Biologists hope to revive white sturgeon in Kootenai
February 8, 2006
According to an article in the Columbia Basin Bulletin Weekly Fish and Wildlife News, fisheries biologists are attempting to revive dwingling populations of wild white sturgeon in the Kootenai River below Libby Dam. Last summer, more than a million fertilized white sturgeon eggs were released in to the Kootenai River upstream of Bonners Ferry, Idaho.
Sturgeon populations have shrunk considerably since the 1970s due to human-caused changes to the river’s course and flow, especially with the building of Libby Dam in 1973, which greatly changed the natural flow patterns of the river. To date, recovery attempts for the species have been largely unsuccessful, according to the article.
“Despite long-running research, it remains largely a mystery why wild production by the huge fish continues to fail. The fish spawn, but not enough hatch and/or survive to maintain the population.”
The Kootenai River white sturgeon was listed at endangered under the Endangered Species Act in 1994.
In June, Kootenai Tribe of Idaho and Idaho Department of Fish and Game officials fertilized the eggs aboard boats and released them into the river where currents and river bottom habitat seems conducive to hatching success. About half of the releases were in the canyon above the Kootenai's confluence with the Moyie River and half in the braided reaches between Bonners Ferry and the Moyie.
Unlike most white sturgeon, Kootenai fish are not anadromous, do not migrate to the ocean. They have been isolated since most recent Pleistocene glacial period --approximately 10,000 years -- in the area between Kootenai Falls, Mont., and Bonnington Falls, British Columbia, a 270 kilometer reach that includes Kootenay Lake. Bonnington Falls are downstream of the lake.
Later this year, biologists will gill-net stretches of the river in search of juvenile fish, which will determine if last year’s program to release fertilized eggs was successful.
Related Links:
The Columbia Basin Bulletin
|
