Bats of the United States and Canada

Yuma Bat, Myotis yumanensis

184 bats of the united states and canada YUMA BAT (Yuma Myotis) Myotis yumanensis Special Concern–United States Weight is 4-6 grams (0.1–0.2 ounce); wingspan is 22–24 centimeters (9 inches); distribution is from southwestern British Columbia, through the western United States, and into central Mexico. From the cottonwood-lined streams of the southwestern deserts to the redwood canyons of the Pacific coast, nearly all habitats of the Yuma bat show a common feature, the presence of open water nearby. It often is in areas without trees. Although locally abundant, the species seems to be absent in many apparently suitable feeding areas. The Yuma bat emerges when it is nearly dark and forages just above the surface of streams and ponds. Night roosts often show little or no evidence of use, but careful searching of abandoned cabins , attics, porches, and similar sites usually will reveal guano. In late May and early June, large nursery colonies may form in buildings, caves, mines, or under bridges. As with many other bats, males take no part in care of the young and usually are not found near nursery roosts. Instead, adult males generally scatter and lead somewhat solitary lifestyles. Nursery roosts are quickly abandoned if disturbed. Nursery roosts are vacated in autumn, although the migration destination of the bats is unknown. Diet includes beetles and relatively soft-bodied insects such as flies, termites, moths, and mayflies. One baby is born in late May or in June. Females give birth for the first time in the summer following their own birth. The Yuma bat has been proposed for listing as threatened or endangered. recto runninghead 185 This page intentionally left blank ...