Searching for Pocket Mice in the San Luis Valley

The Rio Grande National Forest is revising their 1996 Forest Management Plan. The Forest Management Plan is the guiding document for all management decisions and activities on the Rio Grand National Forest. As part of the update, Rio Grande NF staff are seeking more information on rare species. This summer, the Rio Grande hired CNHP zoologist Rob Schorr to survey for several lesser-known and rare small mammals. Two of the primary targets were the silky pocket mouse (Perognathus flavus sanluisi) and the plains pocket mouse (Perognathus flavescens relictus), both of which are unique to the valley. These pocket mice prefer the sandy soils of the San Luis Valley. Schorr and his daughter spent time trapping for the pocket mice on US Forest Service lands north of Great Sand Dunes National Park. They trapped in eight different areas, catching one silky pocket mouse and two plains pocket mice in sandy, sparse grasslands below pinyon and juniper forests.

The plains pocket mouse capture site with sandy soils, tall grasses, and rabbitbrush (Chrysothamnus spp.).

A close-up of a plains pocket mouse.

One of the two plains pocket mice captured on Rio Grande National Forest lands in 2015. 

The silky pocket mouse capture site on the Rio Grand National Forest. The site has sandy soils and large patches of blue grama (Bouteloua gracilis).