The U.S. Fish and Wildlife Service (“Service”) published a proposed rule (PDF) this week to reclassify the spikedace and loach minnows from threatened to endangered under the federal Endangered Species Act (“ESA”). The proposed rule also designates approximately 796 miles of streams and rivers in central and eastern Arizona and western New Mexico as critical habitat for the two fish.

Both the spikedace and the loach minnow are small fish that measure fewer than three inches in length. They inhabit shallow water in perennial streams. According to the Service, prolonged drought, anticipated effects of climate change, increasing abundance, and the expanding range of competitive and predatory nonnative fishes have increased the threat of extinction for both species. The proposed re-designation of critical habitat is the result of court challenges and a General Inspector audit of the 2007 rule. As for the reclassification, the Service had actually determined that listing the species as endangered was warranted in 1994, but reclassification was precluded by other higher priority listing actions.

The original listing rules, 2007 critical habitat rule, current habitat proposal, and recovery maps are available on the Service’s website. The public may submit comments on the proposed rule and relevant scientific and commercial information to the Service until December 27, 2010.