V. Rick McDaniel

FURTHER EXTENSION OF THE RANGE OF THE NORTHERN PYGMY MOUSE, BAIOMYS TAYLORI, IN SOUTHWESTERN OKLAHOMA

The range of the northern pygmy mouse (Baiomys taylori) has been expanding northward and westward in Texas (Austin and Kitchens, 1986; Hollander et al., 1987), across the Red River in the panhandle of Texas (Cleveland, 1986), and into southwestern Oklahoma (Stangl and Dalquest, 1986; Caire, 1991). Caire (1991) argued that recent mild winters could be responsible for the establishment of a breeding population in southwestern Oklahoma because Stangl and Dalquest (1986) and Stangl and Kasper (1987) indicated that periods of drought or subfreezing temperatures might periodically reduce or eliminate resident Oklahoma populations. Prior to the collections reported here, the known specimens from Oklahoma included a male from Cotton Co.

Hibernating Indiana Bats (Myotis sodalis) from the Ouachita Mountains of Southeastern Oklahoma

homa by Heath et al. (1986), Stevenson (1986), Saugey et al. (1989), and W. Caire (in litt.) have not yielded this species. On 16 January 1989, a hibernating cluster of seven Indiana bats was discovered in Bear Den Caves, LeFlore Co., Oklahoma. The cluster, composed of both sexes, included a single male Myotis lucifugus and was located about 6 m above the cave floor. Air temperature was 9.50C within a meter of the bats. The cluster was located in a

A broadband ultrasonic field detector for monitoring bat cries.

? 1951b. The status of the manatee in the Everglades National Park, with notes on its natural history. J. Mammal. 32:22-36. . 1956. Observations of manatees in aggregations. Am. Mus. Novit. 1811:1-24. NELSON, L. J., AND J. M. PEEK. 1982. Effect of survival and fecundity on rate of increase in elk. J. Wildl. Manage. 46:535-540. ODELL, D. K., AND J. E. REYNOLDS. 1979. Observations on manatee mortality in south Florida. J. Wildl. Manage. 43:572-577. POWELL, J. A., AND G. B. RATHBUN. 1984. Distribution and abundance of manatees along the northern coast of the Gulf of Mexico. Northeast Gulf Sci. 7:1-28. ROBINETTE, W. L., J. S. GASHWILER, J. B. Low, AND D. A. JONES. 1957. Differential mortality by sex and age among mule deer. J. Wildl. Manage. 21:1-16.

INTRASPECIFIC VARIATION WITHIN A SOUTHEASTERN POPULATION OF THE PRAIRIE VOLE, MICROTUS OCHROGASTER (RODENTIA)

Intraspecific variation in the prairie vole, Microtus ochrogaster, was examined using univariate and multivariate statistical techniques. Twelve morphological characters of 271 specimens collected from 15 quadrats in Arkansas, Missouri and Tennessee were utilized in data analyses. A matrix of correlation of characters was computed and the first three principal components, accounting for 91.1% of the character set variation, are reported. Projections of quadrat samples onto the first three principal components revealed interlocality variability within morphological characters. A general trend for voles being largest in the southern localities and smallest in the northern localities was identified. In addition, significant nonsize differences were noted between voles from localities east of the Mississippi River and those west of the Mississippi. No evidence was found to support the hypothesis of a disjunct central Arkansas population. The prairie vole, Microtus ochrogaster (Wagner), is a widely distributed microtine of the central United States. In the southeast its range includes much of northern and eastern Arkansas and western Tennessee (Hall, 1981). Southern expansion of this species appears to have been rapid and since 1959 it has advanced into south-central Arkansas and across Tennessee into Alabama (Severinghaus, 1976). Sealander et al. (1975) investigated the central Arkansas population of M. ochrogaster and concluded that a disjunct population in the vicinity of Little Rock had morphologically diverged from more northern populations. The purpose of this study was to examine intraspecific variation of cranial characters across the ranges of M. ochrogaster in southeast Missouri, Arkansas and west Tennessee.