The Latest: Update on the endangered Pallid Sturgeon

Scientists found that dams are indeed to blame for population declines.

  • A 2-year-old pallid sturgeon.

    Katie Steiger-Meister/USFWS
 

BACKSTORY
In 1990, “the dinosaur of the Missouri River,” the pallid sturgeon, was declared endangered. Scientists blamed dams on the Upper Missouri, but lacked proof. Meanwhile, they’ve released thousands of hatchery-raised sturgeon to bolster population numbers. In recent years, a few wild fish have been discovered, but live offspring appear to be lacking (“Can pallid sturgeon hang on in the overworked Missouri River?HCN, 9/24/12).

FOLLOWUP
In January, a study from the U.S. Geological Survey and University of Montana researchers proved that the dams cause reduced oxygen levels, decreasing sturgeon embryos’ odds of survival. Another discovery was more encouraging: Genetic testing just confirmed that two fish larvae, found last June in the Missouri near St. Louis, were wild pallids. It was the first time the species has turned up in that stretch at such early stages of development — a sign that, despite the dams, some natural reproduction is occurring.