Great Basin Naturalist
Volume 58 Number 1 Article 7
1-30-1998
Bats of the White and Inyo Mountains of California–Nevada
Joseph M. Szewczak University of California, White Mountain Research Station, Bishop, California
Susan M. Szewczak University of California, White Mountain Research Station, Bishop, California
Michael L. Morrison California State University, Sacramento, California
Linnea S. Hall California State University, Sacramento, California
Follow this and additional works at: https://scholarsarchive.byu.edu/gbn
Recommended Citation Szewczak, Joseph M.; Szewczak, Susan M.; Morrison, Michael L.; and Hall, Linnea S. (1998) "Bats of the White and Inyo Mountains of California–Nevada," Great Basin Naturalist: Vol. 58 : No. 1 , Article 7. Available at: https://scholarsarchive.byu.edu/gbn/vol58/iss1/7
This Article is brought to you for free and open access by the Western North American Naturalist Publications at BYU ScholarsArchive. It has been accepted for inclusion in Great Basin Naturalist by an authorized editor of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. Greal Basin Naturalist 58(1). © 1998, pp. 66-75
BATS OF THE WHITE AND INYO MOUNTAINS OF CALIFORNIA-NEVADA
Joseph M. Szewczak1,2, Susan M. Szewczak1, Michael L. Morrison3, and Linnea S. Hall3
ABSTRACT.-We surveyed bats throughout the White and Inyo Mountains ofCalifomia. and Nevada. From December 1990 to November 1996, we surveyed hibernating bats. and foraging bats from June 1992 to September 1996. The White-Inyo Range rests in a unique biogeographical junction between the Sierra Nevada. Mojave Desert,. and Creat Basin regions. Elevational gradients of 305-4340 m. combined with limited human development, further enhance the interest of natural history and faunal distributions in this range. We found 13 bat species in the course of2668 observa tions. Three of these species. the spotted bat (EtJ.derma maculatum), silver-haired bat (Lasionycteris noctivagans), and hoary bat (Lasiuros cinereus), have DO previous records from the White-lnyo Range. We found bats in all vegetation wnes except the alpine, 3500-4342 m. Despite an abundance of mines in this range, only Townsend's big-eared bat (Corynorhinus Wwnscndii) and the western small-footed myotis (Myotis ciliolobrum) used them routinely. Our data also indicated the im~rtanceofsurface water to bat populations in arid regions.
Key words: bats. Chiroptera, Great Basin, vegetation zones. habiMt, desert, and regions, water source. hibernation.
The White-Inyo Range rests in the junction characterize how each bat species uses avail of 3 faunal regions, the Sierra Province to the able mine resources. We report observations west, Mojave to the south, and Great Basin to from both foraging and hibernating bats. the east. Because this range rises abruptly on its Because the White-Inyo Range remains rela east and west sides, animals can readily access tively undisturbed habitat, this baseline may a variety of vegetation types over short linear prove useful for tracking long-term alterations distances. In addition to altitudinal differences, in environment, since many researchers con vegetation communities are enhanced by a vari sider bats to be sensitive indicators of environ ety of edaphic sites resulting from the range's mental change (Kunz 1982, McCracken 1986, high lithographic diversity (Elliot-Fisk 1986). Thomas 1988). These data also provide useful Despite this interesting biogeographical setting, comparisons for other ranges in the region. faunal distributions of the range have received Thousands of abandoned mines lie on public little attention. Morrison et a1. (1993) proVided and private lands (Shields et al. 1995). The the first thorough study of bird distributions importance of these mines as reservoirs for and habitat use in the White-Inyo Range. wildlife displaced from natural habitats has However, no systematic survey of bats and gained increasing recognition (Tuttle and Tay their habitat associations in these mountains lor 1994), and documenting patterns of mine has been undertaken. Hock (1963) summarized use by bats in the White-Inyo Range may results of a handful of general collecting trips prove useful for present and future manage from 1917 to 1958 that yielded some bat speci ment efforts. mens. This summary plus an unpublished manuscript from a field course at University of STUDY AREA California at Davis (Brosius et aI. ca 1974) con stitute all prior records. The White and lnyo Mountains extend for Our objectives were to provide a detailed approximately 175 km, forming a contiguous account of bat distributions throughout the range trending north-south and lying just east White-Inyo Range, assess how each species ofand parallel to the Sierra Nevada. The White utilizes the different vegetation zones available Mountains comprise the northern half, located to it along the range's elevational gradient, and within lnyo and Mono counties, California,
lUlli~j()I ofealifolnill White Mountllill Resean:h 5brtiOll. 3000 East Line St.• Bishop, CA 93514. 2AlJthor to w1lOl11 wrreqXlDdence should be addressed. JDeportmenl of Biologit'lll Scien<:a. Qaliw.....ia State Ulliv=;ity, Sacrwoento, CA 95819.
