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Insectivorous Bat (insectivorous + bat)
Selected AbstractsHabitat use, diet and roost selection by the Big Brown Bat (Eptesicus fuscus) in North America: a case for conserving an abundant speciesMAMMAL REVIEW, Issue 3 2002SALVATORE J. AGOSTA ABSTRACT Insectivorous bats are integral components of terrestrial ecosystems. Despite this, a growing number of factors causing world-wide declines in bat populations have been identified. Relatively abundant species are important for bat conservation because of their role in ecosystems and the research opportunities they offer. In addition, species that have been well-studied present unique opportunities to synthesize information and highlight important areas of focus for conservation and research. This paper focuses on a well-studied abundant bat, Eptesicus fuscus. I review the relevant literature on habitat use, diet and roost selection by E. fuscus in North America, and highlight important areas of conservation and research for this species, including the effects of roost disturbance, control of economically important insect pests, exposure to pesticides, long-term monitoring of populations, and the potential consequences of expanding populations. These issues have broad implications for other species and can be used to focus future research and conservation efforts. [source] Influence of climate and reproductive timing on demography of little brown myotis Myotis lucifugusJOURNAL OF ANIMAL ECOLOGY, Issue 1 2010Winifred F. Frick Summary 1. Estimating variation in demographic rates, such as survival and fecundity, is important for testing life-history theory and identifying conservation and management goals. 2. We used 16 years (1993,2008) of mark,recapture data to estimate age-specific survival and breeding probabilities of the little brown myotis Myotis lucifugus LeConte in southern New Hampshire, USA. Using Kendall & Nichols' (1995) full-likelihood approach of the robust design to account for temporary emigration, we tested whether survival and breeding propensity is influenced by regional weather patterns and timing of reproduction. 3. Our results demonstrate that adult female survival of M. lucifugus ranged from 0·63 (95% CL = 0·56, 0·68) to 0·90 (95% CL = 0·77, 0·94), and was highest in wet years with high cumulative summer precipitation. First-year survival [range: 0·23 (95% CL = 0·14, 0·35) to 0·46 (95% CL = 0·34, 0·57)] was considerably lower than adult survival and depended on pup date of birth, such that young born earlier in the summer (c. late May) had a significantly higher probability of surviving their first year than young born later in the summer (c. mid-July). Similarly, the probability of young females returning to the maternity colony to breed in the summer following their birth year was higher for individuals born earlier in the summer [range: 0·23 (95% CL = 0·08, 0·50) to 0·53 (95% CL = 0·30, 0·75)]. 4. The positive influence of early parturition on 1st-year survival and breeding propensity demonstrates significant fitness benefits to reproductive timing in this temperate insectivorous bat. 5. Climatic factors can have important consequences for population dynamics of temperate bats, which may be negatively affected by summer drying patterns associated with global climate change. 6. Understanding long-term demographic trends will be important in the face of a novel disease phenomenon (White-Nose Syndrome) that is associated with massive mortalities in hibernating bat species, including M. lucifugus, in the northeastern United States. [source] The Role of Fruits and Insects in the Nutrition of Frugivorous Bats: Evaluating the Use of Stable Isotope Models,BIOTROPICA, Issue 3 2001L. Gerardo Herrera M. ABSTRACT We estimated the relative contribution of fruits and insects as sources of dietary protein in two species of Neotropical frugivorous bats (Artibeus jamaicensis and Sturnira lilium) using stable carbon and nitrogen isotope analyses. An insectivorous species (Pteronotus parnellii) was also included for comparison. We found constant patterns in stable carbon and nitrogen isotope composition in blood that separated the two species of frugivorous bats from the insectivorous bat. When we used these isotopic values (combined with those of dietary fruits and insects) to estimate the percent contribution of fruits and insects to the diet of the bats, we obtained different results, depending on assumptions and model adopted. We tested models using both 8"N and 8,3C results simultaneously and separately and further used diet-tissue fractionation factors of 3%o for nitrogen and 1 and 3.5%o for carbon. We found that a carbon-based model with a diet-blood enrichment factor of 3.5%o produced the most parsimonious results. The model estimated that A. jamaicensis and S. lilium obtained most of their protein requirements from fruits, whereas P. parnellii fed mostly on insects. No sexual or seasonal variations in the diet of the two frugivorous species were detected. We found no evidence that the diet of sexually active females differed from that of nonsexually active females in the two species of frugivorous bats. We suggest that future studies better define isotopic fractionation between diet and tissues of bats using captive rearing and controlled diets. [source] Acoustic identification of insectivorous bats (order Chiroptera) of Yucatan, MexicoJOURNAL OF ZOOLOGY, Issue 1 2002J. Rydell Abstract The echolocation calls of insectivorous bats of the northern Yucatan Peninsula, Mexico, with the exception of the phyllostomids and molossids, are presented. The aim is to provide a catalogue of bat sounds that can be used for acoustic inventories of insectivorous bats using the Pettersson heterodyne and time-expansion bat detectors. The acoustic method can be used alone or in combination with inventories based on mist-netting, a method more suitable for the low-intensity echolocators (mainly the phyllostomids), which are difficult to monitor acoustically. The insectivorous species of the Yucatan are generally easy to identify by their echolocation calls, particularly when combined with visual observations of foraging bats at dusk. [source] | ||||||||||