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Sturgeon
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Sturgeon

Researchers catch shortnose sturgeon in the Savannah River and implant tracking devices to follow the movements of the endangered fish. The shortnose sturgeon has survived as a species for more than 100 million years, but is now threatened because of incompatible dam management.
© Andrew Tucker

Travels of a Sturgeon: Tracking Fish to Guide a River Restoration

By Christine Mlot

On a cold moonlit night last March, researchers cast off into the Savannah River in Georgia in search of endangered shortnose sturgeon. Since 2004, The Nature Conservancy has been working with the Army Corps of Engineers to help restore the river by periodically releasing water from the J. Strom Thurmond Dam. The releases mimic seasonal floods that once nourished downstream floodplains and served as cues for sturgeon and other migratory fish.

Conservancy and state biologists netted four sturgeon and implanted transmitters to track whether the fish were able to use the water release to swim past an old lock and dam to reach upstream spawning grounds. Surprisingly, they headed downstream instead of up, perhaps because the release of cold water from the bottom of the reservoir cued the fish that conditions were not right for spawning, says Amanda Wrona, director of the Conservancy’s Savannah River Project. “It may indicate the need for a fish passage or removal of the lock and dam,” she says.

The researchers also learned that one intrepid sturgeon traveled more than 300 miles in a week to the Santee-Cooper river system near Charleston, South Carolina. “That was really unusual,” says Wrona, and might indicate that the Savannah sturgeon are a source of genetic diversity for other systems. “That’s another reason not to let this population go.”

Learn more

• About the Conservancy's Sustainable Waters Program
• About our work in Georgia