66 1998] BATS OF THE WHITE-INYO RANGE 67 and extending into Esmeralda County, Nevada, could observe bats foraging over open vegeta on their northern reach. The Inyo Mountains tion away from water, we could seldom capture extend to the south and lie entirely within Inyo sucb individuals. Therefore, most of our cap County, California. Elevational gradients span tures occurred at sources of water that from 300 m at the eastern base of the Inyo attracted bats (springs, pools, troughs, and Mountains in Saline Valley, California, to the stream corridors). We assume these records 4342-m summit ofWhite Mountain Peak, Cali represent bats observed foraging in the vicinity fornia. Annual precipitation varies from less of those water sources. than 10 em at the base ofthe range to approxi Foraging bats were captured over approxi mately 50 em along the northern crest of the mately 200 person-days in the field from May White Mountains (Oglesby 1985, Peterson through October 1990-1996. We used mist 1986). The Owens and Chalfant valleys (Cali nets or a harp trap set across open flyways near fornia) form a continuous valley separating the water sources. Four bats recorded in this study range from the Sierra on the west, while the were hand-captured from buildings at Deep east side of the range descends into a series of Springs College, Inyo County, California. We valleys. From north to south they are Fish Lake keyed each specimen to species (Ingles 1965, Valley, located within California and Nevada, Barbour and Davis 1969, Hall 1981), deter and Deep Springs Valley, Eureka Valley, and mined gender (and reproductive status if Saline Valley, all within California. Although female), and then released it. We typically we centered this survey on the White-lnyo maintained the nets from dusk to local 23:30 b Range, to fulfill our goal of assessing eleva depending upon activity, which normally trailed tional range we elected to extend our survey of offaround 22:30 h. Occasionally, we maintained foraging bats into the valley lloors at the base nets throughout the night but made few addi of these mountains. Bats foraging in these tional captures. areas may depend upon rocky outcrops and Although troublesome to differentiate in other features of the mountains for roosts and other regions, M. ciliolabrum and M. californi hibemaculae. cus were readily distinguished in the White Five primary vegetation zones occur in the Inyo Range. The White-Inyo M. ciliokzbr",n >"hite-lnyo Range along elevational gradients: has a distinctive straw-colored pelage with a (1) Mojave mixed desert scrub, characterized highly contrasting dark facial mask and ears. by the presence of creosote bush (Larrea tri The M. californicus we encountered has a chest denrota), 300--1200 m; (2) Great Basin desert nut brown pelage with much less contrast to scrub, where shadscale (A/riplex confe/iifolia) the facial mask and ears (Barbour and Davis is the most common species, 1200-2000 m; (3) 1969, Hall 1981). pinyon-juniper forest, predominantly single We also recorded bats we could identify leaf pinyon (Pinus monophylla) interspersed without capture. In 2 instances, with the aid of with Utah juniper (Juniperas osteospemw), binoculars, we identified roosting Brazilian 2000--2900 m; (4) bristlecone-limber pine for free-tailed bats (Tadarida brasiliensis). We then est (or subalpine), a mixture of these 2 trees counted individuals as they emerged in the (Pinus longaeva and Pinus flexilis), 2900-3500 evening. We similarly assessed a colony ofpal m; and (5) alpine, characterized by the absence lid bats (Antrozotls pallidus). The audible calls oftrees, 3500-4342 m. ofthe spotted bat (Ellderma maculatum) enabled species recognition without specialized equip METHODS ment and supplemented capture records for this species. Foraging Bats We considered bats on the wing from May Hibernating Bats to October to be foraging. Although active bats We considered inactive bats between the are occasionally seen during fu.ir 'winter weather months of November and March to be hiber (Barbour and Davis 1969), these lIights may nating. From December 1990 to November not necessarily be for foraging (Whitaker and 1996, we surveyed 2 natural caves and approxi Rissler 1989). We surveyed throughout the mately 260 mines for hihernating bats, working range in all vegetation zones between June approximately 125 person-days in the field. We 1992 and September 1996. Although we often entered the mine or cave and visually inspected 68 GREAT BASIN NATURAUST [Volume 58 all accessible reaches, paying particular atten TABLE 1. Compiled observations of bats in the White tion to crevices in the walls and ceilings. We lnyo Range, 1990-1997, with previous records shown in parentheses. Previous specimen number for M!lotis volans took care to minimize disturbance to bats and is inexact, as it was described as M many" from 3 locations other inhabitants by limiting direct light con (Museum ofVertebrate Zoology). tact and moving quietly through the mine or Number Number cave. Species determinations were made by observed observed noncontact inspection to avoid disturbance. Species foraging hibernating Fortunately, all species were identified easily Tadarida brasiliensis 1185 (5) in this way. M. ciliolabrum was often found Euderma macuwtum 91' 5-10 cm deep in crevices but was recognizable Corynorhinu-s townscndii 45 (2) 479 (13) by its size, pointed tragus, straw-colored fur, Antmzous pallidus 85 (4) and almost black facial mask (Barbour and Lasionycteris noctivagans 2 2 lAsiurtls cinereus 27 Davis 1969, Hall 1981). Using a mercury field Pipistrellw hesperus 410 (18) 4 thermometer +1°C accuracy. we recorded air Eptesicusfuscus 100 (4) I temperature in the immediate vicinity ofroost· Myotis et.'Otis 12 (3) ing bats. Myofis voWns 103 (14+) 1 Myotis californicus 15 (2) Previous Capture Records Myotis ciliolabrum 33 (4) 49 .\1.yotis lucifugus:f: . (1) We searched for previous capture records of Myotis yumanensis+ 24 (3) White-Inyo bats at the Los Angeles County TOTALS 2132 (60+) 536(13) Museum of Natural History (LACM), Museum "11ucc COIptUred ill mist nets, ~r re<:or elevation in reet _ fO(oglng range 2,000 .,000 6,000 8,000 10,000 12,000 1.,000 I ! I , , I ! , , , ! , _ hibernating range - - - Mojave mixed Gleat Basin plnyon-j Antrozous pallldu. • l ••lonycterls noctivagan, I L8siurus c;nereu. - Pipi.trellus heaperus lU II 7 Epteslcus #Uacus ---*., - lIyoti. evotls IIyoti. volana Afyotis californlcus "yolls cillo/"',um Mfati. lucilugu. I Myat;. yum.nens/, I , i i I i I i 1,000 2,000 3,000 4,000 elevation In meters Fig. 1. ELcvational distribution offor.tging and hibemotjng; b;tt.~ in the White-Inyo Range showing vcgctati,on 7..ones. Pass, California, this cavern extends approxi species within ,,1 mine. We never ohseIved M. mately 50 m inward with ceiling heights up to ciliolahrum hibernating together, hut C. town about 25 m. This cavern remains undisturbed sendii were observed in clusters as large as because it is protected by a locked gate and approximately 50 individuals. We observed only remote location and is relatively inaccessible 1 individual each of E. ftl8~'US, L. noctivag"'.." because of its vertical cntrance. However, fol and M. volans hibernating in mines. In mines lowing 4 visits over separate years, we obsetvcd below 1500 m, we encountered bats in approx only a single C. townsendii hibernating within imately 25% of mines >3 m in lcngth. Above it. A single C. townsendii was observed hibcr 1500 m elevation, approximately 50% of mines nating in a 2-m-deep natural pocket in a dolo > 3 m in length contained at least 1 bat. These mite formation in the southern end ofthe White estimates of mine use are based upon our gen Mountains (1890 m). On 2 occasions (5 Decem eral impressions only, because it was not possi ber 1991 and 18 February 1995), an active L. ble (or deemed safe) to enter every mine, Or to tWctivagans was found in a dormitory hallway survey every part ofthe mines we did enter. at Deep Springs College. Because oftheir con dition and the dates, we assumed they had Species Accounts