Colorado River Chubs Won't Receive Federal Protection as Seperate Species

Apr 6, 2017

The U.S. Fish and Wildlife Service decided today not to list two Colorado River Basin minnows under the Endangered Species Act. Arizona Public Radio’s Melissa Sevigny reports.

Roundtail chub from Fossil Creek, 2005
Credit U.S. Fish and Wildlife Service


The agency proposed listing the headwater chub and roundtail chub as ‘threatened’ in 2015. It’s now withdrawn that proposal due to evidence the two fish are the same species—along with a third fish, the Gila chub.

Steve Spangle of the U.S. Fish and Wildlife Service says the agency will conduct an assessment of threats to the newly combined species.  "If the result of that species status assessment indicates that listing may be warranted, we could go through the process again, essentially starting over," he says.

Some dispute the finding the fish are all one species. Arizona fish biologist Robert Clarkson says the scientific literature shows they’re genetically distinct. "By lumping these species and missing this true diversity, you may mask or may not be able to determine localized threats to the species, and therefore may miss management opportunities to protect them," he says.

The formerly recognized Gila chub is already listed as endangered. It will remain protected as a separate species until the Fish and Wildlife Service reevaluates its status.