Center for Biological Diversity

For Immediate Release, July 6, 2021


Taylor McKinnon, (801) 300-2414,

U.S. Fish and Wildlife Service to Reduce Razorback Sucker Protection Despite Lack of Successful Reproduction, Drying Colorado River

Razorback Populations Still Reliant on Hatchery-Raised Fish

DENVER— The U.S. Fish and Wildlife Service today proposed to reduce protection for a fish called the razorback sucker by reclassifying it from endangered to threatened under the Endangered Species Act. The move comes despite threats to the fish’s wild populations and despite dire forecasts for worsening climate-driven declines in Colorado River flows. The fish, which can grow up to 3 feet long and live for 40 years, is threatened by population fragmentation by dams, predation by non-native fish, altered river flows and climate change.

“With almost zero wild-spawned fish surviving to adulthood, today’s rule ignores basic biology,” said Taylor McKinnon at the Center for Biological Diversity. “Razorback suckers are still dangerously imperiled. And that situation’s made worse by the Colorado River Basin’s grim climate future.”

The recovery plan for razorback suckers requires the number of fish hatched in the wild to equal or exceed adult mortality before the species’ status can be changed from endangered to threatened. This recovery plan requirement has not been met, largely because non-native fish eat so many juvenile suckers that almost none make it to adulthood.

Recovery efforts rely on stocking hatchery-raised fish to bolster populations in the Upper Basin. Stocking maintains seven of the eight remaining populations, and only one — the Lake Mead population — exhibits natural recruitment and stability.

The proposed rule comes as the U.S. Southwest faces its worst drought in 500 years, driven by hotter temperatures that are sharply reducing river flows. Colorado River flows have already declined by 19% and are forecast to decline by 30% to 50% by mid-century and century’s end, respectively. Water availability is critical to ensuring spring floods and summer base flows that are necessary for razorback sucker reproduction and survival.

“Each dollar wasted on this downlisting effort is a dollar taken away from actual recovery,” said McKinnon. “In the face of a quickly worsening climate crisis in the Colorado River Basin, it’s troubling to see the Service touting more progress than really exists for a fish that’s in dire need of help.”

Razorback sucker photo by Sam Stukel, USFWS. Image is available for media use.

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 1.7 million members and online activists dedicated to the protection of endangered species and wild places.

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