HARVARD UNIVERSITY Library of the Museum of Comparative Zoology . ,, MUS. COMP. ZOOll ^ ^ ' LlBRARYi OCCASIONAL PAPERS JUL ® 1974 HARVARD yNiveRSi'Pfi MUSEUM OF NATURAL HISTORY of the The University of Kansas Lawrence, Kansas NUMBER 25, PAGES 1-39 JUNE 17, 1974 THE MAMMALS OF CARTER COUNTY, SOUTHEASTERN MONTANA By Richard P. Lampe,^ J. Knox Jones Jr.," Robert S. Hoffmann,^ and Elmer C. Birney^ This report treats the more than 50 species of mammals occurring in a segment of the Northern Great Plains defined by the political boundaries of Carter County, Montana, the southeasternmost county in the state. The mammalian fauna of this area has, until now, been relatively poorly documented. Carter County (Fig. 1), organized in 1917 and named after Thomas Henry Carter, Montana's fii^st Congressional representative, has an area of approximately 3300 square miles and slopes north- eastward on the average at 10 feet to the mile (Bauer, 1924:233). The county is characterized by gently rolling hills, extensive flats, steep ridges, and occasional "badlands." The Boxelder Creek Valley drains northeastward through the center of the county. This valley varies in elevation from 3200 to 3500 feet above sea level and gener- ally is featureless except for the intermittent tributaries of Boxelder Creek that flow either northwestward or southeastward. The north- ern portion of the valley, referred to as Alkali Flats, is bordered by ^ Bell Museum of Natural History, University of Minnesota, Minneapolis, 55455. Tliis paper is based in part on research accomplished wliile the senior author was a graduate student at the Museum of Natmal History and Depart- ment of Systematics and Ecology, The University of Kansas. ^ Associate Vice President for Research and Dean of the Graduate School, Texas Tech University, Lubbock, 79409 ^ Curator of Mammals, and Professor of Systematics and Ecology, Museum of Natural History, The University of Kansas, Lawrence, 66045 * Curator of Mammals, Bell Museum of Natural History, University of Minnesota, Minneapolis, 55455 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY 45° 30 I04°30 MEDICINE ROCKS ^^ PINIELE EKAL^KA a MILL IRON- EKALAKA HILLS CHALK BUTTES LONG -^^ • PINE HILLS 45° 30 CAPITOL? / 0 10 MILES 1 04° 30 / ^V •ALBION >ALZADA Fig. 1. Map of Carter County, Montana, showing location of place-names mentioned in text. Camp Crook, Harding Co., South Dakota, is located at the black dot on the right-hand margin of the map. THE MAMMALS OF CARTER COUNTY. MONTANA 3 three disjunct pine-clad ridges, Chalk Buttes to the west ( maximum elevation, 4215), Ekalaka Hills to the north (maximum elevation, 4115), and Long Pine Hills to the east (maximum elevation, 4130). The Long Pine Hills and Ekalaka Hills are separated by Boxelder Creek, whereas the latter and Chalk Buttes are separated by a small valley drained by the intermittent Little Beaver Creek. Little Beaver and Boxelder creeks are tributaries of the Little Missouri River, which traverses the southeastern corner of the county. The extreme western part of the county lies in the Powder River drainage. Largest of the three pine-clad ridges are the L-shaped Long Pine Hills, which extend north and south for approximately 18 miles with an east- west base of 11 miles. Lillegraven (1970:832) de- scribed the Long Pine Hills as part of a s\'stem of ". . . Tertiary erosional remnants standing above the Late Cretaceous rocks of northwestern South Dakota, southwestern North Dakota, and south- eastern Montana." The southern and western sides of these ridges tend to have more cliffs and support less vegetation than do the eastern and northern slopes, which slope gradually onto the plains (Bauer, 1924:233; Lillegraven, 1970:832). Landslides of Tertiary rocks in the Long Pine Hills and Finger Buttes have been part of the erosional sequence of the area (Gill, 1962:731). South of Boxelder Creek Valley, the roHing landscape is broken by numerous, sparsely vegetated buttes. Formations such as Chim- ney Butte, Sheep Mountains, and Finger Buttes extend as a chain southwestvvard from the Long Pine Hills, forming the divide be- tween the drainages of Boxelder Creek and the Little Missouri River. Soils of Carter County are of four t\'pes (Kellogg, 1938). Chest- nut soils of the Williams-Morton-Bainville series have developed over glacial tills, sandstone, and shale and are found in the northern and southwestern parts of the county. In the extreme northwestern corner, brown soils have developed over shale and sandstone. Litho- sols of the Pierre type, with parent material of Cretaceous shale, occur in southeastern Carter Count}'. The rough, eroded areas or "badlands" of the north-central part of the county have developed over clay and shale of Tertiary formation. Banks and washes of the many dry stream beds found throughout the count\' are sandy. Underhing or partial!)' exposed sedimentary rocks of Cretaceous deposits include Benton (shale), Niobrara (shale), Pierre (shale), and Fox Hill (sandstone). Tertiary deposits include the Ludlow and Hell Creek members of the Lance formation, the Tongue River member of the Fort Union formation, the White River formation, and the Arikaree fomiation ( Bauer, 1924; for additional information on geologic formations see also Alden, 1932, and Perry, 1962 ) . Much of Carter County is covered by mixed-grass prairie, com- plemented by pine-clad ridges and sagebrush flats. Part of the SioiLX Division of Custer National Forest, the Chalk Buttes, Ekalaka Hills 4 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY (known also as the Ekalaka Forest), and Long Pine Hills support predominantly ponderosa pine (Pinus ponclerosa). Mature stands of this pine are relatively open; they usually are restricted to ridges and slopes, only seldom extending onto the grassy lower valleys that dissect the ridge formations. Northern and eastern slopes generally support denser stands than do southern and western slopes, which tend to be steeper and have more cliffs. Sawlog and pole stands generally accommodate an undcrstory of mixed grasses, forbs, and woody shrubs, whereas stands of saplings have a poorly developed understory in response to the greater density of young trees and consequent minimal sunlight penetration. Park-like stands of pine commonly occur on lower slopes and subordinate ridges along with snowberry (Symphoricarpos racemostis), various grasses, shrubs, and forbs. Juniper (Juniperus scopulonim) occurs irregularly and small stands of aspen (Popiilus tremiiloides) occupy some slopes. Thickets of common snowberry, fleshy hawthorne {Crataegus sp. ), wild plum (Priinus sp. ), chokecherry (P. melanocarpa), buf- falo-berry (Shepherd ia sp.), gooseberry and currant (Rihes sp. ), serviceberry (Amelanchier alnifolia), and rose (Rosa sp.) occupy some of the wetter ravines. Boxelder (Acer negundo), green ash (Fraxiniis pennsylvanica), and some ponderosa pine are found in the drainageways leading from the ridges. The grassland drainages sup- port discontinuous stands of deciduous trees — mainly cottonwood (Popidus sargentii), willow ( Salix sp. ) , boxelder, and green ash — characterized as the Northern Floodplain Forest (Kiichler, 1964); the Little Missouri River is lined with a heavier growth of riparian forest than that found along smaller streams throughout the county. Grasslands of the county are of the wheatgrass-needle grass com- munity (Kiichler, 1964) with dominants of western wheatgrass (Agropyron smithii), blue grama (Bouteloua gracilis), needle-and- thread grass (Stipa comata), and green needle-grass (Stipa viridula). Grasslands occupying the valleys and meadows of the Long Pine Hills are characterized as a sedge-blue grama-bluestem-wheatgrass community (Jonas, 1966:7) but ". . . under more favorable condi- tions needle-and-thread grass would possibly replace wheatgrass in importance." Flats in the northern and central areas of the county are commonly vegetated by fringed sagebrush (Artemisia frigida), big sagebrush (A. tridentata), and silver sagebrush (A. cana), with an understory of short grasses and prickly pear (Opuntia humifusa). Carter County has a semiarid continental climate (Table 1) that is shielded from the northward flow of precipitation-laden air by the Black Hills. Slightly more than half of the mean annual precipi- tation falls in May, June, and July. Seasonal fluctuation in temper- ature is great and fluctuations are common from day to day. The contrast between summer and winter temperatures is exemplified by an average of 34 days with a maximum temperature above 90° F and THE MAMMALS OF CARTER COUNTY, MONTANA 5 Table 1. Climatological data from Ekakka, Montana (1931-1952), and Camp Crook, South Dakota (1896-1967). Temperature is recorded in degrees Fahr- enheit and precipitation is measured in inches. Ekalaka, Montana Camp Crook, South Dakota Temperature Mean annual 44.1 43.8 Mean January 17.6 17.3 Mean July 71.8 71.2 Record high 108 114 Record low -43 -57 Precipitation Mean annual 13.27 13.71 Record maximum 21.97 (1963) 24.07 (1927) Record minimum 6.35(1936) 4.73(1936) Mean annual snowfall 22.3 33.2 an average of 33 days with a minimum temperature below zero. During winter, prevailing northwest winds often accompany snow storms, creating drifts in protected areas and leaving open fields bare. It is noteworthy that weather- conditions in July, 1972, were unseasonably cold and wet, including temperatures below 32°F and freezing rains. Our interest in the mammals of Carter County stemmed from studies by one of us (Jones) conducted in Harding County, South Dakota, during the 1960's as well as pre\ ions work in Montana by Hoffmann. Kenneth Andersen visited the Long Pine Hills briefly in May of 1968 and obtaincxl a small collection of mammals. Subse- quently, in the period 29 June to 24 July 1970, a field party from The University of Kansas made extensive collections from the Long Pine Hills and other localities in northern and eastern Carter Count)^ and Jaime Pefaur, a graduate student at The University of Kansas, studied populations of small mammals on a north-facing slope at the eastern edge of the Long Pine Hills until mid-August of the same year. Birney and Lampe collected mammals for the Uni- versity of Minnesota in the Long Pine Hills, Ekalaka Hills, and Chalk Buttes in July 1971. Merlin Tuttle and Larry Heaney made additional collections for Minnesota in Carter County in July 1972. Early reference to the mammals of Carter Count}' was made by Captain W. F. Reynolds (1S6(S) during his brief passage through the area in 1859. Subsequent military explorations in this area, such as General George Custer's expedition to the Black Hills in 1874, were concerned primarily with matters other than faunal observa- tions (see also Turner, 1974). E. A. Preble, in an undated manu- script, probably written about 1910, listed mammals from eastern Montana and briefl\- connnented on the habitat preference and abundance of 57 species. Other references in the literature to mam- mals of Carter County are those of Visher (1914), Couey (1946), 6 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY Tryon (1947), Hoffmann et ah (1969a,b), Andersen and Jones (1971), Pefauer and Hoffmann (1971), and Jones et al. (1973). Several specimens from Carter County liave been incorporated in revisionary studies sucli as tliose by Nelson (1909), Bailey (1915), Hollister (1916), Jackson (1928), Howell (1929, 1938), and Gold- man (1944). Acknowledgments We acknowledge the field assistance of the students who were enrolled in the Field Course in Vertebrate Zoology at The University of Kansas in the summer of 1970 as well as the members of several other field parties from Kansas who visited Carter Count)' periodi- cally. Merlin D. Tuttle and Lawrence R. Heaney collected mam- mals in Carter County for the University of Minnesota for 10 days in July of 1972. The summer field course was financed in part by grant GZ-1512 from the National Science Foundation. Minnesota field parties in both 1971 and 1972 were supported by grants to Birney from the Graduate School, University of Minnesota and from the Grassland Biome Section of the International Biological Program (NSF Grant GB-13096). We especially thank District Rangers T. S. Burns and Richard McElfresh and their staff for assistance and sincere interest in our study. We also wish to acknowledge the cooperation and hospitality shown our field