They have weathered volcanic eruptions and
landslides, seen woolly mammoths come and go and outlived the
dinosaurs. Now the Pacific Northwest’s white sturgeon are enduring
the scrutiny of scientists who want to understand more about North
America’s largest fish.
The scientists working
for Washington and Oregon have been tagging white sturgeon in the
Columbia River as part of a $2 million-a-year study financed by the
Bonneville Power Administration. Researchers have been asked to
learn how hydroelectric systems can be improved to allow for
healthier sturgeon populations.
So far, says team
member Mike Parsley, “we have dispelled all the myths.” One myth
was that the fish, which can live for 100 years, spawn in deep,
slow pools. Scientists now agree that sturgeon need rapids for
successful spawning runs.
Below the Bonneville
Dam, where rapids create ideal fast-water spawning conditions, the
Columbia hosts the world’s greatest sturgeon fishery, where over 1
million sturgeon are believed to thrive. But above the dam, where
the rapids give way to reservoirs and pools, spawning conditions
are limited. “The dams essentially trap the sturgeon in
reservoirs,” said John DeVore of the Washington Department of Fish
and Wildlife.
DeVore hopes the study, expected to
continue until 2001, will lead to the creation of fish-locks, since
at 1,500-pound maximum weight, sturgeon are too big to leap up fish
ladders. DeVore says the locks would help spawning sturgeon
navigate around Bonneville Dam and lead to a more dispersed
sturgeon population.
*Jamie
Murray
This article appeared in the print edition of the magazine with the headline New facts about old fish.
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