been hibemating on the premises. All other 1adarida brasiliensis hibernation observations were from mines. We found C. townsendi.i and M. ciliJ:Jlabrtlffi T brasilien';', was found at the lower eleva hibernating in mines throughout the range. tions of the Inyo Mountains and southernmost These species: were obselved hibernating with· portion ofthc White Mountains (lower Cotton in about 40 em of each other. However, we wood Crcek, above Oasis Ranch, Mono Co., often encountered lone iodividuals of either Califnrnia; T5S R37E, Sec 33; 1600 m). We 70 GREAT BASIN NATURALIST [Volume 58 observed a dispersed colony of 1028 at the R37E, Sec 5; 1600 m), and 1 female on 25 July base ofMcElvoy Canyon on the east side ofthe 1992 at a concrete water trough at the north lnyo Mountains, lnyo Co., California (640 m). west end of Saline Valley Lake at 305 m (lnyo We describe this colony as "dispersed" because Co., California; TI4S R38E, Sec 27). We ob they roost in a series of overhanging ledges served 36 individuals exiting a maternity roost along the narrow canyon wall, rather than a at the base of the White Mountains in Deep single site. A perennial stream flows through Springs Valley (lnyo Co., California; 1705 m), the canyon below the roosts. We counted these and a single male carcass was found in a build bats on 26 July 1992 as they flew overhead ing at Oasis Ranch in Fish Lake Valley on the after emerging, heading in the direction of east side of the White Mountains (Mono Co., Saline Valley. This site appears vacant during California; T5S R37E, Sec 28; 1530 m). A winter. A crevice in a large boulder above the maternity colony of several hundred is known Deep Springs dairy (lnyo Co., California; T7S on the west side of the White Mountains, lnyo R36E, Sec 1; 1590 m) hosts more than 100 T Co., California (1710 m; Patricia Brown-Berry, brasiliensis for several weeks during the spring, personal communication). This bat is also known perhaps a stopover during migration. On 19 to roost in lava tube caves on the western slope August 1996 we found a small colony at the of the lnyo Mountains at approximately 1380 entrance ofa dolomite mine at the western base m (Denyse Racine, California Department of of the Inyo Mountains near the "shoreline" of Fish and Game, personal communication). The Owens Dry Lal Myotis evotis at the Lone '11'ee Creek headworks (Mono Co., vVe found AI. cvatis along the lower drain California; T3S R33E, Sec 33; 2070 m), also on ages of the White :Mountains and up through the west side of the '''hite Mountains. Three the pinyon-juniper zone. Our highest capture other females were captured along the lower for this species occurred on 8 July 1993 at 2470 portion of Cottonwood Creek on separate m along Chiatovich Creek (Esmeralda Co., occasions (Mono Co., California; T5S R37E, Nevada; TIS R33E, Sec 35), where we cap Sec .33; 1660 m). tured 1 male and 1 female; however, the MVZ Myotis ciliolabrurn lists a 1954 record from Cottonwood Creek (White Mountains, Mono Co., California) at Together with C. townsendii, M. ciliolabrum 2895 m. A female M. evotis was captured was the only other bat we commonly found beside a storage building at Deep Springs Col hibernating in the White-[nyo Range. Our lege (Inyo Co., California; T7S R36E, Sec I; highest hibernating observation of M. cilio 1600 m) on 4 September 1992. All other cap labrnm occurred on 12 February 1994 at 2500 hIres were at water sites. m in the White Mountains (Inyo Co., Califor nia), and our lowest was on 23 December 1990 A1.yotis volans at 1710 m in a small mine on the northwest M. valans was well distributed throughout slope of Deep Springs Valley (Inya Co., Cali the vVhite-Inyo Range in the Great Basin fornia). We usually found this bat well up into a scrub and pinyon-juniper zones. vVe observed crevice and hibernating alone, even among a a single hibernating M. vo[am during this sur group of tunnels. However, we f()Und ] 0 dis vey in a mine at the north end of the White tributed through a mine in rvf arblc Canyon on Mountains on 31 