parties by various U.S. Forest Service personnel (Sioux Division, Custer National Forest) and numerous residents of Carter County, Montana, and Harding County, South Dakota. Identifications of ectoparasites were provided by Drs. Eleanor K. Jones (ticks), J. M. Kinsella (fleas), Richard B. Loomis (chiggers), and Nixon Wilson ( mites ) . ACCOUNTS OF SPECIES The following accounts treat the 53 species of mammals pres- ently on record from Carter County, Montana. Additionally, com- ments on 15 species of unverified occurrence are appended. Speci- mens examined (a total of 488) are listed in telegraphic style and are ordered first from north to south and, secondarily, from west to east. All specimens examined are deposited in the Museum of Natural History at The University of Kansas or in the Bell Museum of Natural History at the University' of Minnesota (noted as MMNH). All measurements used are in millimeters (lengths of embryos are for crown-rump) and weights are expressed in grams. In certain cases, measurements are given as means, with extremes in parentheses. THE MAMMALS OF CARTER COUNTY, MONTANA 7 Order Insectr'ora Sorex cinereus haydeni Baird, 1858 Masked Shrew Specimens examined (26). — 3 mi S, 1.75 mi E Ekalaka, 6 (MMNH); 5.5 mi N, 10 mi W Camp Crook, 3500 ft, 20 (17 MMNH). The masked shrew evidently is a common inhabitant of pro- tected, mesic habitats in the pine-covered portions of tlie study area. Only three specimens, all adults, were captured during approxi- mately four weeks of intensive trapping in summer of 1970. Most trapping efforts were with break-back traps, although buried can traps were tried unsuccessfully in several areas in the Long Pine Hills that seemed suitable for shrews. Three additional specimens, two adult females and a shrew of unknown sex, were captured in 1971 in break-back traps in the mesic draw at Lantis Spring and in lush vegetation around a nearby bea\'er pond fed by the spring, the site of capture of two males in 1970. The third specimen from 1970, a female, was taken above the draw on snowbrush-covered ground near a clearing. On 10 July 1972, five can-traps were set near water at Lantis Spring. Four of these contained masked shrews the following morn- ing. Eleven more can-traps and 75 Museum Specials then were set in mesic habitat along the spring and near the beaver pond. No shrews were captured in the Museum Specials, but six more were taken from the cans. Even after an additional 50 Museum Specials, baited with a mixture of rolled oats and peanut butter, were set near the spring, all four shrews subsequently captured were taken from the 16 buried cans. A few days later, two Sorex were among the animals taken from 202 Museum Specials set in tall grass and reeds near a marsh in the Ekalaka Hills. Seventeen can-traps set near the marsh yielded four additional masked shrews. Brown (1967) and Spencer and Pettus (1966) demonstrated the efficiency of can-trapping for shrews. Our studies indicate that the masked shrew is not uncommon in Carter Countv'. Instead, it seems to be common in isolated or semi-isolated populations associated with permanent sources of water and relatively undisturbed habi- tats. Genoways and Jones (1972:5) trapped Sorex cinereus at seven localities in southwestern North Dakota, but Andersen and Jones (1971:388) did not report shrews from adjacent Harding County, South Dakota, although can-traps were not employed there. Three specimens from 5 mi SE Ekalaka were recorded by Jackson (1928: 53), and were probably those mentioned by Preble (MS) from the Sioux National Forest, near Ekalaka. Testes of 12 males taken in mid-July 1972 were 4 mm in mean length. One of eight females collected at that time carried four embryos, each 12 mm in length; another had placental scars but apparently had completed lactation. 8 OCCASION.\L PAPERS MUSEUM OF NATURAL HISTORY Sorex merriami leucogenys Osgood, 1909 Merriam Shrew Specimen examined ( 1 ). — 5 nii N, 3.5 nii W Camp Crook, 3400 ft, 1. Our specimen of Merriam's shrew, the fifth to be recorded from Montana (Pefaur and Hoffmann, 1971:247), was trapped on 22 July on a nortli-facing grassy slope at the eastern edge of the Long Pines. An adult male with enlarged flank glands and testes 5 mm in length, it had the following selected external and cranial measurements: total length, 101 mm; tail length, 39 mm; hind foot length, 11 mm; weight, 4.8 gms; condylobasal length, 16.5 mm; palatal length, 7.2 mm; cranial breadth, 8.3 mm; least interorbital breadth, 3.7 mm; maxillary breadth, 5.2 mm; maxillaiy toothrow length, 6.2 mm. Owing to the large size of this shrew, especially apparent in the cranial dimensions, we assign it to the subspecies leucogenys (see Long, 1965, and Hooper, 1944, for representative measurements of S. 772. leucogenys and S. m. merriami), even though the type locality of S. m. 7nerriot7ii lies only approximately 150 miles to the west. Order Chiroptera Seven species of bats were collected in Carter County in 1970. Collections were made principally in the Long Pine Hills, but a few bats were obtained in adjacent areas and at Medicine Rocks. Speci- mens obtained during that summer were reported by Jones et al. (1973) together with comments on habitat, reproduction, molt, ac- tivity, dietary habits, and ectoparasites of these seven bats. Included in the present accounts arc specimens obtained in the Long Pine Hills, Ekalaka Hills, and Chalk Buttes in 1971 and 1972. One spe- cies, Plecotus townsenclii, was not captured in Carter County until July 1972 and thus was not treated by Jones et al. ( 1973 ) . Myotis evotis evotis (H. Allen, 1864) Long-eared Myotis Specimens examined (7). — 4 mi S, 1 mi E Ekalaka, 4 (MMNH); 5.5 mi S, 1 mi E Ekalaka, 1 (MMNH); 7 mi N, 10 mi W Camp Crook, 3800 ft, 2 (MMNH). All Specimens are adults, and were netted over reservoirs in the Long Pine Hills and the Chalk Buttes and in a campground clearing in the Ekalaka Hills. At Stagville Spring, 4 mi S and 1 mi E Eka- laka, 11 long-eared myotis were collected over a spring-fed watering tank located in a brush-lined ravine. Seven of these were banded and released. Three of four banded females were lactating; the three males gave no external evidence of reproductive activity. Four adult males taken in mid-July had testes that were 3, 3, 4, and 5 mm in length, and three were in the process of seasonal molt. THE MAMMALS OF CARTER COUNTY, MONTANA 9 Myotis leibii ciliolabrum (Merriam, 1886) Small-footed Myotis Specimen examined (1). — 4 mi S, 1 mi E Ekalaka, 1 (MMNH). A lactating female in the process of seasonal molt was netted 18 July above a livestock tank in the Ekalaka Hills. This specimen is the only small-footed myotis known from the county outside of the Long Pine Hills, where six were obtained in 1970 (Jones et ah, 1973). Myotis lucifugus carissima Thomas, 1904 Little Brown Myotis No specimens of the little brown myotis were captured in 1971 or 1972. Jones et al. (1973) reported 12 individuals that had been netted or shot over water in the Long Pines in 1970. Myotis volans interior Miller, 1914 Long-legged Myotis Specimens examined (7). — 4 mi S, 1 mi E Ekalaka, 2 (MMNH); 5.5 mi S, 1 mi E Ekalaka, 3 (MMNH); 7 mi N, 10 mi W Camp Crook, 2 (MMNH). We found the long-legged myotis to be common in most areas of buttes and ridges in Carter Countv' although none was taken in the Chalk Ikittes. All specimens collected in mid-July are adults. One female was lactating and two males had testes that were 3 and 4 mm in length. Se\en adults were netted over a lixestock tank near Stag- ville Spring in the Ekalaka Hills on 17 Juh' 1971; of five subsetjuently banded and released, two were reproductively active females, one lactating and the other pregnant. Lasionycteris noctivagans (Le Conte, 1831) Silver-haired Bat Although found to be common in the Long Pine Hills in 1970 (Jones et al, 1973), only a single silver-haired bat was captured in the subsequent two summers. This specimen, an adult male netted over a beaver pond at Slick Creek Spring, 7 mi N, 10 mi W Camp Crook, was banded and released. Eptesicus fuscus pallidas Young, 1908 Big Brown Bat Specimens examined (4). — 11 mi S, 7.5 mi W Ekalaka, 1 (MMNH); 7 mi N, 10 mi W Camp Crook, 3800 ft, 3 (MMNH). Two adult male big brown bats were banded and released at the locality (Slick Creek Spring) listed above, and an additional two adult females and one adult male were preserved. An adult male (testes 8 mm in length) was netted ()\'er a small reservoir in the Chalk Buttes in 1971. We failed to capture this species in south- eastern Montana in 1972. 10 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY Lasiurus cinereus cinereus (Palisot de Beavois, 1796) Hoary Bat Specimens examined (6). — 4 mi S, 1 nii E Ekalaka, 1 (MMNH); 11 mi S, 7.5 mi W Ekalaka, 2 (MMNH); 7 mi N, 10 mi W Camp Crook, 3800 ft, 3 (MMNH). Volant juvenile hoary bats were netted in mid-July in both 1971 and 1972. Two adults, a lactating female and a male, also were cap- tured. Testes of the male were 8 mm in length on 13 July. One juvenile female was banded and released in the Long Pines in 1971. Plecotus townsendii pallescens (Miller, 1897) Townsend's Big-eared Bat Specimen examined (1). — 7 mi N, 10 mi W Camp Crook, 1 (MMNH). A reproductively inactive, adult female Plecotus was captured in a mist net stretched over a beaver pond in the Long Pine Hills on 12 July 1972. Preble ( MS ) reported the species from adjacent Powder River County and Hoffmann et ah (1969b: 741) considered it wide- spread in Montana. Andersen and Jones (1971:372) considered big- eared bats uncommon in Harding County, South Dakota. The ab- sence of this bat in our 1970 collections (Lampe, 1971; Jones et al., 1973) and in 1971 and the paucity of specimens from adjacent areas attest to the apparent rarity of the species in this portion of its range. Order Lagomorpha Lepus townsendii campanius Hollister, 1915 White-tailed Jackrabbit Specimens examined (9). — 12 mi E Ekalaka, 3200 ft, 1; 6.5 mi N, 5.5 mi W Camp Crook, 3400 ft, 1; 5.5 mi N, 3 mi W Camp Crook, 1; 2 mi N, 14 mi W Camp Crook, 1; 2 mi N, 4.5 mi W Camp Crook, 3700 ft, 1; 2.5 mi S, 3 mi W Camp Crook, 3200 ft, 1; 5.5 mi S, 3.5 mi W Camp Crook, 1; 6 mi S, 3 mi W Camp Crook, 3200 ft, 1; 12 mi S, 4 mi W Camp Crook, 1. White-tailed jackrabbits are common in the grasslands of Carter County, particularly in the meadows and broad valleys within the Long Pine Hills. All of our specimens were collected in 1970 from along roads or roadside ditches. An adult female taken on 3 July carried tlii'ee embryos, each of which was 48 mm in length. Another examined on 7 July was lac- tating; both females were actively molting. Three subadult males collected in early and mid- July had testes that were 24, 18, and 15 mm in length, whereas an adult male obtained on 5 July had testes 55 mm long. One jackrabbit was parasitized by ticks, Dennacentor andersoni. Sylvilagus audubonii baileyi (Merriam, 1897) Desert Cottontail Specimens examined (2). — 17 mi E Ekalaka, 3200 ft, 2. This cottontail was seen on sagebrush flats and in grasslands as THE MAMMALS OF CARTER COUNTY, MONTANA 11 well as on the pine-covered ridges of the Long Pine Hills. Two S. aiidtibonii were obtained from a small formation in the "badlands" north of the Long Pines. Preble (MS) listed specimens from the "head of Boxelder Creek," no doubt the same individuals reported by Nelson (1909:234) as simply from "Boxelder Creek." Addition- ally, Andersen and Jones (1971:373) reported a specimen obtained on a sparsely covered pine ridge at the extreme eastern edge of the Long Pines in Harding County, South Dakota. A subadult male examined on 8 July had testes 14 mm in length. An adult female shot on 9 July was actively molting and carried six embryos ( three in each uterine horn ) in addition to a seventh in the right uterine horn that, in light of its smaller size (9 mm in length as compared to 14 mm for the others), was apparently being re- sorbed. Sylvilagus floridanus similis Nelson, 1907 Eastern Cottontail Specimem examined (4). — 5.5 mi N, 10 mi W Camp Cronk, 1 (MMNH); 2 mi N, 4.5 mi W Camp Crook, 3700 ft, 1; 8 mi S, 3 mi W Camp Crook, 3200 ft, 2. The eastern cottontail occurs in Montana only in Carter County, where it is restricted to riparian habitats. One specimen was shot along a small spring-fed stream at the southeastern edge of the Long Pine Hills and a juvenile was trapped in a thicket on high ground at Lantis Spring; the other two \\'ere collected in dense, woody vege- tation along the Litde Missouri River. Hall and Kelson (1951:52) reported specimens of S. /. similis from Boxelder Creek (25 mi SW Sykes— Hall, 1951:159), Capitol, and the Little Missouri River (7 mi NE Albion — Hall, loc. cit. ) in southern Carter Count}-. It is of interest that our four specimens and those cited by Hall and Kelson (loc. cit.) all were collected in the eastern third of Carter County. The apparent absence of S. floridanus in western Carter County may be of importance with respect to the distribution of S. nutiaUii, which evidently has been displaced by S. -floridanus in ad- jacent states (Genoways and Jones, 1972:11; Turner, 1974:61). A female taken on 30 June carried six embryos. Two males shot in early July had testes 40 and 55 mm in length. These three speci- mens, all adults, were actively molting from winter to summer pelage. Order Rodentia Eutamias minimus pallidas (J. A. Allen, 1874) Least Chipmunk Specimens examined (15). — 17 mi E Ekalaka, 3200 ft, 1; 4 mi S, 1 mi E Ekalaka, 2 (MMNH); 4.5 mi S, 1 mi E Ekalaka, 2 (MMNH); 4 mi N, 8 mi W Camp Crook, 3650 ft, 4; 4 mi N, 7.5 mi W Camp Crook, 3800 ft, 1; 2 mi N, 4.5 mi W Camp Crook, 3700 ft, 3; 1.5 mi N, 5 mi W Camp Crook, 4100 ft, 2. 