Bat distribution and hibernacula use in west central Nevada

We captured 299 individuals of 11 bat species in mist-nets at 18 water sources in west central Nevada from June through August 1994. Myotis ciliolubrum, Pipistrellus hesperus, M. californicus , and Corynorhinus townsendii were the most common species captured. These species are apparently broadly distributed throughout west central Nevada, occurring in a variety of habitat types. We captured Euderma maculatum at 2 localities. These represent the 1st known records of this species in Esmeralda County, Nevada. Mine adits were surveyed for hibernating bats from December 1994 through February 1995. We determined the presence of 3 hibernating species: C. townsendii, M. ciliolabrum and P. hesperus . Bats were present in 19 of 70 mines (27%) we surveyed at elevations ranging from 1500 m to 2460 m. C. townsendii was the most common species encountered. Our study provides some much-needed baseline data on bat distribution and use of mines for hibernacula in west central Nevada.     

Bats associated with inactive mines in the Great Basin

We surveyed bats using echolocation calls near inactive mines in the western Great Basin from 2003 to 2007. We identified 14 species of bats during our surveys, with Myotis lucifugus and Lasionycteris noctivagans found at 9 sites and Myotis evotis and Tadarida brasiliensis at 7 sites; all other species were found at less than one-half of the sites. Euderma maculatum, a state-protected species in Nevada, was recorded at 2 sites. Our work provides information that will be useful in managing bat habitat, especially with regard to mining activities.     

Distribution, foraging behaviour, and capture results of the spotted bat ( Euderma maculatum ) in central Oregon

The spotted bat ( Euderma maculatum ) has been virtually unknown in Oregon despite the existence of potential habitat in many areas of the state. In 2002 and 2003 we searched for spotted bats along the John Day, Deschutes, and Crooked Rivers and at a remote dry canyon southeast of the city of Bend in central Oregon. The species was documented through the use of mist-nets, a bat detector, and recognition of audible spotted bat calls. Spotted bats were found at 11 locations in 6 Oregon counties. Nightly activity patterns of spotted bats were unpredictable. Spotted bats were found in 78% of search areas but on only 48% of survey nights. We observed spotted bats foraging above fields and low upland slopes adjacent to rivers and creeks and along the rims of cliffs. Estimated flying heights of spotted bats ranged from 3 m to 50 m aboveground. The species was difficult to capture and was captured only after considerable experimentation with methods and materials. Three spotted bats were captured toward the end of the project in 2003 and accounted for only 0.5% of all bats captured during the study. Although we attached radio transmitters to 2 spotted bats, we found no roost locations. We believe additional spotted bat surveys in Oregon are warranted, especially in higher-elevation habitats, but recommend that to increase their effectiveness, surveys accommodate the unique foraging behavior of the species.     

Habitat affinities of bats from northeastern Nevada

Bat surveys were completed in 6 habitat types in eastern Nevada between 1980 and 1994. Twelve species of bats and 578 individuals were identified from 33 trap localities in 144 trap nights. There were weak correlations between bat species richness and January maximum temperatures (0.728, P P Antrozous pallidus (from central Nye County north to the Nevada-Idaho border, approximately 450 km), Tadarida brasiliensis (approximately 350 km north), and Pipistrellus hesperus (approximately 350 km north). Also, the presence of Lasionycteris noctivagans, Lasiurus cinereus , and Corynorhinus townsendii was confirmed.     

Bats along the Republican River and its tributaries in southwestern Nebraska: distribution, abundance, and reproduction

Thirteen species of bats occur in Nebraska, but limited information is available on those inhabiting southwestern parts of the state. We investigated the distribution, abundance, and reproductive activity of bats in 5 counties in extreme southwestern Nebraska (Chase, Hays, Dundy, Hitchcock, and Red Willow). From April 2007 to April 2008, we deployed mist nets on 15 occasions at 8 localities over the Republican River and its tributaries. We captured 100 individuals representing 5 species, including the evening bat ( Nycticeius humeralis ), eastern red bat ( Lasiurus borealis ), hoary bat ( Lasiurus cinereus ), big brown bat ( Eptesicus fuscus ), and silver-haired bat ( Lasionycteris noctivagans ). All species raised young in this region of Nebraska, except L. noctivagans , which was documented only during migration. Lactating females of N. humeralis captured on 15 June and volant young captured on 23 June extend known dates of reproductive activity for this species in the state, and an adult female captured on 30 April represents the earliest seasonal record of this species from Nebraska. Our records of evening bats also extend the known distribution of this species farther west in Nebraska than previously reported. Changes in land use throughout the Great Plains during the last century have altered many habitats, such as gallery forests associated with rivers, and distributions of mammals, including bats, have shifted to reflect those ecological changes.     

