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Ecological niche models have become very popular for analysing the potential distribution of species. Nevertheless, models are strongly influenced by many factors, such as spatial resolution, environmental variables and the quality of distribution records. In this paper, we evaluated how ecological niche models changed with the addition of records accumulated over four decades. Our model species was the stripe-headed round-eared bat ( T onatia saurophila). Thus, with data organized in chronological order, we could observe how the models changed in predicting distributions over time in comparison with all known point locations. We tested if partial models could predict the occurrence of new unpublished records for savannah areas in central Brazil, considering that the species is typically associated with forest environments. Our results indicate a high omission rate for models built with point localities from the 1970s and 1980s (58.5% and 50.0% of all known points respectively), and predicted that the species could occur in central Brazil. Although T . saurophila has indeed been recorded recently in central Brazil, it was found in places different from those predicted by the models using these restricted earlier data. Nevertheless, the environmental suitability of such areas is significantly different from sites largely described in earlier records from the Amazonia region, as shown by principal components analysis. We argue that populations of T . saurophila that occupy open habitats in central South America (including Caatinga, Cerrado, Chaco and semi-deciduous interior forests) deserve further study at the genetic level to determine if bats in these very different habitats are taxonomically distinct from Amazonian populations. Our results also suggest that models based on very limited datasets for species occurrence can lead conservationists or decision makers to wrong conclusions. [ABSTRACT FROM AUTHOR]

The probability of persistence of many species of hibernating bats in the United States is greatly reduced by an emerging infectious disease, white-nose syndrome (WNS). In the United States WNS is rapidly spreading and is associated with a psychrophilic fungus, Geomyces destructans. WNS has caused massive mortality of bats that hibernate. Efforts to control the disease have been ineffective. The culling of bats in hibernacula has been proposed as a way to break the transmission cycle or slow the spread of WNS. We formulated a disease model to examine the efficacy of culling to abate WNS in bat populations. We based the model dynamics on disease transmission in maternity roosts, swarms, and hibernacula, which are the arenas of contact among bats. Our simulations indicated culling will not control WNS in bats primarily because contact rates are high among colonial bats, contact occurs in multiple arenas, and periodic movement between arenas occurs. In general, culling is ineffective in the control of animal diseases in the wild. [ABSTRACT FROM AUTHOR]

Townsend's Big-eared Bat (Corynorhinus townsendii) is a species of conservation concern for many states and provinces. However, little is known about key demographic parameters, such as survival, for this species due to its sensitivity to human disturbance. This species can also be vulnerable to injuries from wing bands; the most commonly applied marking technique used in the past to estimate survival in bats. During the US Fish and Wildlife Service's Bat Banding Program (1932-1972), CM Senger banded 1,346 Townsend's Big-eared Bats at 3 major cave systems in Washington during 1964-1975, and continued to recapture banded bats until 1980. I applied current mark-recapture techniques to retrospectively estimate survival of hibernating Townsend's Big-Eared Bats banded by CM Senger. I also investigated sex, time, and trend effects on survival and capture probabilities of these 3 populations of bats using Cormack-Jolly-Seber (CJS) open models and the modeling capabilities of program MARK. For each location, estimates of annual survival and capture probabilities varied somewhat by sex and ranged from 0.54 to 0.68 for males and 0.60 to 0.67 for females. During the banding study, band injuries were noted and populations declined at all locations potentially violating assumptions of the CJS model. However, the dataset from which these estimates were derived is likely to be the most complete and well-maintained dataset in the Bat Banding Program files. Resulting annual survival estimates from these data were relatively precise and modeling provided evidence of time and trend effects and differences in survival between the sexes. These results provide historical, post hoc estimates of an important life-history parameter for this species of bat wintering in caves in 3 localized areas of Washington State. [ABSTRACT FROM AUTHOR]

The article offers information on the mammalian species Leptonycteris yerbabuenae, a lesser long-nosed bat. Leptonycteris yerbabuenae is a leaf-nosed bat with an elongated snout and the skull has an elongate rostrum bearing a small, triangular nose leaf. The northern limit L. yerbabuenae' s distribution extends from the Picacho Mountains in southern Arizona southwest to the Agua Dulce Mountains and southeast to the Chiricahua Mountains, and in southwestern New Mexico in the Animas and Pelonicillo mountains. The large body size of L. yerbabuenae and its high wingd-loading ratio facilitate energetically efficient. Information regarding their fossil record, ontogeny and reproduction, ecology, animal husbandry, behavior, genetics and conservation status are also discussed.

Reports a study which evaluated the nocturnal use of bridges by bats in the Central Oregon Coast Range. Materials and methods; Results; Discussion of the results.

Reports on the results of a study which monitored the activity of Corynorhinus townsendii virginianus bats in five habitats in Kentucky's Daniel Boone National Forest during the months of June, July and August 1992. Use of narrow-band ultrasonic bat detectors; Description of the study area; Bat species found in the area; Comparison of echolocation calls.

Reports on the use of radio telemetry to determine Virginia big-eared bat foraging area size in Kentucky. Use of habitat in Daniel Boone National Forest (DBNF), Kentucky; Attachment of radio transmitters to 30 males in 1990 and 30 females in 1991; Recommendation of protection of foraging habitat to insure long-term survival of Virginia big-eared bats in Kentucky.