12 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY Chipmunks are common in the pine-covered hills of southeastern Montana. Specimens were obtained from ridges and roadsides where fallen logs and rocks provided suitable cover. Two adult males were collected at Capitol Rock, a large butte along the south- em edge of the Long Pine Hills, 1.5 mi N and 5 mi W Camp Crook, that is characterized by gullies, steep and eroded slopes, and pale- colored soils. An adult male obtained from a similar, but smaller area of "badlands" isolated in the grasslands of northeastern Carter County, 17 mi E Ekalaka, was markedly grayer than specimens col- lected in the Long Pines and Ekalaka Hills. This animal was actively molting on 8 July. A chipmunk was observed running over a bare, vertical cliff-facing at the crest of Trenk Pass, 11 mi S, 6.5 mi W Ekalaka, in July 1971, but no specimens were collected in the Chalk Buttes. An adult female obtained in late June and one taken in July were lactating and still retained winter pelage. Eleven subadults taken in July were molting. A young individual, one of four obtained on 25 July from 4 mi N and 8 mi W Camp Crook, had a scar, no doubt caused by a cuterebrid larva, on the right shoulder. Preble (MS) mentioned specimens from the Sioux National For- est and Alzada and commented tliat chipmunks inhabited "indiffer- ently the evergreen forests, bushy canyons, and even sections almost without forest cover. ..." Howell (1929:44) reported specimens from Alzada, Ekalaka, 8 mi E Svkes, and 5 mi E Svkes. Spermophilus tridecemlineatus pallidus J. A. Allen, 1874 Thirteen-lined Ground Squirrel Specimens examined (33). — 11.5 mi N, 3 mi E Ekalaka, 5; 16 mi E Eka- laka, 2; 1 mi S, 1 mi W Ekalaka, 1 (MMNH); 3.5 mi S, .25 mi W Ekalaka, 2 (MMNH); 3.75 mi S, 2.25 mi W Ekalaka, 3 (MMNH); 4 mi S, 1.5 mi W Ekalaka, 1 (MMNH); 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 18; 6 mi S, 4.5 mi W Camp Crook, 3200 ft, 1 . This ground squirrel is common in short grass and sagebrush throughout the area of study. Juveniles represented more than half of the total number of specimens obtained. Eight of eleven speci- mens collected in an upland meadow along the eastern edge of the Long Pine Hills during the period 8 to 13 July were ju\'eniles, and only one of seven individuals from southwest of Ekalaka was adult. Preble (MS) commented on the destruction of crops caused by thirteen-lined ground squirrels, "especially in the southeastern part of the state." Howell (1938:114) reported specimens from Albion, Capitol, and Medicine Rocks. An adult female taken on 14 July had seven placental scars and eight corpora albicantia. The testes of eight adult males obtained in mid-July had a mean length of 5.8 mm; those of eight juNcniles collected on comparable dates averaged 4.9. THE MAMMALS OF CARTER COUNTY, MONTANA 13 Fleas, Thrassis sp., and ticks, Ixodes sculptus, were found on these thirteen-lined ground squirrels. Cynomys ludovicianus ludovicianus (Ord, 1815) Black-tailed Prairie Dog Specimens examined (4). — 5 mi N, 6 mi E Ekalaka, 3400 ft, 3; 1 mi S, 13 mi E Ekalaka, 3200 ft, 1. Once a common inhabitant of grasslands throughout Carter County, the prairie dog was found in areas overgrazed by herds of bison and other ungulates. With the decline of native herbivore populations, the prairie dog became associated with domestic live- stock, often becoming a "pest," particularly in areas overgrazed by cattle and sheep. Visher (1914:89) reported the existence of large "towns" in Harding County, South Dakota, in the early 1900's, one of which covered "several sections . . . west of the Little Missouri River." Such colonies most likely occm-red also in Carter County. Rather than directly treating the cause of poor range condition, rodent control campaigns tended to treat only symptoms — that is, large populations of prairie dogs. The cflBciency of programs de- signed to eradicate this sciurid is attested to by the fact that Cyno- mys now occurs only in relatively small, disjunct populations in Carter County and adjacent regions. Three prairie dogs were shot in mid-day from a colony of approx- imately 200 individuals northeast of Ekalaka. The colony was lo- cated on flat ground covered with sagebrush (Artemesia tridentata), below the dam of a farm pond. Another specimen was obtained from a half-grown badger tliat was observed crossing a road with a prairie dog in its mouth. As members of our field party approached the badger, it dropped the prey and took shelter in a nearby burrow. Hollister (1916:14) reported a specimen from Boxelder Creek and Andersen and Jones (1971:375) noted two specimens from the grasslands of northwestern Harding County, South Dakota, border- ing the eastern Long Pine Hills. An adult female taken on 14 July contained eight placental scars and eight corpora albicantia. Two males, an adult and subadult, collected on 14 July both had testes 8 mm in length. Fleas, Opiso- crostis hirsuttis, and ticks, Ixodes kinp^i, were found on one of three individuals collected nortlieast of Ekalaka. Sciurus niger rufiventer E. Geoftroy St.-Hilaire, 1803 Fox Squirrel Specimens examined (2). — Sec. 16, T 5 S, R 62 E, 2. Although fox squirrels are known to occur in the riparian cotton- wood forests of the Yellowstone and Big Horn rivers in central Mon- tana (Hoffmann et ah, 1969a: 589), their presence in southeastern Montana has not been documented previously. Hibbard (1956:525) 14 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY discussed the westward spread of fox squirrels in North Dakota along the Missouri and James rivers as well as their wooded tribu- taries in the south-central part of that state. Our specimens verify the occurrence of fox squirrels in the Little Missouri drainage. Be- cause we know of no introductions of this species in tliis area of Montana, our records probably indicate a southward migration from the valley of the Missouri River. Both specimens are adult males in winter pelage, collected along the Little Missouri River in east-central Carter County on 14 Jan- uary 1971 by John Teigen, Jr. In this area, the banks and flood plain of the Little Missouri support riparian stands of boxelder, green ash, plains Cottonwood, and willows. Selected external and cranial measurements of our specimens are: total length, 490, 488 mm; tail length, 212, 208 mm; hind foot length, 68, 68 mm; ear length, 28, 28 mm; weight, 645, 623 gms; condylobasal length, 56.8, 58.8 mm; palatal length, 32.1, 32.5 mm; zygomatic breadth, 35.2, 35.2 mm; mastoid breadth, 27.6, 27.2 mm; postorbital breadth, 19.2, 19.1 mm; maxillary toothrow length, 11.4, 11.5 mm; testes length, 23, 25 mm. Tamiasciurus hudsonicus dakotensis (J. A. Allen, 1894) Red Squirrel Specimens examined (14). — 5.5 mi S, 1 mi E Ekalaka, 2 (MMNH); 7 mi N, 10 mi W Camp Crook, 3800 ft, 1; 6 mi N, 10 mi W Camp Crook, 1 (MMNH); 5.5 mi N, 10 mi W Camp Crook, 2 (MMNH); 4 mi N, 9 mi W Camp Crook, 3950 ft, 5; 3.75 mi N, 7.75 mi W Camp Crook, 2 (MMNH); sec. 1, T3S, R61E, 1. Red squirrels were collected in moderately dense stands of pon- derosa pine. Two were taken in the Ekalaka Hills in 1972 and others were collected in the central part of the Long Pine Hills in all three years of field work. Red squirrel "sign" was noted by Lampe and Birney in the Chalk Buttes, but no individuals were seen. Five squirrels were obtained in 1970 from an immature pine stand of 10 to 15 acres located on a gentle westward-facing slope marked by small ravines. Additional areas were hunted thoroughly, but only two other specimens were taken; a third was sighted 6 mi N and 10 iTii W Camp Crook. Three individuals were feeding on ponderosa pine cones when shot, but no indication of regular feeding stations was observed in 1970. Tliree red squirrels were shot and numerous others were seen during a two-day visit to the central Long Pine Hills in 1971. A midden with a surface area of approximately 60 square feet was found on a small north-facing slope at a place 8.5 mi N and 11 mi W Camp Crook. The midden was extremely moist as a result of its proximity to a nearby spring. Smaller caches and middens were seen elsewhere in the Long Pines around fallen and hollow trees. THE MAMMALS OF CARTER COUNTY, MONTANA 15 The scarcity of caches on the forest floor in stands of ponderosa pine was discussed by Finley (1969:238). The dryness of sites oc- cupied by this pine, the increased circulation of air and penetration of sunlight caused by the lack of lower limbs, and the open nature of stands create conditions unsuitable for the storage of cones. Caches seen in the Long Pines were associated with mesic or shel- tered conditions, whereas those observed in the Chalk Buttes were small, shallow subterranean chambers. The marked \'ariability in cone production of ponderosa pine (Finley, 1969:261) may account for much of the variation in red squirrel population density noted in the three years of our study. Preble (MS) mentioned that red squirrels were fairly common near Ekalaka and east of Sykes and that specimens from these places appeared to be typical T. h. dakotensis. Visher ( 1914:88) reported a specimen shot in the Long Pines in July of 1910, and Miller and Kellogg (1955:263) included southeastern Montana in the range of dakotensis. Andersen and Jones (1971:375) commented that speci- mens from the Long Pine Hills were clearh' assignable to dakotensis on the basis of color (see also Hoffmann and Jones, 1970:374, fig. 7; and Turner, 1974:80). Average (and extreme) external and cranial measurements of 12 adults (five females, seven males) are: total length, 343.4 (322-365) mm; tail length, 133.9 (115-144) mm; hind foot length, 53.9 (50-58) mm; ear length, 28.0 (25-30) mm; condylobasal length (four fe- males, seven males), 47.6 (46.7-49.1) mm; palatal length, 26.7 (26.0-27.3) mm; zygomatic breadth (four females, five males), 29.2 (28.9-30.4) mm; mastoid breadth (three females, six males), 24.1 (23.3-24.5) mm; postorbital breadth (four females, seven males) 14.2 (13.5-14.7) mm; maxillary toothrow length, 9.0 (8.8-9.2) mm. Five of seven females collected from late May through July were lactating; two contained three placental scars each. Two females obtained on 18 and 20 July were xoung of the year. Seven adult males taken during Julv had testes that had an average length of 14.2 (10-20) mm. Thomomys talpoides bullatus Bailey, 1914 Northern Pocket Gopher Specimens examined (34). — 16 nii E Ekalaka, 1; .5 mi S, 12 mi E Ekalaka, 1; 3 mi S, 1 mi E Ekalaka, 1 (MMNH); 3 mi S, 1.75 mi E Ekalaka, 3 (MxMNH); 12 mi S, 16 mi E Ekalaka, 3600 ft, 3; 8 mi N, 8 mi W Camp Crook, 2; 7 mi N, 3 mi W Camp Crook, 3400 ft, 1; 6 mi N, 10 mi W Camp Crook, 1; 6 mi N, 9 mi W Camp Crook, 4000 ft, 1; 5.5 mi N, 10 mi W Camp Crook, 1 (MMNH); 5.5 mi N, 9.5 mi W Camp Crook, 1; 5 mi N, 6 mi W Camp Crook, 3500 ft, 2; 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 12; 2 mi N, 4.5 mi W Camp Crook, 3700 ft, 1; 6 mi S, 4.5 mi W Camp Crook, 3200 ft, 3. The northern pocket gopher is common in Carter County. Our specimens were collected primaril)' in the Long Pine Hills from 