Influence of water size and type on bat captures in the lower Sonoran Desert

We compared bat use by mist-netting at 4 different types of wildlife water developments in southwestern Arizona during summer 2000 and 2001. Scaling our results by netting effort, we caught bats more frequently and observed higher species diversity at tinajas (modified natural rock pools) with larger open-water area compared with ""guzzler"" type water developments that had less open water and more obstacles to bat flight. We caught the fewest bats at guzzlers with buried concrete vault drinkers, which impede bat access and have the smallest areas of open water. Water development designs that minimize evaporative water loss by reducing the amount of open water apparently reduce use by bats in this area.     

New record of the bat Plecotus phyllotis from Utah

In June 1974 a scrotal male Mexican big - eared bat ( Plecotus phyllotis ) was netted near Hurricane, Utah. This account represents the third report of the species from Utah and extends the range approximately 330 km west of previous accounts. Adjacent state records are located approximately 64 km to the southeast in Arizona and 80 km southwest in Nevada.     

Local distribution and foraging behavior of the spotted bat ( Euderma maculatum ) in worthwestern Colorado and adjacent Utah

This study investigated local distribution and foraging behavior of the spotted bat ( Euderma maculatum ) in Dinosaur National Monument, Colorado-Utah, by monitoring audible echolocation calls. The occurrence of this species was verified in a variety of habitat types in canyon bottoms and other relatively low elevation sites, indicating that the animals were widely distributed and locally common in the area. Foraging spotted bats concentrated flight activity in the open-air space above meadows occasionally exploited near-canopy habitat (within 8 m of foliage). Bats began to forage shortly after dark, and activity levels were relatively constant throughout the night. Foraging spotted bats attacked airborne prey every 2.15 min on average. Consistent with published observations, spotted bats maintained exclusive foraging areas. Distinct vocalizations indicating agonistic encounters occurred when a bat encroached on the foraging area of a conspecific.     

Springtime movements, boost Use, and foraging activity of Townsend's big-eared bat ( Plecotus townsendii ) in central Oregon

Seasonal movements, roost-site fidelity, and foraging activity patterns are largely unknown for western populations of Townsend's big-eared bat ( Plecotus townsendii ). We used miniature radiotelemetry units to track springtime movements of six bats inhabiting forested lava flows in central Oregon, and found that bats moved up to 24 km from hibernacula to foraging areas. Individual bats returned to the same foraging area on successive nights but shifted to different areas in presumed response to changes in insect availability. Both sexes apparently use a series of interim roost sites between emergence from hibernation and the time females enter into maternity colonies, with little individual fidelity to these sites. In regions characterized by extensive lava-flow topography, suitable daytime roosts are numerous and dispersed over a large area, allowing bats to move relatively great distances to locate foraging ranges. Hence, the actual area of concern for effective management of individual populations can be considerably larger than indicated solely by locations of hibernacula and maternity caves of this declining species.     

An Erigeron from Nevada and a Penstemon from Idaho

Described as new species are Erigeron cavernensis Welsh & Atwood from the Schell Creek Range and Currant Mountain, White Pine County, Nevada, and Penstemon idahoensis Atwood     

New records of bats (Chiroptera: Mammalia) from Malawi,east-central Africa,with an assessment of their status and conservation

This paper reports 97 new species-locality records of bats from Malawi. Of particular interest are four species of bats (Rhinolophus swinnyi, Triaenops persicus, Eptesicus flavescens, Tadarida nigeriae) which have not been recorded previously from Malawi. The relative status of bats in Malawi was estimated and the species were placed in five categories ranging from ‘rarely-recorded’ to ‘very commonly-recorded’. Of the 59 species of bats known to occur in Malawi, 28 are rarely-recorded in Malawi. The relative status and species-locality records of bats were analysed to assess which species, and which localities, need special conservation effort. Seventeen species which are rare throughout their ranges in Africa as well as being rarely-recorded or seldom-recorded in Malawi, are considered to require special effort. Checklists of bats are given for 11 localities, including Liwonde NP in the Upper Shire Valley (29 spp.), two localities on the Shire Highlands (28, 22 spp.), Thyolo on the boundary between the Shire Highlands and Phalombe Plain (22 spp.), and Chiromo in the Lower Shire valley (30 spp.), which have particularly rich bat faunas. Localities in need of urgent conservation effort include Ntchisi FR in the Central Region, and Chiromo. Ninety-two percent of the species of bats known to occur in Malawi have been recorded from the Southern Region. Most of these species will probably continue to survive in southern Malawi provided that the National Parks (especially Liwonde NP) are maintained and well-managed, and there is no further destruction of the indigenous vegetation at Chiromo and Thyolo, and on the Shire Highlands.     

