This species was common in the spring and autumn of 1951 from the lower
edge of the yellow pine forest down into the belt of Joshua trees. In
early April on the desert slope at 4800 feet in Mescal Canyon,
pipistrelles foraged on evenings when it was windy but not cold. On cold
evenings (when the temperature was below roughly 45 deg.F) none was seen. On
windy nights the pipistrelles often forsook their usual high forage
habits and foraged 15 feet or so above the ground where the vegetation
and outcrops of rock broke the force of the wind. In 1951 no
pipistrelles were noted on the desert slope later than October 15.
_Specimens examined._--Los Angeles County: Mescal Canyon, 4800
ft., 4.
=Eptesicus fuscus bernardinus= Rhoads