Jannary 1993 (Esmeralda Co., the east side of the Inyo Monntains (Inyo Co., Nevada; 2770 m). Onr highest foraging obser California; 2260 m). We found M. ciliolabrum vation ofM. valans occurred at Mexican Spring foraging throughout the Great Basin scrub and toward the southern end of the 1nyo Moun pinyon-juniper zone of the range. Our highest tains at 2740 m (Inyo Co., California; Tl5S foraging observation for this species was a R38E, Sec 34); however, the MVZ also lists a male captured at Mexican Spring toward the 1954 record of "muny" specimens of this bat southern end ofthe Inyo Mountains on 22 July from Cottonwood Creek (White Mountains, 1992 at 2740 m (Inya Co., California; Tl5S Mono Co., California) at 2895 m. Our lowest R38E, Sec 34); the lowest was a pregnant capture of this hat \vas a male netted on 25 female we captured over the runoff of a spring August 1992 at a road stream crossing in Silver on the eastern shore ofOwens Dry Lake (Tl7S Canyon on the west side of the ""hite Moun R38E, Sec 9; 1080 m) on 30 May 1996. tains at 1410 m (Inyo Co., California; T6S R34E, Myot;, lucifugus Sec 24). On 19 June 1996 we captured a non reproductive female over a small pond on the We did not encounter M. lucifugus during eastern shore ofOwens Dry Lake ncar the town our survey, hut the LACM lists a specimen of of Keeler (Inyo Co., California; T17S R:38E, M. lucifugus from lower vVyman Canyon in the Sec 5; 1080 m). southern 'Vhite Mountains from Mav, 1972 (Inyo Co., California; T6S R36E, Sec 23; 1740 "Alyotis californicus m). However, we believe a discrepancy exists We captured M. californicus at 4 sites in the regarding the A1.yotis species in the Owens White Mountains along its lower slopes in the Dry Lake area. Our comments in this regard Great Basin scrub zone and up into the begin are in the Discussion below. ning of the pinyonMjuniper zone. On 24 July Myotis yumanensis 1995 and 3 August 1995, a female M. califomi cus was found roosting during the day in a "'e captured 24 specimens of this bat along classroom at Deep Springs College (Inya Co., the eastern shore of Owens Dry Lake on the California; T7S R36E, Sec 1; 1600 m). On 25 southern end ofthe Inyo Mountains. The most August 1992 we captured a female at a road prolific activity occurred over a small pond stream crossing in Silver Canyon on the west several km north of the town of Keeler (Inyo side of the While Mountains (Inyo Co., Cali Co., California; TI6S R38E, Sec 31; 1080 m). fornia; T6S R34E, Sec 24; 1410 m) ,md 2 males There we captured 8 lactating females and 1 1998] BATS OF TilE WlIITE-INYO RANGE 73 volant juvenile male on 9 July 1996. At another fers. Successfully utilizing such diflerent envi small pond closer to Keeler, \ve captured 1 lac ronments as Mojave mixed desert scrub and tating and 1 pregnant female on 19 June 1996 pinyon-juniper forest suggests an ability to (Inyo Co., California; TI7S R38E, Sec 5; I080 exploit a variety offoraging strategies and prey m). These records indicate the presence of a selection. Such adaptability may seem surpris maternity roost in the Keeler vicinity. On 24 ing in view of evidence that this species re August 1995 we netted a female at the Sulfate mains threatened over much ofits original range Well on Owens Dry Lake (Inyo Co., California; (former C2 species and California species of Tl7S R38E, Sec 18) and a male and a female special concern). However, this result is consis w on 14 September 1995 near the eastern Owens tent with other studies indicating that roost Lake margin (Inyo Co., California; TI6S R37E, disturbance may be a more decisive factor in Sec 26). We also observed these bats flying to this bat's decline than habitat disturbance (Pier foraging sites on tlle lake bed at dusk, presum son and Rainey 1994). The remoteness and low ably heading out from roost sites east of the human population density of the White-Inyo lake, at the base ofthe Iuya Mountains. Range reduce human disturbance as a factor. However, the remoteness of this range also DISCUSSION provides relatively undisturhcd