16 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY roadside ditches, sparsely pine-clad ridges, and meadows. Four in- dividuals were trapped in similar habitats in the Ekalaka Hills and adjacent areas. Three were taken along a sandy arroyo located 6 mi S and 432 mi W Camp Crook, Bailey (1915:102) referred a specimen from Alzada to Thomo- inijs talpoides biillatus, the type locality of which is just to the west of Carter County at Powdemlle, Powder River County. Swenk (1941:3) later included this specimen in his description of T. t. pierreicolus, a subspecies supposedly delimited by the distribution of soils of the Pierre series. Andersen and Jones (1971:376) exam- ined a specimen from Harding County, also referred by Swenk (1941:3) to pierreicolus, and found it clearly referable to hullatus. Five adults collected in early and mid-July and a subadult taken in early July were molting. Two adult males obtained on 8 July had testes that were 10 and 13 mm in length, whereas those of a subadult taken the same day were 4 mm. An adult and a subadult collected on 18 July had testes that were 6 and 5 mm, respectively. An adult female taken on 8 July and two obtained 12 July contained, re- spectively, 13, 10, and six placental scars. The following ectoparasites were found on our specimens of Thomomys talpoides: a flea, Foxella ignota alhertensis; four mites, Amlrolaelaps geomys, Androlaelaps fahrenhoizi, Haemogamasiis sp., and Hirstionyssus sp.; two ticks, Ixodes kingi and 7. sculptiis; and two lice, Geomydoecus thomomiis and G. wardi. Fleas, mites, ticks and lice were found together on one specimen from the Long Pine Hills. Perognathus fasciatus olivaceogriseus Swenk, 1940 Olive-backed Pocket Mouse Specimens examined (30). — 11.5 mi N, 3 mi E Ekalaka, 1; 17 mi E Eka- laka, 3200 ft, 1; 4.5 mi S, 1 mi E Ekalaka, 1 (MMNH); 5.5 mi N, 3.5 mi W Camp Crook, 3400 ft, 22; 6 mi S, 4.5 mi W Camp Crook, 3200 ft, 5. The olive-backed pocket mouse was found to be common in grazed and ungrazed meadows on sandy soils. A series of 11 adults and 11 young was collected from a north- facing slope at the eastern edge of the Long Pine PI ills. Five individuals were obtained in an area of short grass and sage 6 mi S and 4.5 mi W Camp Crook, along a sandy arroyo. Specimens from 8 mi NE Albion were mentioned by Preble (MS). Adult females taken on 7 and 8 July carried embryos ( five meas- uring 11 mm and nine measuring 13 mm, respectively). A female bearing three placental scars was obtained on 9 July and one of two adult females taken on 10 July carried three embryos and had seven placental scars, whereas one of two taken on 11 and 12 July con- tained five embryos in addition to six placental scars. Two females trapped on 16 and 17 July carried seven and six embryos, respec- THE MAMMALS OF CARTER COUNTY, MONTANA 17 tively, the latter also containing five placental scars. One taken on 19 July had four corpora lutea and one obtained on 25 July was nonparous. An adult female examined on 29 July contained 11 pla- cental scars of at least two ages. One obtained on 1 August was lactating and had nine placental scars, and another trapped on 5 August carried five embryos and had six placental scars. Two adult males taken on 8 and 11 July had testes that were 11 and 6 mm in length, respectively. Average and extreme external and cranial measurements for 10 adults (two males, eight females) are: total length, 128.9 (125-136) mm; tail length, 59.7 (55-65) mm; hind foot length, 16.9 (16-18) mm; ear length, 6.6 (6-8) mm; basal length, 17.6 (17.2-18.3) mm; occipitonasal length (one male, six females), 11.9 (11.3-12.2) mm; interorbital breadth, 4.7 (4.5-5.0) mm; depth of cranium, 8.5 (8.3- 8.8) mm. Jones (1953:522) assigned an olive-backed pocket mouse from 8 mi NE Albion to P. f. olivaceogriseus. Andersen and Jones (1971: 376) and Genoways and Jones (1972:16) considered specimens from nortliwestem South Dakota and southwestern North Dakota, respectively, to be intergrades between the subspecies fasciatus and oUvaceofiriseus', but in both cases assign(^d specimens to fasciatus, mostly on the basis of color. Specimens from Carter County average slightly smaller and paler in color than do mice from those two ad- jacent areas. Therefore, we us(> the name olivaceogriseus to repre- sent olive-backed pocket mice from southeastern Montana, although they undoubtedly are intergrades between the two races. Our specimens of P. fasciatus were parasitized by a flea, Me- ringis sp., and three species of mites, Andwkielaps fahrenholzi, Ilaemogamasus sp., and Hirstionyssus sp. Perognathus hispidus paradoxus Merriam, 1889 Hispid Pocket Mouse Specimen examined ( 1 ). — 5 mi N, 3.5 mi W Camp Crook, 1. A nulliparous, subadult female, the first record of this species from Montana (Pefaur and Hoffmann, 1971:247), was trapped on a grassy slope at the eastern edge of the Long Pines. Mammals ti-apped in the same or adjacent trap lines included Sorex merriami, SpermophUus tridecemlineatus, Thomomys talpoides, Reithwdon- toniys megalotis, Peromyscus maniculatus, Microtus ochrogaster, Microtus pennsylvanicus, Mus musculus, and Zapus hudsonius. The hispid pocket mouse has also been recorded from adjacent Harding County, South Dakota (Andersen and Jones, 1971:377; Bime\' and Lampe, 1972:466), and northwestern Crook County, Wyoming (Long, 1965:618). 18 OCCASION.\L PAPERS MUSEUM OF NATURAL HISTORY Dipodomys ordii terrosus Hoffmeister, 1942 Ord's Kangaroo Rat The kangaroo rat evidently is uncommon in southeastern Mon- tana, being found in sandy areas along dry streams as well as on flats. We obtained no D. ordii, but its presence was reported to us, and Preble (MS) mentioned specimens from the Sioux National Forest near Ekalaka. Additionally, this rat is known from adjacent Harding County, South Dakota (Andersen and Jones, 1971:377), and Bowman County, North Dakota (Genoways and Jones, 1972: 18), and from but a few miles west of the Carter County boundary at Powdennlle, Powder River Countv, Montana (KU 14885-86 and 14912-13). Castor canadensis missouriensis Bailey, 1919 Beaver Beaver dams and freshly cut trees were noted along many of the streams and springs in the Long Pine Hills. An adult was observed at dusk on a large pond at Slick Creek Spring, 7 mi N and 10 mi W Camp Crook, 3800 ft, a place where numerous dams ( the largest 35 feet long and 10 feet high) had been built across steep ravines, the sides of which were clad with matm-e stands of ponderosa pine. The bark of some pines in an area up to 150 feet away from the ponds had been girdled to a height of about two feet. Pines nearest the ponds bore old scars and many were dead, whereas those on the periphery of the girdled area were freshly cut. No lodges were observed, although a cache of deciduous limbs and saplings was noted on a pond below Slick Creek Spring. Active dams also were found at other localities in the Long Pine Hills, as follows: Wick- ham Gulch, 2 mi N and 4.5 mi W Camp Crook, 3700 ft; Lantis Springs, 5.5 mi N and 10 mi W Camp Crook, 3500 ft; 4 mi N and 7.5 mi W Camp Crook, 3800 ft. Visher (1914:89) and others have reported beaver activity in Harding County, South Dakota — on Boxelder Creek and along the Little Missouri River. Beaver probably occur in these drainages in Carter County as well. Reithrodontomys megalotis dychei J. A. Allen, 1895 Western Harvest Mouse Specimens examined (2). — 5 mi N, 5.5 mi W Camp Crook, 3500 ft, 1; 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 1. This harvest mouse evidently is uncommon in southeastern Mon- tana. Our only two specimens, a subadult male and an adult male (testes 8 and 9 mm in length, respectively) were trapped in July from dense grassy areas in the eastern Long Pine Hills. THE MAMMALS OF CARTER COUNTY, MONTANA 19 Peromyscus maniculatus nebrascensis (Coues, 1877) Deer Mouse Specimens examined (152). — 11.5 mi N, 3 mi E Ekalaka, 23; 16 mi E Ekalaka, 3150 ft, 3; 17 mi E Ekalaka, 3200 ft, 15; 2 mi S, 1.5 mi E Ekalaka, 1 (MMNH); 3 mi S, .75 mi E Ekalaka, 7 (MMNH); 3 mi S, 1.75 mi E Eka- laka, 2 (MMNH); 3.75 mi S, 2.25 mi W Ekalaka, 4 (MMNH); 4.5 mi S, 1 mi E Ekalaka, 2 (MMNH); 11 mi S, 7.5 mi W Ekalaka, 2 (MMNH); 11 mi S, 7 mi W Ekalaka, 2; 11 mi S, 6.5 mi W Ekalaka, 3 (MMNH); 10.5 mi N, 5 mi W Camp Crook, 3400 ft, 1; 9 mi N, 11 mi W Camp Crook, 3600 ft, 1; 9 mi N, 3 mi W Camp Crook, 3400 ft, 2; 8.5 mi N, 8 mi W Camp Crook, 1; 7 mi N, 3 mi W Camp Crook, 3300 ft, 1; 5.5 mi N, 10 mi W Camp Crook, 3950 ft, 8 (6 MMNH); 5 mi N, 6 mi W Camp Crook, 3500 ft, 14; 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 31; 4 mi N, 8 mi W Camp Crook, 3650 ft, 7; 3.75 mi N, 7.75 mi W Camp Crook, 1 (MMNH); 2 mi N, 4.5 mi W Camp Crook, 3700 ft, 7; 8 mi S, 3 mi W Camp Crook, 3200 ft, 14. The deer mouse was by far the most common and widely dis- tributed mammal in Carter Count\'. We obtained specimens from all terrestrial habitats except dense stands of ponderosa pine having a sparse understor\'. Adults, subadults, and young (in juvenile pelage) were obtained in various stages of seasonal and maturation al molt throughout July and in early August. A pregnant femak^ was still in worn winter pelage on 25 July and an adult male and a pregnant female were molting to summer p{>lagc as late as 22 July. Adults of both sexes were taken in fresh summer pelage as early as 1 July, but most indi- viduals obtained early in July still were in winter pelage. In the first half of July, 12 females carried an average of 5.2 (3-7) embryos, the crown-rump length of which ranged from 3 to 14 mm. Eight individuals collected at this same time had an average of 6.1 (4-9) recent placental scars and two indi\'iduals were lactating. One captured during this period in 1972 had 11 placental scars of at least two age categories. In the second lialf of JuK', nine females carried an average of 5.0 (3-6) embryos that varied from 3 to 18 mm in length. An average of 4.5 placental scars was noted for four indi- viduals. Thirty-five adult males collected in the first half of July had testes with a mean length of 9.6 (8-11) mm, and 15 taken in the last half of July had testes whose average length was 9.9 (8-13) mm. Additionally, we obtained two females on 30 June that had four and five recent placental scars. Five males obtained on that date had testes that were 10.2 (10-11) mm in mean length. A subadult female taken on 1 August carried three 2 mm embryos. Peromyscus maniculatus were parasitized by the following ecto- parasites: a mite, Ancholaelaps fahrenholzi; ticks, Dermacentor andersoni and Ixodes sculptus; a louse, Hoplopleura hesperomydis; and fleas, CaUistopsyllus terimis, MonopsyJhis eumolpi eumolpi, Momypsyllus wagneri, and Monopsylhis sp. Three specimens were parasitized by cuterebrid larvae. 