Biogeographic and taxonomic relationships among the mountain snails (Gastropoda: Oreohelicidae) of the central Great Basin

Described here are 4 species of mountain snails, Oreohelix , isolated on mountains in the central Great Basin of Nevada and Utah since the end of the Pleistocene. Forty-three mountains were searched during an 18-year period, resulting in 24 mountains found with no oreohelicids present. One population, Oreohelix loisae (19 mm to 23 mm in shell diameter), is described here as a new species related to, but geographically isolated from, the species Oreohelix nevadensis (17 mm to 22 mm diameter). Oreohelix loisae is present only in the Goshute Mountains while O. nevadensis is represented in 3 geographically adjacent ranges in the central Great Basin. These 2 species are possibly related to the Oreohelix haydeni group from the northern Wasatch Range. The subspecies Oreohelix strigosa depressa (15 mm to 21 mm diameter) is present on 11 ranges from western Utah west to east central Nevada. This subspecies is closely related to populations found today in the northern Wasatch Mountains of Utah. The smallest species in diameter (8 mm to 14 mm), Oreohelix hemphilli , is centered in the central Great Basin and found on 16 ranges often in sympatry with 1 or 2 of the larger conspecifics. Both qualitative and quantitative information on shell characters and soft anatomy is provided here for these 4 species. Shell characters, soft anatomy, geographical isolation, and statistical analysis suggest that 4 distinct species inhabit the central Great Basin today. Xeric and calciphilic species include O. hemphilli and O. loisae , while O. strigosa and O. nevadensis typically are associated with permanent water and both metamorphic and limestone mountains.     

Conservation, status, and life history of the endangered White River spinedace, Lepidomeda albivallis (Cyprinidae)

Lepidomeda albivallis (White River spinedace), a fish species endemic to the White River, Nevada, appeared headed toward extinction. In 1991 only 1 population remained, and it comprised fewer than 50 individuals in a 70-m stream reach. We monitored population recruitment and distribution and studied life history and habitat use from 1993 through 1998. We determined that L. albivallis was not reproducing and was continuing to decline, and as an emergency measure we relocated the population (14 in spring 1995 and 6 in spring 1996) downstream 200 m to a secure habitat that we judged more favorable for reproduction. The relocated population reproduced, and by September 1998 it had increased to 396 individuals that inhabited more than 1 km of stream including both pond and stream habitats. In streams they oriented near the bottom but frequently moved up in the water column to strike at drift items. Gut analysis of museum specimens indicated L. albivallis is omnivorous but feeds primarily upon aquatic invertebrates. Conservation of L. albivallis will require reestablishing additional populations within its former range.     

Co-occupancy of a den by a pair of Great Basin black bears

An adult male and an adult female black bear ( Ursus americanus ) were found in the same den in the Carson Range of the Sierra Nevada in Nevada. Co-occupancy of dens is very rare, and such behavior has never been previously reported for adult bears of opposite sex.     

Spotted bats ( Euderma maculatum ) from Mt. Taylor, New Mexico

The spotted bat ( Euderma maculatum ) is an elusive and rarely captured species in western North America. In the United States, it is known from 12 western states. In New Mexico, few individuals have been reported in recent years, and multiple individuals are known from 9 of 12 capture sites. This study reports on additional captures of E. maculatum from Mt. Taylor (Cibola County) for 2 consecutive summers and includes evidence of a reproducing population in the area. On 30 June/1 July 2006, I captured 4 individuals of E. maculatum , including a lactating female, and on 5 June 2007, I captured a nonreproductive female. The flight of this species was directional and deliberate; I captured 5 of 6 spotted bats that came low over the earthen pond. This study demonstrates how human-made sources of water in an arid region provide opportunities for many species of bats to drink.     

Current status of cutthroat trout subspecies in the western Bonneville Basin

Recent discoveries of native cutthroat trout populations in desert mountain ranges on the western fringe of the Bonneville Basin have prompted intensified management efforts by state and federal agencies. Analysis of Snake Valley cutthroat specimens in Trout Creek, Deep Creek Mountain Range, Utah, indicate this is a pure strain of the trout which once inhabited Pleistocene Lake Bonneville and which was thought to be extinct in Utah. The Snake Valley cutthroat is similar to Salmo clarki utah of the eastern Bonneville Basin; however, electrophoretic and morphomeristic analysis show unique genetic differences brought about by long - term isolation (8,000 years) from the remainder of the Bonneville Basin cutthroat. This cutthroat is a common ancestor to several other limited cutthroat populations within the basin in Nevada. In May 1977 the BLM withdrew from mineral entry about 27,000 acres within the Deep Creek Mountains for protection of this salmonid cutthroat and other unique resources on the range. Results of 1977 stream surveys on the Pilot Peak Mountain Range, Utah, indicate the presence of the threatened Lahontan cutthroat, Salmo clarki henshawi, in one isolated stream.     

