hatchlings are now released annually to bolster the Kootenay's imperilled natural population, those fish won't be old enough to reproduce for years and their fate is ultimately uncertain.
Meanwhile, the river's natural population — reduced by habitat disturbances from about 10,000 a half-century ago to fewer than 500 today — has not produced offspring in at least 30 years.
"We're trying to figure out how to stimulate spawning," said Gary Burton, the U.S. Fish and Wildlife Service's state supervisor for Idaho.
"They're a long-lived species, but we've got some old fish in the system and we're trying to get some new ones."
Now, in a bid to "coax" aging white sturgeon from B.C. and Idaho to take a long-overdue trip back to their forgotten, pebbly love nest in Montana, U.S. officials will open the floodgates Thursday at the Kootenay's main dam — and risk the wrath of water-starved boaters and cottagers further upstream on both sides of the border.
The project was initiated after a U.S. environmental group, the Arizona-based Center for Biological Diversity, filed a successful lawsuit demanding that U.S. federal agencies identify critical habitat for the white sturgeon and take measures to restore the species.
But the effort is complicated by the fact that the 781-kilometre river — with both its source and mouth in B.C. but much of its length in the U.S. — crosses the international boundary twice.
"It does add some layers to the thing that Kootenay sturgeon spend a lot of their time on the B.C. side of the border," U.S. federal biologist Jason Flory told Canwest News Service on Wednesday.
The eastern, upstream section of the river has no white sturgeon but includes the elongated Lake Koocanusa reservoir, a popular recreation area straddling the border in southeastern B.C. and northwestern Montana created by the construction of Libby Dam in 1975.
The lake's offbeat name is an amalgam of Kootenay, Canada and U.S.A.
The western section of the river, downstream from the dam, is where the sturgeon live. That part of the Kootenay extends into Idaho before flowing north back into Canada and through Kootenay Lake before emptying into the Columbia River near Castlegar, B.C.
The plan to flush more water through Libby Dam to the downstream section of the Kootenay is aimed at helping mature white sturgeon from Idaho and B.C. return to the river's best spawning spot — a rocky stretch of stream bed near Kootenai Falls at Troy, Montana.
Since the late 1970s, because of changes in the river's flow following the building of the Libby Dam, the white sturgeon have not reached the ideal breeding site that had been used for countless generations. Instead, eggs buried at an inferior location — a sandy stretch of stream bed in Idaho — are being suffocated every year before hatching.
But water levels in Lake Koocanusa have been worrisomely low in recent years, and the planned "sturgeon spill" downstream at the Libby Dam — which may or may not help the fish below — is certain to do one thing: further deplete the reservoir above.
Canadian and U.S. residents of the Koocanusa — many skeptical that sending more water to the lower Kootenay will convince sturgeon to swim farther upstream — recently registered their concerns with Flory and other U.S. officials at a public meeting in Wardner, B.C., just north of the U.S.-Canada border.
"I do think folks understand what we're trying to do," said Flory, who is working with both federal and provincial officials in B.C. to revive the region's white sturgeon populations.
"And most people do want to see the sturgeon recover — they support that. But there are impacts. It does affect lake levels . . . and for the past 10 years we've had a series of low-water years — so each year it gets harder and harder for folks to see a lower reservoir."
Added Burton: "That is the challenge. But we are required to balance the needs of the species as well as the needs of the public."
The extra flow through the Libby Dam will last about a week, said Flory, then scientists will wait to see if the wild sturgeon respond by moving upstream — out of Kootenay Lake and other gathering spots along the lower river — to rediscover their old Montana egg-laying site.
© Copyright (c) Canwest News Service
Author
Topic: Bid to revive sturgeon spawns controversial plan (Read 2074 times)