20 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY Onychomys leucogaster missouriensis (Aubudon and Bachman, 1851) Northern Grasshopper Mouse Specimen examined ( 1 ). — 11.5 mi N, 3 mi E Ekalaka, 1. A subadult male was trapped in a sandy draw bordered by short grass in Medicine Rocks State Park, an area of massive rock out- croppings in northern Carter County from which Preble (MS) also listed specimens. Although 240 traps were set on three consecutive nights in this area in mid-July, no additional Onychomys were ob- tained; however, Peromyscus maniculatiis, SpermophiJus tridecem- lineatus, and Perognathus fasciatus were obtained from the same or adjacent trap lines. The rarity of grasshopper mice in eastern Mon- tana was earlier mentioned by Preble ( MS ) . Our male, taken on 15 July, was molting actively as evinced by patches of new pelage on both shoulders and rump. The testes were 12 mm in length. Neotoma cinerea rupicola J. A. Allen, 1894 Bushv-tailed Woodrat Specimens examined (3). — 11 mi S, 6.5 mi W Ekalaka, 1 (MMNH); 7 mi N, 3 mi W Camp Crook, 3400 ft, 1; 3.75 mi N, 7.75 mi W Camp Crook, 1 (MMNH). Our three bushy-tailed woodrats were nulliparous females, ap- parently young of the year. One, trapped on 5 July under a rock ledge, was molting on the sides and rump. The other two, taken on 12 and 17 July, were completing molt into adult pelage. One was trapped under a large rock near the summit of Trenk Pass in the Chalk Buttes. The other was removed from an abandoned building. Nests and old fecal pellets of woodrats were found frequently in the Long Pine Hills; Merlin Tuttle examined contents of owl pellets (thought to be those of a great horned owl) from an abandoned farm in the Ekalaka Hills that contained remains of these woodrats. Andersen and Jones (1971:380) recorded a specimen from 7 mi N and 2.5 mi W Camp Crook, South Dakota, at the extreme eastern edge of the Long Pine Hills. Although none of our specimens was fully adult, we assign them to the subspecies rupicola rather than orolestes. They are indistin- guishable from a series assigned to rupicola by Andersen and Jones (1971), which includes several individuals of comparable age from Harding County, South Dakota. We are convinced that woodrats living in the several hills and buttes of this tri-state area are of a single taxon. THE MAMMALS OF CARTER COUNTY, MONTANA 21 Microtus ochrogaster haydenii (Baird, 1858) Prairie Vole Specimens examined (6). — 9 mi N, 3 mi W Camp Crook, 3300 ft, 3; 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 3. Tliree specimens were trapped in an ungrazed upland meadow, 5 mi N and 3.5 mi W Camp Crook, and the remaining three were collected from the semi-marshy banks of a small stream in a lightly grazed pasture of sweet clover. M. pennsyhaniciis and M. ochro- gaster were taken together at the former localit\'; howe\'er, 600 trap nights in the vicinit)' of the stream at the latter locality^ produced no specimens oi pennsylvaniciis. Jones ( 1964:228), Turner (1974:116), and others have noted that the prairie vole occupies riparian habi- tats in the absence of pennsylvonicus but is excluded from such habitats when both species are present. One praire vole harbored a flea, Orchopeas leucopus, and a chig- ger, Euschoengastia setosa. Microtus pennsylvanicus insperatus (J. A. Allen, 1894) Meadow Vole Specimens examined (71). — 1.73 mi S, 1 mi E Ekakika, 1 (MMNH); 2 mi S, 1.5 mi E Ekakka, 2 (MMNH); 3 mi S, 1.75 mi E Ekalaka, 27 (MMNH); 8.5 mi N, 8 mi W Camp Crook, 3400 ft, 1; 5.5 mi N, 10 mi W Camp Crook, 10 (MMNH); 5 mi N, 10 mi W Camp Crook, 2; 5 mi N, 6 mi W Camp Crook, 3500 ft, 1; 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 5; 3.75 mi N, 7.75 mi W Camp Crook, 18 (MMNH); 2 mi N, 4.5 mi W Camp Crook, 3700 ft, 1; 8 mi S, 3 mi W Camp Crook, 3200 ft, 3. The meadow vole was the most abimdant microtinc in Carter County. It was found in grasslands and lush riparian habitats in the Long Pine Hills as well as along the Little Missouri River. Although we have no specimens from within the Ekalaka Hills, many of these voles were trapped along streams that flow northward from there. The number of specimens collected was small in comparison to the density of runways observed in many areas that were trapped. Preble (MS) earlier mentioned specimens from Medicine Rocks, Ekalaka, Capitol, and Albion. Of 26 females obtained in Juh', 10 carried an average of 6.7 embr>'OS (5-9) that ranged in length from 4 to 29 mm. Four females were recorded as lactating in early and mid-July; three other indi- viduals had recent placental scars. Testes of 34 adult and subadult males taken in mid-Juh^ ^^'ere 14.6 (9-20) mm in average length and those of an adult taken in early August were 18 mm. Molt was observed in adult, subadult, and juvenile individuals collected in July and early August. Our specimens of meadow \oles were parasitized by a mite, Laelaps kochi, and a louse, Hoplopleura acanthopus. 22 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY Lagurus curtatus pallidas (Merriam, 1888) Sagebrush Vole Specimen examined ( 1 ). — 16 mi E Ekalaka, 3150 ft, 1. An adult male, trapped on 8 July on a sagebrush flat in the north- eastern part of the count)', was the only sagebrush vole olotained. Fecal pellets and runways occasionally were found under large clumps of sagebrush in this area, but extensive trapping, employing both break-back and can traps, produced no additional individuals. Peromyscus maniculatus and Spermophihis triclecemJineatiis were obtained in this habitat. Bailey (1927:101) earlier commented on the difficulty of collecting sagebrush \'oles in North Dakota. The species evidently is relatively rare and of localized occurrence along the eastern edge of its range. Preble ( MS ) mentioned specimens from Medicine Rocks, 15 mi N Ekalaka [probably 11.5 mi N and 3 mi E Ekalaka], and from 5 mi SE Ekalaka. Birney and Lampe (1972:466) reported the only specimens of sagebrush voles known from South Dakota. The spe- cies also is known adjacent to Carter County in southwestern Pow- der River Count}^ (Hoffmann et al., 1969a: 592) and southwestern Bowman County, North Dakota (Genoways and Jones, 1972:24). Our specimen was molting as evinced by small irregular patches of new pelage on head, back, and sides, and had testes that were 11 mm in length. External and cranial measurements are: total length, 139 mm; tail length, 19 mm; hind foot length, 16 mm; ear length, 12 mm; weight, 38.2 gms; condylobasal length, 25.9 mm; palatal length, 14.8 mm; interorbital breadth, 3.1 mm; zygomatic breadth, 15.5 mm; maxillary toothrow length, 7.0 mm. Mus musculus Linnaeus, 1758 House Mouse Specimens examined (3). — 3 mi S, 1.75 mi E Ekalaka, 1 (MMNH); 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 2. Two adult house mice, a male and a female, were collected on a north-facing slope of a grassy meadow at the eastern edge of the Long Pine Hills. Both were taken on a grid that previously had been live-trapped for 10 days in a trap-release program, then snap- trapped. No house mice were obtained in live-traps on this grid nor were any taken in either live-traps or snap-traps on two adjacent grids. Our third specimen, an adult male, was trapped in a marsh along with Zapus hudsoniiis, Microtus pennsylvaniciis, and Pero- myscus maniculatus. Preble ( MS ) commented that house mice generally were dis- tributed in eastern Montana in the proximity of railroads. Andersen and Jones (1971:381) recorded a single individual, trapped along a fencerow, from adjacent Harding County, South Dakota. THE MAMMALS OF CARTER COUNTY, MONTANA 23 Zapus hudsonius campestris Preble, 1899 Meadow Jumping Mouse Specimens examined (33). — 3 mi S, 1.75 mi E Ekalaka, 21 (MMNH); 5.5 mi N, 10 mi W Camp Crook, 3 (MMNH); 5 mi N, 5.5 mi W Camp Crook, 3500 ft, 2; 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 2; 4 mi N, 8 mi W Camp Crook, 3650 ft, 2; 3.75 mi N, 7.75 mi W Camp Crook, 1 (MMNH); 2 mi N, 4.5 mi W Camp Crook, 3700 ft, 1; 8 mi S, 3 mi W Camp Crook, 3200 ft, 1. Twenty-one of our specimens were trapped from a large marsh at the north edge of the Ekalaka Hills. The remainder were ob- tained from riparian and marshy habitats in the Long Pine Hills, along the Little Missouri River, and on a grassy upland slope at the eastern edge of the Long Pines. Of our 33 specimens, all caught in July, 25 were adult, and only eight were juvenile or subadult (see Krutzsch, 1954:377, for criteria of age classes). Testes of 13 adult males were 6.1 mm in mean length whereas those of six young males were 4.7 mm. Of the 14 females in our sample, six were carrying embryos that ranged in length from 6 to 19 mm. Mean and modal number of cmbr\'os per pregnant female was 6.0 and 7, respectively. Three adult and five young females were neither pregnant nor lac- tating. Preble (MS) recorded specimens from Ekalaka and the Sioux National Forest. Intcrgradation between the subspecies campestris and inter- medius has been suggested in Harding County, South Dakota (An- dersen and Jones, 1971:3(82), and in Dawson Count) of east-central Montana (Krutzscli, 1954:448). Average and extreme cranial meas- urements of 19 adults (11 males, 8 females) are: condylobasal length, 21.2 (20.1-22.2) mm; occipitonasal length, 23.3 (22.3-24.0) mm; palatal length, 10.1 (9.7-10.5) mm; mastoidal breadth, 10.3 (10.0-10.7) mm; maxillary toothrow length, 3.7 (3.5-4.1) mm. In their more ochraceous color, our specimens more closeh' resemble campestris from Harding Count>-, South Dakota and the Black Hills, than intermedins from North Dakota. Erethizon dorsatum bruneri Swenk, 1916 Porcupine Specimen examined ( 1 ). — 7 mi N, 3 mi W Camp Crook, 3400 ft, 1. An adult male weighing 27 pounds was shot in the late afternoon of 4 July in a den located under a rock ledge on a pine-clad ridge along the eastern edge of the Lone Pine Hills. In addition, we ob- served an individual in a meadow, 5 mi N and 3.5 mi W Camp Crook, and two others on a road near Lantis Spring, 5.5 mi N and 10 mi W Camp Crook. Fresh sign of porcupines was seen elsewhere in the Long Pines. The species exidently is fairh' common there and, presumably, in adjacent pine-covered areas. 24 OCCASION.\L PAPERS MUSEUM OF NATURAL HISTORY Order Carnivora Canis latrans latrans Say, 1823 Coyote The coyote population of Carter County was apparently ex- tremely low at the time of our studies, perhaps as a result of active predator conti'ol practices, including 1080 poison. This compound is currently banned, and coyotes are reported increasing in many places. Our field parties neither saw nor heard coyotes. Visher (1914:90) reported that during the winter of 1910-11 one trapper collected 102 coyotes in the Ekalaka Forest. During the period July 1970 to June 1971, bounties were paid on four coyotes purportedly taken in Carter County. Andersen and Jones (1971:382) listed two specimens obtained by a federal trapper during the winter of 1961- 62 along the eastern edge of the Long Pine Hills, 6 mi N and 4 mi W Camp Crook, Harding County, South Dakota. Canis lupus nubilus Say, 1823 Wolf The wolf, although now extirpated (Goldman, 1944:442), once ranged throughout Carter County. Bailey (1907:10) reported that in 1893 "wolves were common at Alzada and Powderville, and were veiy destructive to stock, especially calves and colts." Visher (1914: 90) noted that during the winter of 1909-10 a trapper took four wolves in the Ekalaka Forest, and Goldman (1944:444) listed a specimen from Ekalaka. Extirpation of the wolf in Carter County most likely paralleled in time its disappearance from Harding County, South Dakota (see Andersen and Jones, 1971:383). Populations may have remained slightly longer than elsewhere in the Long Pine Hills and forested areas near Ekalaka, although such areas were exploited heavily by commercial trappers. Vulpes vulpes regalis Merriam, 1900 Red Fox We took no specimens of this fox in Carter County, but an imma- ture female, captured approximately 5 mi W Camp Crook, was held as a pet by a local family. An adult was sighted on the night of 26 July 1970 on a sagebrush flat just north of the Long Pines and an- other was seen on the night of 17 July 1971 on a U.S. Forest Service road in the Ekalaka Hills. Visher (1914:90) reported the red fox as "not rare about the Long Pines" in the early part of the century. During the period 1 July 1970 to 16 July 1971, Carter County paid bounties on 958 red foxes. The extent to which predator con- trol programs have affected red fox populations is unknown, but Andersen and Jones (1971:383) reported that in adjacent Harding THE MAMMALS OF CARTER COUNTY, MONTANA 25 County, South Dakota, this fox "seems to maintain considerably higher populations than does the coyote," in spite of control pressure. Ursus arctos horriblilis Ord, 1815 Grizzly Bear The skull of a grizzly bear displayed in the Carter County Mu- seum in Ekalaka, was found in 1920 on Cottonwood Creek, T 5 S and R 61 E, in southern Carter Count}'. The specimen e\^idently had been shot inasmuch as there appears to be a bullet hole above the orbits. Visher (1914:91) noted that during the early 1890's a grizzly bear was killed a short distance southwest of Camp Crook. Additionally, a cave wall in the Cottonwood Creek area carries the inscription "Killed Bear in nest" (M. E. Lambert, pers. com.), which may refer to this or the following species. Ursus americanus americanus Pallas, 1780 Black Bear Visher (1914:91) reported that "Bears have been recently killed in the Long Pine and Ekalaka forests, but their day of extermination is here near at hand." Preble ( MS ) indicated that black bears for- merly were widely distributed in eastern Montana. Procyon lotor hirtus Nelson and Goldman, 1930 Raccoon Our only records of the raccoon in Carter County are of tracks found in the Long Pines along the edge of a beaver pond, 4 mi N and 8 mi W Camp Crook, and a specimen from 3 mi W Alzada (Hoffmann et ah, 1969a: 595). An adult was observed on several nights in July, however, on a ridge at the extreme eastern edge of the Long Pine Hills just inside Harding County, South Dakota, and Andersen and Jones ( 1971:384) reported a litter of five young found in May in this same area. They noted that this species "evidently is one of the commonest carnivores" in northwestern South Dakota and raccoons likely occur along the Little Missouri River and in other suitable riparian habitats in Carter Count)-. Mustela frenata longicauda Bonaparte, 1838 Long-tailed Weasel Specimens examined (2). — 3 mi S, 1.75 mi E Ekalaka, 1 (MMNH); 7 mi N, 4 mi W Camp Crook, 1. The mummified body of a long-tailed weasel in winter pelage was found on a sparsely forested ridge at the eastern edge of the Long Pine Hills. From size and cranial characters, we judge tliis specimen to be a female. A second weasel, a \'oung male, was cap- tured in a hand-held rat trap by Larry Heaney at the entrance to a 26 OCCASION.