DECLINE OF THE MEADOW JUMPING MOUSE (ZAPUS HUDSONIUS LUTEUS) IN TWO MOUNTAIN RANGES IN NEW MEXICO

The New Mexico meadow jumping mouse (Zapas hudsonius luteus) is endemic to riparian habitats in the American Southwest. We evaluated current status and habitat of this species in the Jemez and Sacramento mountains, New Mexico. We complied historical capture localities and conducted field surveys at historical and potential new localities hiring 2005 and 2006. We did not find the species or its habitat at 73% of historical localities surveyed in the Jemez Mountains and 94% of historical localities surveyed in the Sacramento Mountains. It persisted in two drainages (five localities) in the Jemez Mountains and two small, isolated localities in the Sacramento Mountains. Zapus h. luteus was associated wit-h tall, dense, herbaceous riparian vegetation, especially areas dominated by sedges. The lower bound to the 95% confidence interval for vertical cover at localities where Z. h. luteus was captured was 63 cm. Decline in distribution was clue to loss of this habitat, primarily as a result of livestock grazing. However, drought development, recreation, forest fire, and loss of the American beaver (Castor canadensis) also contributed. We recommended that conservation of Z. h. luteus will require establishment of refugial areas of suitable habitat through protection front livestock grazing.