foraging habi tat; thus, the relative effect of roost vs. habitat Of the 13 bat species we encountered in disturbance cannot be separated. In fact, the this survey, none specialized in any of the 5 situation in the White-Inyo Range could also vegetation zones of the White-Inyo Range. All be interpreted to suggest that C. townsendii species overlapped with at least 1 other zone, requires undisturbcd roosts and foraging habi although for L. noctivagans, L. cinereU8, and tat to thrive. Interestingly, the modern White M. californiws the overlap from the Great Basin Iuyo population of C. townsendii may exceed desert sClub into the pinyon-juniper ZOlle was prehistoric numbers. Humphrey and Kunz limited. E. nwculatum, C. townsendii, E hespe (1976) concluded that this bat is a capable colo rus, E. fuscus, and M. volans were all found foraging over 3 zones. Including the hibernat nizer. It naturally roosts in caverns, which ing observations, c. townsendii extended its rarely occur in this range. Because of this, C. range through all zones in which we observed townsendU has only recently begun roosting in bats. We observed only E. jilSeuS and M. volans the area, basically within the many mines cre foraging in the higher bristlecone-limber pine ated iu the last century. zone, compared with 9 foraging species in the vVe should note that our survey shows a bias pinyon-juniper zone. In contrast, Morrison et toward activity in riparian corridors and other aJ. (1993) observed 61 bird species in the areas with watel~ as those were the only places bristlecone-limber pine zone, 3 more than in in which we could eflectively capture foraging the pinyon-juniper zone. The reduced bat for bats. With this bias, the comparative lichness we aging activity in the bristlecone-limber pine measured in the Great Basin desert scrub zone zone may result from the diurnal vs. nocturnal may instead depict the richness of a wetland habits ofbirds vs. bats and these bats' exclusive environment in the milder climate ofthis lower insect diet. The higher elevation of tl,e bristle elevation zone compared with the others. Thus, cone-limher pine zone elicits colder nocturnal it may not accurately reflect general compara temperatures, causing impoverished nocturnal tive trends in species richness in these zones. insect activity (Wellington 1945). Graham (1983) Bats typically sip water by skimming over it found a similar decrease in hat species moving (Kunz 1982) and thus require water sources up an elevational gradient in the Peruvian with an open surface. We visited point water Andes. sources in the Inyo Mountains with such con C. townsendii foraged in 3 different vegeta stant bat activity that we did not risk setting tion communities (Fig. 1). This bat is a known mist nets too ncar them. Because such water lepidopteran specialist (Barbour and Davis 1969, sources are the only ones available for many Clark et aJ. 1993). While some lepidopteran kilometers in any direction, it seems clear that species may be found throughout these vegeta entire populations depend upon these isolated tion communities, the overall species composi sources. vVe recommend that wildlife manage tion among these communities most likely dif- ment planners consider the impacts of such 74 GREAT BASIN NATURALIST [Volume 58 water sources upon bats, in addition to other of M. yumanensis (Barbour and Davis 1969, wildlife. For example, the seemingly harmless Herd and Fenton 1983). Harris's conclusion cessation of water flow to an old trough may was based solely upon 10 museum specimens, profoundly affect bat populations in a large a "few" study skins, and specimens in alcohol. surrounding area. Evaluation of existing and «Few specimens of M. I. relictus are undam planned water sources with consideration of aged, resulting in a less than ideal sample size bat needs could do mucb to enhance bat popu for statistical analysis." Harris, noting the pale lations in arid regions. coloration of the Keeler specimens, accounted Overall, C. towtUiendii and M. ciliolabrum for it