\L PAPERS MUSEUM OF NATURAL HISTORY pocket gopher burrow on 17 July. A partially eaten gopher had been removed from the burrow minutes before following a minor tug-of-war with the weasel. The rat trap was then baited with meat of the dead gopher. Preble (MS) noted that this species ". . . ap- pears generally distributed but nowhere abundant" in southeastern Montana. Mandibular formation is anomalous in the mummy; the length of the right mandible is 25.8 mm whereas the length of the left man- dible is 28.1. Extension of the left mandible caused a slight labial curve in the distal portion of the right mandible, nonalignment of the left upper and lower canines, and malocclusion of upper and lower incisors. The lower left canine does not occlude with the upper, but is directed more anteriorly and occludes with the left i2 and i3, which in turn have been pushed posteriorly toward the upper left canine. Both second lower incisors are situated posterior to il and i3. Mustela nigripes (Aububon and Bachman, 1851) Black-footed Ferret Specimen examined (1). — Piniele, 1. Cahalane (1954:419) reported that an adult male black-footed ferret was killed on 3 November 1953 on a highway north of Alzada, in southern Carter County. Additionally, Henderson et al. (1969) listed seven localities of record in Harding County, South Dakota, two of which are in townships adjoining Carter County (T 19 N, R 1 E, and T 15 N, R 1 E), and we have examined museum specimens from Custer County, Montana, adjacent to Carter County to the northwest. A skin and partial skeleton ( KU 14411 ) of an adult mentioned by Hoffmann et al. (1969a: 597) was obtained in October 1944 at Piniele in southwestern Carter County. In view of its small size, this speci- men most likely represents a female. Selected cranial measurements are: condylobasal length, 66.8 mm; palatal length, 30.8 mm; mastoid breadth, 33.8 mm; least interorbital breadth, 16.7 mm; postorbital breadth, 10.7 mm; maxillary toothrow length, 19.1 mm. Close dependence of the black-footed ferret on prairie dogs as a major food source no doubt has had a serious impact on the current status of this mustelid, although it may never have been abundant. Efforts to reduce or extirpate prairie dogs continue in Carter County and elsewhere in southeastern Montana. Taxidea taxus taxus (Schreber, 1778) Badger Specimen examined ( 1 ). — 8 mi S, 3 mi W Camp Crook, 3700 ft, 1. Badgers probably occur throughout Carter County. A subadult male with testes that were 49 mm in length was trapped on 8 July THE MAMMALS OF CARTER COUNTY, MONTANA 27 at a den located in the north face of a gulley along the Little Mis- souri River. The stomach of this specimen contained the remains of three Thomomys taJpoides, a small bird, five bees, and unidentified plant material. A subadult observed crossing a road in the sage- brush flats to the north of the Long Pine Hills, 1 mi S and 13 mi E Ekalaka, 3200 ft, in the late afternoon of 14 July escaped to a nearby burrow after it dropped an immature prairie dog that it carried in its mouth. Our one specimen harbored a tick, Ixodes kingi. Mephitis mephitis hudsonica Richardson, 1829 Striped Skunk Specimens examined (4). — 8.5 mi N, 8.5 mi W Camp Crook, 3400 ft, 2; 6 mi N, 9 mi W Camp Crook, 2. Striped skunks evidently are common in the Long Pine Hills and surrounding areas. Two of our four specimens were collected from a densely wooded slope in the Long Pines — one trapped along a game trail and the other picked up in the field as a skeleton. The other two specimens, a young male ( testes 2 mm in length ) and an adult female ( six placental scars ) , were shot on the night of 16 July along a road in rolling grasslands just to the north of the eastern part of the Long Pines. Striped skunks were obsen^ed frequently in the Long Pine Hills. Our only sight record other than from that area was of a young animal killed on a road in the vicinit}' of Sheep Mountain, 4 mi S and 11 mi W Camp Crook. Andersen and Jones (1971:385) re- ported an observation from just east of the Long Pines at a place 6 mi N and 2.5 mi W Camp Crook, Harding County, South Dakota. The young male shot on 16 July was parasitized by a tick, Ixodes kitiQi. •&* Felis concolor hippolestes Merriam, 1897 Mountain Lion Mountain lions, "formerh of quite general distribution over the eastern part of Montana" (Preble, MS), have been extirpated in the southeastern part of the state. Visher (1914:91) noted that the mountain lion that visited Harding Count}-, South Dakota, during the winter of 1910-11 "was doubtless a roamer from the Long Pines or Ekalaka Forests." The presence of this cat in Carter County prob- ably now is limited to an occasional transient. Order Artiodactyla Cervus elaphus canadensis Erxleben, 1777 Wapiti or Elk Prior to the appearance of homesteaders and hunters, elk were 28 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY common on the plains of eastern Montana. In a summary of his- torical accounts of big game in Montana, Koch (1941:368) noted "that they [elk and bison] occurred in vastly greater numbers in the plains country, with some timber or mountain shelter, than they did in the higher mountain country. ..." Preble (MS) mentioned that elk formerly were distributed over southeastern Montana and Visher (1914:87) reported that the "last [elk] were killed in 1879 when a large crew cut trees for the N.P.R.R. in the Long Pines." A fragment of an elk antler was found (M. E. Lambert, pers. com.) in "a timbered area of the Chalk Buttes about twenty miles south of Ekalaka." Odocoileus hemionus hemionus (Rafinesque, 1817) Mule Deer Mule deer commonly were seen in meadows and occasionally along ridges in the Lone Pine Hills and Chalk Buttes. Preble (MS) reported this deer to be generally distributed throughout eastern Montana in the early part of this centuiy. Mule deer may be more numerous in Carter County than are white-tailed deer; in the Long Pines, however, we found the latter to be the more numerous. Sight records other than from the Long Pine Hills are from 1.5 mi N and 5.5 mi E Ekalaka (six bucks) and 4 mi SE Ekalaka (four does and one fawn ) . Odocoileus virginianus dacotensis Goldman and Kellogg, 1940 White-tailed Deer Specimens examined (6). — 8.5 mi N, 13 mi W Camp Crook, 2 (MMNH); 5.5 mi N, 10 mi W Camp Crook, 3400 ft, 1; 5 mi N, 3.5 mi W Camp Crook, 3400 ft, 1; 4 mi N, 9 mi W Camp Crook, 3950 ft, 2. We frequently observed white-tailed deer in the Long Pine Hills, mainly along the pine-covered ridges and in meadows adjacent to such ridges. Our only observation of white-tails outside the Long Pines was of a doe, accompanied by a fawn, resting among decid- uous brush along the Little Missouri River at a place 8 mi S and 3 mi W Camp Crook. Preble (MS) reported white-tailed deer "... to be more commonly met with in the southeastern part of the State than elsewhere [in eastern Montana]." No group of more than five deer was obseived. Several does with fawns repeatedly were seen grazing in grassy draws in early and mid-July. All of our specimens are skulls picked up in the Long Pines. Antilocapra americana americana (Ord, 1815) Pronghorn Pronghorns regularly were seen in the grasslands, and occasion- ally in meadows, along the margin of the Long Pines in the summer THE MAMMALS OF CARTER COUNTY, MONTANA 29 of 1970. Beer (1944:45) reported that in 1941 Carter County had the largest number of pronghorns, an estimated 2500, of any county in Montana. He also noted that in severe winters pronghorns mi- grated into the area from Soutli Dakota, seeking shelter among the breaks and ridges along the Little Missouri River. Andersen and Jones (1971:387) reported sighting herds of up to 50 individuals in adjacent Harding County, South Dakota; all of our observations, however, were of groups of five or less. While conducting an aerial census of pronghorns in Carter County on 28 January 1948, Thompson (1949:313) observed an adult golden eagle attacking a single adult male pronghorn near the rear of a herd of 64 individuals. In three consecutive attacks, the eagle grasped the back of the animal and rode with outspread wings as the pronghorn fled with the herd across open grassland. We have no such observations of predation, but golden eagles were sighted in the Long Pines as well as over adjacent grasslands. An analysis of pronghorn stomach contents, conducted in Carter County from September through December of 1944 and 1945 (Couey, 1946:367), revealed tliat sagebrush (Artemisia triclentata and A. cana), snowberry (Symphorirarpos sp.), and snakeweed (Gtiterriezia sp. ) composed 75 per ccMit of the diet by volume. Bison bison bison (Linnaeus, 1758) Bison Vast herds of l)ison are known to have occurred along the Mis- souri and Yellowstone ri\'ers as well as across the prairies of what is now Carter County until the middle of the 19th century. During the exploration of the Yellowstone River and its tributaries in 1859, Captain W. F. Raynolds and his party crossed the extreme south- western corner of Carter County, \\niile camped near the present border betwecMi Carter County, Montana, and Crook County, \\^y- oming, on 21 June, he noted ( 1868:33) : "^^\' are now in the buffalo region, and small herds are to be seen in all directions. Their pres- ence may explain some of the prevalent barrenness, as they consume all the grass in their paths." During an expedition to the Black Hills in July 1874, Custer traveled down the Little Missouri River and entered southeastern Carter County, then part of the Montana Ter- ritory. Custer found (1875:1) "this valley [of the Little Missouri River] almost destitute of grazing ..." a condition perhaps attribu- table to bison. J. A. Allen (1877:545) noted that by 1877, between the Platte and Missouri rivers, bison were confined to the area of the Bighorn, Tongue, and Powder rivers. Indian hostilities, which prevented ex- ploitation of the eastern Montana herds, were curtailed in the mid- 1870's, opening the territory to "civilization" and the extirpation of the remaining bison. Visher (1914:88) reported "a small bunch" in 30 OCCASIOx\AL PAPERS MUSEUM OF NATURAL HISTORY Harding County, South Dakota, in 1886 and commented on the occurrence of numerous bullet-riddled skulls testifving to the activ- ities of "market shooters." Ovis canadensis auduboni Merriam, 1901 Bighorn Sheep Bighorn sheep once were abundant in eastern Montana (Preble, MS ) and specimens were collected in the late 1800's in the badlands and high plateaus along the Little Missouri River in North Dakota (Buechner, 1960:20). The mounted head of a bighorn displayed in the Carter County Museum, Ekalaka, Montana, was obtained by Dan Bowman in 1893 from the Powder River near Locate, Custer County, Montana. The only record of bighorn in Carter County consists of two pairs of honi cores, one "dug out of a spring twenty miles west of Ekalaka on Spring Creek," and the other "found on Tie Creek south of the Long Pines" (M. E. Lambert, pers. com.). The specimens are tenta- tively assigned to O. c. audiihoni, a subspecies now considered ex- tinct (Cowan, 1940:542). OTHER SPECIES Three additional species, the muskrat (Ondatra zibethicus), the mink (Mustela vison), and the bobcat (Lynx nifiis) most assuredly are found in Carter County as indicated by the availability of suit- able habitats and the presence of recent records (Andersen and Jones, 1971) from nearby areas. Although we obtained neither speci- mens nor sight records of these species, all three were reported by local residents. Additionally, during the fiscal year 1970-71, bounties