Two May-taken females had enlarged uteri and one taken on July 8 was lactating. The testes of a May-taken male measured 5, whereas those of one obtained in early July measured 9. One of two males shot on August 4 was a young of the year; the other, an adult, was in fresh pelage as was an adult male shot on July 8. The July-taken lactating female and three June-taken specimens were in old pelage. Several specimens were parasitized on the ears by chiggers, Leptotrombidium myotis (Ewing).
Lasiurus cinereus cinereus (Palisot de Beauvois, 1796)
Hoary Bat
The hoary bat seemingly is an uncommon summer resident of Harding County as but one specimen, a non-pregnant female, has been taken there. This bat was shot on the evening of June 22, 1961, in the Slim Buttes as it foraged over a small pond in Deer Draw (10 mi. S and 5 mi. W Reva).
Plecotus townsendii pallescens (Miller, 1897)
Townsend's Big-eared Bat
Specimens examined (4).—2 mi. S, 3-1/4 mi. W Ludlow (Ludlow Cave), 2 (1 SDSU); 10 mi. S, 5 mi. W Reva, 2.
This big-eared bat evidently is uncommon in northwestern South Dakota. Of the four specimens examined, two were taken at Ludlow Cave and two were taken in June in the southern part of Slim Buttes—a female shot as it foraged over a pond in Deer Draw and another female netted over a water tank at Summit Spring about a half mile south of Deer Draw.
Ludlow Cave, in the caprock on the southeastern edge of the North Cave Hills, was formed by water erosion, resulting in numerous pockets and crevises in the ceiling and walls. The cave faces northwest; the mouth measures approximately 10 feet in diameter. A few feet from the entrance the cave narrows and approximately 50 feet back it is no more than three feet in diameter, although in the first 30 feet or so the ceiling varies from 10 to 15 feet in height. A thorough search of this cave on June 18, 1961, revealed one bat, a male Plecotus, which was shot from the ceiling about 15 feet from the entrance. No bats were found when the cave was visited on May 16 and again on June 4, 1968. Visher (1914:92) reported that several Plecotus were found there in early September, 1912. Probably Ludlow Cave, along with the several abandoned coal mines in the county, serves as a hibernaculum for some species of bats.