A prehistoric fish that once thrived throughout the
Missouri and Mississippi rivers is teetering on the brink of
extinction. Only 250 wild pallid sturgeons remain in the upper
Missouri River of Montana and North Dakota, and they are growing
old. Each of these fish is between 40 and 50 years
old.
“Most of those are probably going to die out
in the next decade or so,” says Al Sapa of the U.S. Fish and
Wildlife Service in North Dakota.
The pallid
sturgeon is a peculiar-looking fish with a skin of bony plates; it
can weigh as much as 80 pounds. Its habitat of silty backwater has
largely disappeared behind six mainstem dams built by the U.S. Army
Corps of Engineers on the Missouri River. The Corps also lined many
miles of free-flowing river stretches with rock riprap, which wiped
out the beaches and sandbars that provide backwater
habitat.
The U.S. Fish and Wildlife Service is
focusing its pallid sturgeon recovery efforts on the Yellowstone
River, a tributary that still flows free through mostly natural,
braided channels. Earlier this month, the agency released more than
1,000 year-old, captive-bred fish into the Yellowstone and Missouri
rivers in North Dakota and Montana. A Fish and Wildlife Service
recovery plan aims to restore the fish by the year
2040.
In addition to fish stocking, Sapa says,
the sturgeons will be helped by restoring river habitat and by
releasing water from dams to recreate high spring flows. The new
habitat and more natural river flows, could improve life for other
species as well, including the sturgeon chub, sicklefin chub and
paddlefish. Two bird species, the endangered least tern and the
threatened piping plover, nest on sandbars that are often flooded
by unnatural water releases from the dams.
*Dustin Solberg
This article appeared in the print edition of the magazine with the headline Back from the brink.
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