were paid in Carter County for 130 bobcat and lynx. Individuals were not identified to species, but we believe that most, if not all, were Lynx rufus. Species of Unverified Occurrence Twelve species listed below may occur (or in the recent past probably occurred) in Carter County. The possible presence of 10 species is inferred by their distribution and habitat preference in areas adjacent to Carter County. A published account of migration of the Norway rat (Tryon, 1947) and the mention of lynx in an unpublished manuscript by Preble also are noted. Preble's mention of Lepiis americanus from the forested areas near Ekalaka almost certainly was in error as this hare now occurs no nearer Carter County than in the Killdeer Mountains of North Dakota ( Genoways and Jones, 1972:9), Richland County, Montana (Hoffmann et ah, 1969a:584), and the Bighorn Mountains of Wyoming (Long, 1967: 548). SyJviJagus nuttaUii gran^ien (J. A. Allen, 1895). — Although this cottontail is not presently known from Carter County, it may be THE MAMMALS OF CARTER COUNTY, MONTANA 31 found along the wooded and brush}' streams in the hills along the western and southern edge of the county. Specimens have been taken a short distance to the south in Crook County, Wyoming (Long, 1965:544). Marmota flaviventris dacota (Merriam). — The yellow-bellied marmot is known to occur in the Black Hills (Turner, 1974:68) and adjacent regions in Wyoming (Long, 1965:570). Hoffmann et ah (1969a: 568) reported marmots from Rosebud County, Montana, which is west of Carter Count>'. The presence of yellow-bellied marmots among rocky outcrops in Carter County is possible, al- though we observed no sign of the species. Reithrodontomys montanus albescens Cary, 1903. — The plains harvest mouse has been reported (Andersen and Jones, 1971:378) from adjacent Harding Count}', South Dakota, where it was rare in upland grassy habitats. In northeastern Wyoming, it is known from northern Campbell Count}' (Long, 1965:626). The species has not been reported from Montana. Peromyscus leucopiis aridulus Osgood, 1909. — The white-footed mouse may be present in the county in small discontinuous popula- tions, similar to the isolated population reported by Andersen and Jones (1971:378) in adjacent Harding County. South Dakota. The species is known from Crook County, Wyoming (Long, 1965:634), and elsewhere in Montana (Hoffmann et ah, 1969a: 590). However, we trapped unsuccessfully for this species in a variety of habitats. Rattiis norvegicus (Berkenhout, 1769). — Tryon (1947:188) in- cluded northeastern Carter County within the range of migration of rats that had reached eastern Montana in the late 1940's from North Dakota. Migrational routes in eastern Montana followed highways and railroads, and therefore, were primarih' in \'alle}s. We know of no specimens of the Norway rat from Carter County. Vulpes velox (Say, 1823). — The swift fox no doubt occurred in Carter County within historic times, but there are no actual records of its presence. Hoffmann et ah (1969a: 594) regarded the species as "now probably extinct in the state." However, it is noteworthy that a specimen was taken in nearbx' Slope County, North Dakota, on 20 Februar}' 1970 (Pfeifer and Hibbard, 1970:835). Urocyon cinereoargenteus ocythous Bangs, 1899. — Although no records of the gray fox are known from Montana, an adult male has been recorded (Jones and Henderson, 1963:283) from 43 miles east of Carter County at Deer Ear Buttes, Butte Co., South Dakota. This record constituted a considerable westward extension of the then known range and possibly is indicative of a trend in dispersal of this species. Mustela erminea muricus (Bangs, 1899). — No specimens of this weasel have been reported from eastern Montana. However, the 32 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY proximity of a recent record (Long, 1965:692) from Crook County, Wyoming, at a place 40 miles south of Carter County, suggests the possible occurrence of the ermine in the southeastern part of the state. Gtilo gulo hiscus (Linnaeus, 1758). — The wolverine, although probably never abundant, likely occurred in southeastern Montana within historic time. Spilogale putorius interrupta (Rafinesque, 1(320). — Southeastern Montana was included in the distribution of the spotted skunk by Hoffmann and Pattie (1968:117), although no specimens have been reported from the area. Visher (1914:91) commented that the spotted skunk was more abundant than the "large skunk" in north- western South Dakota, but Andersen and Jones (1971:385) more recently reported the species as rare there. Lontrci canadensis pacifica (Schreber, 1776). — Preble (MS) com- mented that the otter once occurred in small numbers in eastern Montana, and Visher (1914:91) reported a specimen taken on the Little Missouri River in Harding County, South Dakota. We follow van Zyll de Jong ( 1972 ) in the use of generic and subspecies names of the otter. Lynx canadensis canadensis Kerr, 1792. — Lynx populations in Montana have recently shown a marked increase, but this cat is un- common in the southeastern part of the state (Hoffmann et ah, 1969a: 598). No records of the species are known from Carter County, where it no doubt once occurred and may again be found. Although it has been suggested that L. canadensis is conspecific with L. lynx of the Old World, we follow Kurten and Rausch (1959: 41) in regarding them as specifically distinct. ZOOGEOGRAPHIC COMMENTS Faunal Components The 50 native North American species known as recent inliabi- tants of southeastern Montana exhibit five distributional patterns, the implications of which have been discussed by Hoffmann and Jones ( 1970). The largest faunal grouping consists of species having widespread distributions. These species either occupy much of tem- perate North America, or have distributions that do not coincide with any major faunal unit. The 23 species so categorized are: Myotis leibii, Myotis lucifiigus, Lasionyctcris noctivagans, Eptesicus fusctis, Lasiunis cinereus. Castor canadensis, Feroniyscus manicu- latus, Erethizon dorsatum, Canis latrans, Canis lupus, Vulpes vulpes, Ursus arctos, Ursus americanus, Procyon lotor, Mustela frenata, Taxi- dea taxus. Mephitis mephitis, Felis concolor, Cervus ehiphus, Odo- coileus hemionus, Odocoileus virginianus, Antdocapra americana, and Bison bison. Many of these mammals are vagilc and eur) topic species, or species with specializations that are met in more than a THE MAMMALS OF CARTER COUNTY, MONTANA 33 single biotope (for example, the beaver). The wolf, grizzly bear, black bear, mountain lion, elk, bison, and bighorn sheep have been extirpated in southeastern Montana directly or indirectly by man. The reduction of coyote populations elsewhere in Montana (Hoff- mann et ah, 1969a: 596) and in \^^'oming (Robinson, 1961, and Lin- hart and Robinson, 1972) had been followed by increased popu- lations of other carnivores, such as skunk, badger, lynx, and red fox; the last-mentioned species recently has extended its range westward in Montana (Hoffmann et ah, 1969a: 594). Although these wide-ranging carnivores occurred in grasslands, the mountain lion and black bear were more likely to be found among rocky buttes and ridges and the raccoon is more t\'pical of the floodplain forests. The porcupine, although associated princi- pally with coniferous forests, herein is considered a "widespread species" because of its extensive distribution. The mule deer and pronghorn are essentially western species, whereas the white-tailed deer is a wide-ranging species. Although a common plains mammal, the bison had an extensive northern and eastern distribution. Three of the five bats are apparently permanent residents of the area, Lasiurus and Lasionyctcris being migrants. Boreomontane species. — Three bats, Myotis evotis, Myotis vo- lans, Plecotus townsendii, as well as Thomomys talpnicles, Neotoma cinerea, and Ovis canadensis are primarily montane species, al- though the first, second, third, and sixth species also ha\'e extensive southwestern distriliutions. Four species (Sorer cinercus, Etitamitis minimus, Tamiasciiinis hudsonicus, and Micwtus pennsylvaniciis) occur in boreal areas to the north as well as montane areas to the west. Zaptis hiidsonitis, basically a boreal species, also inhabits much of the eastern deciduous forest. All of these species, except the three bats, have developed distinctive subspecies on the Northern Great Plains. Steppe species. — Steppe species have evolved in close association with the grassland environment; they are characteristic of, and more or less restricted to, such areas. Steppe species occurring in south- eastern Montana are Lepiis townsendii, Cynomys ludovicianus, SpermophUus tridecemlineatus, Ferognathus fasciatus, Perognathus hispidus, Microtus ocJiwgaster, and Mustela ni gripes. Indicative of such autochthonous influence is the close predator-prey relationship of the prairie dog and the black-footed ferret. Sonoran species. — Species that have invaded the area from the Southwest are Sylvdagus auduhonii, Dipodomys ordii, Reithrodon- tomys megalotis, and OnycJioniys leucogaster. The last two species now inhabit much of the Northern Great Plains as well as areas of the Great Basin. Great Basin species. — Two species have in\'aded the plains from the Great Basin. The sagebrush vole (Lagurus curtatus) most likely 34 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY entered the Northern Great Plains through the Wyoming Basin (Hoffmann and Jones, 1970:370). Knowledge of the distribution of Sorex merriami, although this shrew is widespread in the Great Basin, is limited by a lack of specimens. Eastern species. — The eastern cottontail (SylviJagus ftoridanus) reaches its northwesternmost known distribution in Carter County, where it is closely associated with riparian habitats. Found pri- marily east of the Rocky Mountains, one subspecies of this rabbit, S. /. similis, has developed on portions of the Northern and Central Great Plains. Another eastern species, Sciurus niii,er, is a recent in- vader, and most likely entered the area from the northeast along the Little Missouri River, where it is restricted to the deciduous flood- plain forest. Unverified species. — Eleven of the 12 species of unverified oc- currence in Carter County are native North American mammals. Of these 11, five (Sijlvilagus nuttallii, Marmota faviventris, Mtistela erminea, Giilo gtdo, and Lynx canadensis have boreal or montane affinities, two (Peromyscus leucopus and Urocyon cinereoargentetis) are associated with the casern forest, three ( Reithrodontomys mon- taniis, Vidpes velox, and SpiJogale piitorius) are steppe species, and one (Lontra canadensis) is a widespread species. Fatinal Comparisons In order to add greater perspective to the zoogeographic rela- tionships of the mammalian fauna of southeastern Montana, we have compared it with the faunas from two other sites on the Northern Great Plains. Southern Saskatchewan, a Transition and Upper So- noran zone of parkland and prairie bordered on the east, south, and west by the Saskatchewan and Qu'Appelle rivers, is representative of the northern extent of the Great Plains. Northwestern Nebraska (Sioux, Dawes, and Sheridan counties) comprises a southern site that includes the Pine Ridge district of the High Plains and the Pierre Plains of the Missouri Plateau. Carter County, Montana, and ad- jacent Harding County, South Dakota, form a unit representing a central location on the Northern Great Plains. The mammals of southern Saskatchewan have recently been examined by Beck (1958) and Soper (1961). The distributional records of Jones (1964) and McDaniel (1967) were used to compile a list of mammals of northwestern Nebraska. The foregoing ac- counts and those by Andersen and Jones ( 1971 ) for adjacent Hard- ing Count}' were combined for the mammalian fauna of the central site. The past and present distribution of many carnivores and artiodactyls is uncertain and members of these two orders thus are excluded from the following discussion. Of a total of 51 species of small mammals found at the three sites, 24 species are common to all. Although the number of THE MAMMALS OF CARTER COUNTY, MONTANA 35 Table 2. Composition of small mammal faunas of three regions on the Northern Great Plains; see text for discussion and sources of figures. Northwestern Northwestern South Dakota Southern Taxa