Monday, August 11, 2008


Photo by Keith Lazelle.

They're fish that swam with dinosaurs: The sturgeons, a 250-million-year-old fish family that has demonstrated a remarkable knack for survival. At least until now.

Various sturgeon species are found widely in rivers and lakes across Eurasia and North America. At one time, they were a common Idaho species, being found in the Snake, Salmon and other river systems.

Idaho sturgeon reached legendary size: up to 10 feet long and 350 pounds. Truly, dinosaurs swam our waters.
The Kootenai River population of sturgeon has been isolated due to waterfalls to northern Idaho, Montana and British Columbia since the last Ice Age. Like most sturgeon species, they survived millions of years of changes, but they may not be able to survive their latest obstacle: humanity.

The sturgeon's life history includes a list of factors that now endanger it: Sturgeons need clear, cold water, and lots of it--they move up and down rivers throughout their lives. They need wetland areas to spawn in addition to rivers. Females require about 30 years to mature and breed. And, of course, caviar is a delicacy--commanding extraordinarily high prices.

For the white sturgeon, the upstream Libby Dam and resulting changes in the Kootenai River (including loss of wetlands and river meanders) has put the Kootenai population in peril. Less than 700 adults remain. And the population is aging; very few young fish are found in the river.

Fortunately, all is not bleak for the Kootenai's white sturgeon. Restoring wetlands and tributary streams in the Kootenai Valley mean cleaner water and better habitat. The Nature Conservancy has restored more than 400 acres of wetlands on its Ball Creek Ranch Preserve, and other organizations and agencies have similarly restored other wetlands throughout the valley.

Can these make a difference? It's hard to say, but last year kokanee salmon--another species that needs clear, cold water and tributary streams--returned to spawn in Ball Creek after being absent for more than four decades.

The Kootenai Tribe is also playing an important role, by rearing sturgeon in a hatchery and releasing juveniles in the river. With this imperiled population, clearly supplementing the wild fish will remain an important aspect of sturgeon conservation.

It will take time, but there's hope that these efforts will help restore these giant and ancient fish to our rivers--Matt Miller

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