Even a big fish needs to be held sometimes. Army engineers in Oregon saw a big blip on their sonar readings near the Bonneville Dam on the Columbia River, which they assumed to be a pile of debris. Instead of junk, they found sturgeon. About 60,000 of them had gathered in a huge congregation 40 to 50 feet below the surface of the river, and U.S. Geological Service biologist Michael Parsley said his estimate could be on the conservative side. In an undersea cuddle party, these fish lie on top of one another, some of them upside down. Army divers took this video of the gathering. The fish, which can grow as long as 14 feet, seem pretty happy with their situation, but biologists have little idea why they do it -- for all the worries about salmon, another resident of the Columbia, fewer people study sturgeon, so they remain ...
Sixty Thousand Sturgeon Have a Group Hug in Oregon
Discover the surprising Bonneville Dam sturgeon gathering of 60,000 fish on the Columbia River and the mystery behind their behavior.
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