by stating that "selection at the lower ele accounted for nearly 99% of all bats found in vations could easily have produced the level of mines, with C. townsendii comprising about paleness seen at Keeler." Lending further con 89%. Because both E. fw;CWJ and M. VOW-tUi are fusion, Harris identified 3 ofthe 10 Owens Lake regarded as regular mine users (Tuttle and Tay museum specimens as M. yumanensis. What lor 1994), the single hibernation sightings for ever the taxonomic resolution of this debate, these bats contrasted with our foraging obser all bats we recorded as M. yumanensis are a vations of these species. This indicated that morphologically similar population. A defini either their White-Inyo hibernaculae remain tive resolution of the species designation for undiscovered or they typically leave the area to this population may await DNA analysis. hibernate. OUf observation of L. noctivagans M. thysanodes (fringed myotis) was also ab hibernating in a mine is of note because this sent from this survey but has a range described species has rarely been found to use mines as to include the White-Inyo Range (Hall 1981). hibernaculae (Barbour and Davis 1969, AJten Barbour and Davis (1969) described M. thy bach and Pierson 1994). sanodes as preferring pinyon-juniper forests, Noticeably absent from this survey was M. making their absence from the White-Inyo lw;ifugw;, whose range is described as encom Range more conspicuous. However, Hall and passing the White-Inyo Range (Hall 1981). Kelson (1959) mentioned that it does not seem Perhaps the sparse timber of the range does to be common anywhere in its range and that it not meet the requirements of M. lucifugw;, seems to prefer caves, which seldom occur in which is described as preferring timbered areas the range. Thus, in contrast to C. townsendii, (Hall and Kelson 1959). The LACM record from which has apparently moved into the range by lower Wyman Canyon may be representative exploiting many available mines in place of ofoccasional forays this species may make into natural caves, M. thysarwdes may not be as the White-lnyo Range from the Sierra Nevada adaptable to mines or may move more slowly to the west. The thoroughness of the present into previously unused areas. survey would have likely encountered this More than a dozen bat species inhabit the species if it routinely inhabited the White White-Inyo Mountain Range, attracted by a Inyo Range. variety of natural and artificial conditions. Our The Owens Lake myotid that we recorded data indicate influences in species distribution as M. yumanensis is described by Harris (1974) from vegetation zones, availability ofwater, and as the subspecies M. lw;ifugw; relictw;, with mines. Further work using noncontact census Keeler as the type location. However, consis methods will be required to assess the impact tent with earlier descriptions but contrary to of vegetation zones away from water. Today the Harris, we prefer to maintain its designation as White-Inyo Range serves as a refuge for bats, M. yumanensis based upon the dull and pale and careful management of water, mines, and pelage and ligbt-colored ears cbaracteristic of other resources may continue this role indefi M. yumanensis, and our field observations in nitely. which its habitat and foraging behavior are more consistent with M. yumanensis than with ACKNOWLEDGMENTS M. lw;ifugw;. The Keeler/Owens Dry Lake locale is unforested, an uncharacteristic habitat We could not have completed the scope of for M. lucifugtts. From our observations these this survey without the invaluable support of bats foraged almost exclusively over the scat Kathy Noland and the Inyo National Forest, tered open water along the margin of Owens Terry Russi and the Bureau of Land Manage Dry Lake, flying just over it, a strategy typical ment, and Elizabeth Phillips and Dave Trydahl 1998] BATS OF THE WHITE-!NYO RANGE 75 and the University of California White Moun HUMPHREY, S.R., AND TH. KCNz. 1976. Ecology ofa Pleis tain Research Station. We thank 2 anonymous tocene relict, the western big-eared bat (Plecotus townsendii), in the southern Great Plains. Journal of reviewers for their insights that contributed to Mammalogy 57:470-494. the manuscript. We also acknowledge Alex INGLES, L,G. 1965, Mammals of the Pacific States. Stan Berger, David Galbraith, Noah Hamm, and ford Universitv Press, Stanford, CA. 508 pp. Brendan Taaffe, and thank them for their help. KUNz, T.H. 1982. E~ology of bats. Plenum Press, New York and London. 