Roost sites of the silver-haired bat ( Lasionycyeris noctivagans ) in the Black Hills, South Dakota

We investigated the roosting ecology of silver-haired bats ( Lasionycteris noctivagans ) in the Black Hills, of western South Dakota. Using radiotelemetry, we located 39 roosts, 10 of which were maternity aggregations containing 6 to 55 bats. The roosts were mostly in ponderosa pine ( Pinus ponderosa ) snags that averaged 39 cm diameter at breast height. Solitary bats preferred roosting under loose bark or in crevices in trees, regularly moving among trees. All maternity aggregations were found in tree cavities, primarily those created by woodpeckers. Roost trees were located in patches of forest with relatively high snag densities, about 21 snags/ha. This study suggests that snags play an important role in maintain silver-haired bat populations in ponderosa pine ecosystems.     

Roosting behavior of the Mexican free-tailed bat ( Tadarida brasiliensis ) in a highway overpass

A colony of Mexican free-tailed bats ( Tadarida brasiliensis ) roosting in an interstate highway overpass in Belton, Bell County, Texas, was studied weekly from 28 June to 21 November 1996 (except for the week of 4 July). We examined 2 aspects of roosting behavior: site-specific fidelity to locations within the roost and gender-related segregation within the roost. Colony estimates based on guano production showed a marked decrease in the number of bats from 19 to 26 July; many of these departing bats were adult females. No female bats sampled after this interval were pregnant. Male bats outnumbered females on nearly all sampling occasions. Throughout the study, one section of the roost was dominated by males, ranging from 83% to 100% of total bats. The majority of bats recaptured at least once were faithful to specific locations within the roost, and more than 70% of bats recaptured multiple times were faithful to specific roost locations.     

Effects of habitat type and degradation on avian species richness in Great Basin riparian habitats

The overwhelming majority of bird species in the Great Basin region are found in riparian habitats. However, most previous research on the impact of change in habitat condition through degradation on these bird communities failed to account for the large intersite differences, in both habitat type and extent of degradation. We examined songbird communities in 4 riparian habitat types (meadows, willow-birch-, and aspen-dominated forest stands) during summers 1994 (last year of a 7-yr drought) and 1995 (following the 6th wettest winter recorded) in the Toiyabe Mountain Range of central Nevada. Habitat degradation significantly influenced bird species richness in riparian areas, but the impact was dependent upon habitat type. While meadow bird communities were affected adversely by habitat degradation, with significant drops in species richness on degraded sites, bird species richness in forested riparian habitats was consistently greater on degraded sites. Data for the 6 most common species seen during our study indicated that degradation may have influenced distribution of American Robins ( Turdus migratorius ) and Yellow Warblers ( Dendroica petechia ), but habitat type was the best predictor of abundance for House Wrens ( Troglodytes aedon ), Red-naped Sapsuckers ( Sphyrapicus nuchalis ), Warbling Vircos ( Vireo gilvus ), and Brewer's Blackbirds ( Euphagus cyanocephalus ). Avian species diversity in meadow habitats may be linked to moisture levels during specific times of the year. Diversity increased during the pre-migratory period of the dry year (1994) when compared with that of the breeding season, but was unchanged in the wet year (1995).     

Butterflies of the Toquima Range, Nevada: distribution, natural history, and comparison to the Toiyabe Range

Studies of Great Basin faunas can provide information for landscape-level adaptive management by federal agencies and shed light on potential effects of climate change in continental interior landscapes. To provide such information, we characterized the butterfly fauna of the Toquima Range, a mountain range in the heart of the Great Basin with topography typical of the region. We also compared the butterfly fauna of the Toquima Range to that of the adjacent Toiyabe Range, which is more topographically complex and species rich but less representative of the Great Basin on the whole. We explicitly addressed the effects of area and water availability on butterfly species richness. Butterfly species presence data were compiled for 14 canons and 1 peak in the Toquima Range. Data from 11 canyons that we inventoried systematically were amenable to statistical analysis. Eighty butterfly species (59 residents) have been recorded from the Toquima Range since 1935. By comparison, 99 species have been recorded from the Toiyabe Range. Mean canyon-level butterfly species richness was significantly lower in the Toquima Range than in the Toiyabe Range. This difference cannot be explained by differences in canyon size between mountain ranges. Within the Toquima Range water availability seems to have a dominant effect on butterfly species richness. Between mountain ranges species richness is influenced by interactions among areas, moisture, and topography. These data should assist managers in developing guidelines for conservation planning in the Great Basin.