Nebraska Southeastern Montana Saskatchewan Insectiv'ora 3 2 4 Chiroptera 7 8 6 Lagomorpha 4 3 4 Rodentia 23 22 23 Species present at each site is similar (Table 2), the species compo- sition varies considerably. Of the 11 species restricted to southern Saskatchewan, six (Sorex va^rans, Microsorex hoiji, Sylvila^us nttt- talii, Lepus americamis, GJaucomijs sahrinus, and Clethnonomijs gapperi) are of boreal or montane distribution and three {Blarina brevicaiicia, Lasiurus borealis, and Marmota monax) have aflBnities with the eastern deciduous forest. Two sciurid rodents, Spermophi- lus richardsonii and Spermophilus frauklinii, are restricted to the northern site and are, respectively, of Great Basin and (eastern) steppe affinities. A montane bat species, Plecotus townsendii, is, among the three faunas, the only species found only in the south- eastern Montana-northwestern South Dakota area. The five species foimd onh' in northwestern Nebraska consist of two steppe species {Geomi/s J)tirsaritis and Perognafhiis favescens) , two Sonoran spe- cies (Lepus caJiforniciis and Sperninphihis spilosoma), and one eastern species (ScaJo)nis aqiiaticiis). It is apparent, although not suiprising, that the northern and southern sites support faunistic elements of somewhat different distributional affinities. It is inter- esting to note that but a single species is found solely at the central site. The two species common onlx^ to the northern and central sam- ples are the boreal Tomiasciurus Jiudsonicus and the invader from the Great Basin, Lagurus ciirtatus. Two steppe species (Pero- gnathtis hispidiis and Reithrodontomys montamis), two Sonoran species (Sylvilagus audubonii and Reithrondontomys megalotis), two montane species (Myotis evotis and Myotis volans), one eastern deciduous woodland species (Schirus niger), and one Great Basin species (Sorex merriami) are common to the central and southern sites. There are no species shared b\' the northern and southern sites to the exclusion of the Montana-South Dakota region. As its geographic location suggests, the Montana-South Dakota sample represents an "intermediate" fauna inasmuch as all but one species is shared with either the northern or southern samples. The presence of eight species shared by the central and southern sam- ples in comparison to two species common to the northern and cen- tral units is notewortliy. The boreomontane element, prevalent in 36 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY southern Saskatchewan, is limited at the central site and to an even greater degree at the southern site, probably owing to such features as temperature, amount of precipitation, and nature and extent of forest habitats. Grassland invaders have been aided in their post- Wisconsin dispersal by the continuity of the grassland environment. Several of the steppe and grassland-associated species present at the southern site have reached the Montana-South Dakota area, but are absent in Saskatchewan. , SUMMARY Fifty-three species of mammals are reported to have occurred in Carter County, Montana, within historical times. In addition, 12 species are noted as having a possible but imverified occurrence in the county. Annotated accounts of these 65 species provide com- ments on their distributional status and natural history in southeast- ern Montana. Zoogeographically, this part of Montana supports a mammalian fauna composed of widespread, boreomontane, steppe, sonoran. Great Basin, and eastern species. Species with widespread distributions comprise the largest single group. LITERATURE CITED Alden, W. C. 1932. Physiography and glacial geology of eastern Montana and adjacent areas. U.S. Geol. Surv., Prof. Paper, 174:viii + 133. Allex, J. A. 1877. History of the American bison, Bison americanus. Ann. Rept. U.S. Geol. and Geogr. Surv. Territories, 9:443-587. Andersen, K. W., and J. K. Jones, Jr. 1971. Mammals of northwestern South Dakota. Uni\-. Kansas Publ., Mus. Nat. Hist., 19:361-393. Bailey, V. 1907. Wolves in relation to stock, game and the national forest reserves. Bull. U.S. Forest Service, 72:1-31. 1915. Revision of the pocket gophers of the genus Thomomys. N. Amer. Fauna, 39:1-136. 1927. A biological survey of North Dakota. Ihid., 49:vi + 1-226. Bauer, C. M. 1924. The Ekalaka lignite field, southeastern Montana. Bull. U.S. Geol. Surv., 751:231-267. Beck, W. H. 1958. A guide to Saskatchewan mammals. Spec. Publ. Saskatchewan Nat. Hist. Soc, 1:1-52. Beer, J. 1944. Distribution and status of the pronghorn antelope in Montana. Jour. Mamm., 25:4.3-46. BiRNEY, E. C, and R. P. Lampe 1972. Sagebrush vole (Lagurus curtatus) in South Dakota. Amer. Midi. Nat., 88:466. Browxx, L. N. 1967. Ecological distribution of six species of shrews and comparison of sampling methods in the central Rocky Moimtains. Jour. Mamm., 48:617-623. THE MAMMALS OF CARTER COUNTY, MONTANA 37 BXJECHNER, H. K. 1960. The bighorn sheep in the United States, its past, present, and future. Wildlife Monogr., 4:1-174. Cahalane, V. H. 1954. Status of the black-footed ferret. Jour. Mamm., 35:418-424. COUEY, F. M. 1946. Antelope foods in southeastern Montana. Jour. Wildlife Mgt., 10:367. Cowan, I. McT. 1940. Distribution and variation in the nati\e sheep of North America. Amer. Midi. Nat., 24:505-580. Custer, G. A. 1875. A report of the expedition to the Black Hills. Exec. Doc, Senate, 2nd Sess., 43rd Congress, 32:1-9. FiNLEY, R. B., Jr. 1969. Cone caches and middens of Tamiasciurus in the Rocky Mountain region. Pp. 233-273, in Contributions in mammalogy (J. K. Jones, Jr., ed.). Misc. Publ. Mus. Nat. Hist., Univ. Kansas, 51:1-428. Genovi^ays, H. H., and J. K. Jones, Jr. 1972. Mammals from southwestern North Dakota. Occas. Papers Mus., Texas Tech Univ., 6:1-36. Gill, J. R. 1962. Tertiary landslides, northwestern South Dakota and southeastern Montana. Bull. Geol. Soc. Amer., 73:724-736. Goldman, E. A. 1944. Classification of wolves. Pp. 387-507, in The wolves of North Amer- ica (S. P. Young and E. A. Goldman), Amer. Wildlife Inst., Wash- ington, D.C., .xvi -f 636 pp. Hall, E. R. 1951. A synopsis of the North American Lagomorpha. Univ. Kansas Publ., Mus. Nat. Hist., 5:119-202. Hall, E. R., and K. R. Kelson 1951. Comments on the taxonomy and geographic distribution of some North American rabbits. Ibid., 5:49-58. Henderson, F. R., P. F. Springer, and R. Adrian 1969. The black-footed ferret in South Dakota. South Dakota Dept. Game, Fish and Parks, Pierre, 37 pp. Hibbard, E. a. 1956. Range and spread of the grey and fox squirrel in North Dakota. Jour. Mamm., 37:525-531. Hoffmann, R. S., and J. K. Jones, Jr. 1970. Influence of late-glacial and post-glacial events on the distribution of Recent mammals on the Northern Great Plains. Pp. 355-394, in Pleistocene and Recent environments of the central Great Plains (W. Dort, Jr., and J. K. Jones, Jr., eds.). Spec. Publ. Dept. Geol., Univ. Kansas, 3:1-433. Hoffmann, R. S., and D. L. Pattie 1968. A guide to Montana mammals. . . . Univ. Montana, Missoula, x -|- 133 pp. Hoffmann, R. S., P. L. Wright, and F. E. Newby 1969a. The distribution of some mammals in Montana. I. Mammals other tlian bats. Jour. Mamm., 50:579-604. Hoffmann, R. S., D. L. Pattie, and J. F. Bell 1969b. The distribution of some mammals in Montana. II. Bats. Ibid., 50: 737-741. 38 OCCASIONAL PAPERS MUSEUM OF NATURAL HISTORY HOLLISTER, N. 1916. A systematic account of the prairie-dogs. N. Amer. Fauna, 40:1-37. Hooper, E. T. 1944. Additional records of the Merriam shrew in Montana. Jour. Mamm., 25:92. Howell, A. H. 1929. Revision of the American chipmunks (genera Tamias and Etitamias) . N. Amer. Fauna, 52:1-157. 1938. Revision of the North American ground squirrels, with a classifica- tion of the North American Sciuridae. Ibid., 56:1-256. Jackson, H. H. T. 1928. A taxonomic review of the American long-tailed shrews (genera Sorex and Microsorex). N. Amer. Fauna, 51:vi -f- 1-238. Jonas, R. J. 1966. Merriam's turkey in southeastern Montana. Tech. Bull., Montana Fish and Game Dept., 3:1-36. Jones, J. K., Jr. 1953. Geographic distribution of the pocket mouse, Perognathus fasciatus. Univ. Kansas Publ., Mus. Nat. Hist., 5:515-526. 1964. Distribution and taxonomy of mammals of Nebraska. Ihid., 16:1- 356. Jones, J. K., Jr., and F. R. Henderson 1963. Noteworthy records of foxes from South Dakota. Jour. Mamm., 44:283. Jones, J. K., Jr., R. P. Lampe, G. A. Spenrath, and T. H. Kunz 1973. Notes on the distribution and natural history of bats in southeastern Montana. Occas. Papers Mus., Texas Tech Univ., 15:1-12. Kellogg, G. E. (ed. ) 1938. Soils of the United States. Pp. 1019-1161, in Soils and Men, Year- book of Agriculture, U.S.D.A., xvi + 1232 pp. Koch, E. 1941. Big game in Montana from earlv historical records. Jour. Wildlife Mgt., 5:357-370. Krutzsch, P. H. 1954. North American jumping mice (genus Zapus). Univ. Kansas Publ., Mus. Nat. Hist, 7:349-472. KUCHLER, A. W. 1964. Potential natural vegetation of the conterminous United States. Spec. Publ., Amer. Geogr. Soc, 36: v + 1-39 + map +116 plates. KtTRTEN, B., and R. Rausch 1959. Biometric comparisons between North American and European mammals. Acta Arctica, Fasc. XI. E. Munksgaard, Copenhagen, 44 pp. Lampe, R. P. 1971. The mammals of southeastern Montana. Unpubl. M.A. thesis, Univ. Kansas, Lawrence, ii -\- 68 pp. Lillegraven, J. a. 1970. Stratigraphy, structure, and vertebrate fossils of the Oligocene Brule Formation, Slim Buttes, northwestern South Dakota. Bull. Amer. Geol. Soc, 81:831-850. LiNHART, S. B., and W. B. Robinson 1972. Some relative carnivore densities in areas under sustained coyote control. Jour. Mamm., 53:880-884. Long, G. A. 1965. The mammals of Wyoming. Univ. Kansas Publ., Mus. Nat. Hist., 14:493-758. THE MAMMALS OF CARTER COUNTY, MONTANA 39 McDaniel, L. L. 1967. Merriam's shrew in Nebraska. Jour. Mamm., 48:489-493. Miller, G. S., and R. Kellogg 1955. List of North American Recent mammals. Bull. U.S. Natl. Mus., 205:xii + 954. Nelson, E. W. 1909. The rabbits of North America. N. Amer. Fauna, 29:1-314. Pefaur, J. E., and R. S. Hoffmann 1971. Merriam's shrew and hispid pocket mouse in Montana. Amer. Midi. Nat., 86:247-248. Perry, E. S. 1962. Montana in the geologic past. Bull. Montana Bur. Mines and Geol., 26:vi-f- 1-78. Pfeifer, W. K., and E. A. Hibbard 1970. A recent record of the swift fox (Vulpes velox) in North Dakota. Jour. Mamm., 51:835. Preble, E. A. MS. List of the mammals of eastern Montana. On file, Dept. Zoology, Univ. Montana, Missoula, 12 pp. Raynolds, W. F. 1868. Journal of Captain W. F. Raynolds. Pp. 18-127, in Report on the exploration of the Yellowstone River . . . , Exec. Doc, Senate, 2nd Sess., 40th Congress, 77:1-174. [erroneously printed as 1st Sess.] Robinson, W. B. 1961. Population changes of carnivores in some coyote-control areas. Jour. Mamm., 42:510-515. Soper, J. D. 1961. Field data on the mammals of southern Saskatchewan. Canadian Field-Nat., 75:23-40. Spencer, A. W., and D. Pettus 1966. Habitat preferences of five sympatric species of long-tailed shrews. Ecology, 47:677-683. SWENK, M. H. 1941. A study of subspecific variation in the Richardson pocket gopher (Thomomys talpoidcs) in Nebraska, with description of two new subspecies. Missouri Valley Fauna, 4:1-8. Thompson, W. K. 1949. Predation on antelope. Jour. Wildlife Mgt., 13:313-314. Tryon, C. a., Jr. 1947. Entrance and migration of the Norway rat into Montana. Jour. Mamm., 28:188-189. Turner, R. W. 1974. Mammals of the Black Hills of South Dakota and Wyoming. Misc. Publ. Mus. Nat. Hist., Univ. Kansas, 60:1-178. Van Zyll de Jong, C. G. 1972. A systematic review of the Nearctic and Neotropical river otters (genus Liitra, Mustelidae, Camivora). Life Sci. Contrib., Royal Ontario Mus., 80:1-104. ViSHER, S. S. 1914. Report on the biology of Harding County, northwestern South Da- kota. Bull. South Dakota Geol. Surv., 6:1-103. University of Kansas Publications MUSEUM OF NATURAL HISTORY The University of Kansas Publications, Museum of Natural History, beginning with volume 1 in 1946, was discontinued with volume 20 in 1971. Shorter research papers formerly pub- lished in the above series are now published as Occasional Papers, Museum of Natural History. The Miscellaneous Publica- tions, Museum of Natural History, began with number 1 in 1946. Longer research papers are published in that series. Monographs of the Museum of Natural History were initiated in 1970. 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