425 pp. MCCRACKEN, G. 1986. Why are we losing our Mexican LITERATURE CITED free-tailed bats? Bats 3:1-4. MORRISON, M.L., L.S. HALL, J.J. KEANE, A.J. KUENZI, AND ALTENBACH, ].5., A:;.ID E.D. PIERSON. 1994. Pages 7-18 in J. VERNER. 1993. Distribution and abundance of birds The importance of mines to bats: an overview. Bats on the White Mountains, California. Great Basin Nat and Mines 1994 \iVorkshop Proceedings, Biological uralist 53:246-258. Resources Research Center, University of Nevada, O'FARRELL, M.J., AND w.G. BRADLEY. 1970. Activity pat Reno. terns of bats over a desert spring. Journal of Mam~ B.>l.RBOUR, R.W, AND W.H. DAVIS. 1969. Bats of America. malogy 5U8-26. University ofKentucky Press, Lexington. 286 pp. OGLESBY, RJ. 1985. Analysis ofwinter-season precipitation BROSIUS, AG., G. ERWIN, A. GLICKEN, P KIMSEY, AND totals and variations across the White Mountains 1: NIELSEN. No date (ca 1974). A wildlife survey of region of California-Nevada. Unpublished research the W"hite and Iuya Mountains. Unpublished manu paper, University of California, Davis, Geography script, University ofCalifornia, Davis. Unnumbered. Department. 15 pp. ClARK, B.S., D.M. LESLIE, JR" AND 1:5. CARTER. 1993. For PETERSON, A.M. 1986. The distribution and ecology of aging activity of adult female Ozark big-eared bats deciduous tree species in the \Vhite Mountains, (Plecotus townsendii ingens) in summer. Journal of CA-N\~ Unpublished master's thesis, University of Mammalogy 74:422-427. California, Davis, Geography Department. ELLIOT~FISK, D.L.1986. Quaternary dynamics of the White PIERSON, E.D., AND W.E. RAINEY. 1994. The distribution, Mountains. Pages 47-50 in C.A, Hall, Jr., and D.J. status, and management of Towsend's big-eared bat Young, editors, Natural history of the White-Inyo (Corynorhinus townsendii) in California. Report to Range, eastern California and 'western Nevada, and California Department ofFish and Game. high altitude physiology. \Vhite Mountain Research SHIELDS, D,J., T.C. BROWN, AND D.D. BROWN. 1995. Dis~ Symposium, Volume 1, University of California, Los tribution ofabandoned and inactive mines on national Angeles. Forest SelVice lands. USDA Forest Service General GRAHAM, G.L. 1983. Changes in bat species diversity along Technical Report RM-GTR~260. 195 pp. an elevational gradient up the Peruvian Andes. Jour THOMAS, D.W. 1988. The distribution of bats in different nal of Mammalogy 64:559-571. ages of Douglas-fir forests. Journal of Wildlife Man HALL, E.R 1981. The mammals of North America. 2nd agement 52:619-626. edition. Wiley, New York. 1181 pp. TUTTLE, M.D., AND A.R TAYLOR. 1994. Bats and mines. HALL, E.R, AND K.R KELSON. 1959. The mammals of Bat Conservation International, Austin, TX. 42 pp. North America. Volume 1. Ronald Press Co., New 'WELLINGTON, \~~G. 1945. Conditions governing the distri York. 625 pp. bution of insects in the free atmosphere. Canadian HARRIS, A.H. 1974. Myotis yumanensis in interior south~ Entomologist 77:7-15. western North America, with comments on Myotis WHITAKER. J.O., Jr., AND L.J. RISSLER. 1989. Do bats feed lucifugus. Journal ofMammalogy 55:589-607. in 'winter? American Midland Naturalist 129:200-203. HERD, RM., AND M.B. FENTON. 1983. An electrophoretic, morphological and ecological investigation of a puta Received 18 March 1996 tive hybrid zone between Myotis lucifugus and M. Accepted 14 July 1997 yumanensis (Chiroptera: Vespertilionidae). Canadian Journal ofZoology 61:2029-2050. HOCK, RJ. 1963. Mammals ofthe \Vhite Mountain Range, California. White Mountain Research Station Publi~ cations, Berkeley, CA. 5 pp.