FWS revises ESA listing for Preble’s mouse

Posted by egable on July 9th, 2008 filed in Endangered species

The Fish and Wildlife Service has removed Endangered Species Act protection for Preble’s meadow jumping mouse populations in Wyoming but retained a “threatened” listing for the subspecies in the Colorado portion of its range, FWS officials announced today.

The service also determined that Preble’s meadow jumping mouse is a valid subspecies eligible for protection under ESA. Preble’s geographic isolation from other subspecies of meadow jumping mice led it to develop considerable genetic differences from those other subspecies, FWS officials said.

At the time Preble’s meadow jumping mouse was added to the federal list of threatened and endangered species, it was known only to occur in a few sites in Wyoming.  Since then, additional data have shown that Preble’s populations occur throughout the North Platte River Basin in Wyoming.

Land use across Preble’s habitat in Wyoming is dominated by agriculture, mostly haying and grazing. FWS found that continuation of these long-standing activities does not appear to pose a threat to existing Preble’s populations. In addition, FWS said there is no indication that these agricultural practices are likely to change in the foreseeable future in ways that would affect Preble’s populations.

The main threat to Preble’s populations in Colorado is projected human population growth along the Front Range, but the service said human development in Wyoming is not expected to occur at a pace or level that would impair Preble’s populations there.

Additional sites supporting Preble’s meadow jumping mouse have also been identified in Colorado, but more than 80 percent of Colorado trapping efforts targeting Preble’s have failed to capture any individuals of the species. These results suggest that the subspecies is rare or extirpated from many portions of its historical range in Colorado, FWS officials said.

In much of the Preble’s range in Colorado, development activities have severely altered or destroyed its habitat, a trend that is expected to continue, FWS said. Without the protection of the Endangered Species Act, the service expects that most of the remaining habitat would be lost or altered within the foreseeable future.

The Preble’s meadow jumping mouse is a small mammal with a long tail, large hind feet and long hind legs. An adult can reach 7 to 10 inches long, with the tail comprising approximately 60 percent of that length.  To evade predators, the mouse can jump up to three feet.

It inhabits well-developed plains riparian vegetation with relatively undisturbed grassland communities and a nearby water source. It has been found to use uplands as far out as 100 meters beyond the 100-year flood plain.