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Hohoff TC, Deppe JL. Factors influencing the detection and occupancy of little brown bats ( Myotis lucifugus). Ecol Evol 2024; 14:e10916. [PMID: 38304264 PMCID: PMC10828732 DOI: 10.1002/ece3.10916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Revised: 01/10/2024] [Accepted: 01/19/2024] [Indexed: 02/03/2024] Open
Abstract
Using acoustics to survey for bats has increased as the need for data on increasingly rare species has also increased. We set out to better understand the difference between mist netting and acoustic detection probabilities between these two methods for the little brown bat (Myotis lucifugus), a species highly impacted by white-nose syndrome and currently considered for federal listing in the United States. We also analyzed occupancy relationships with local and landcover variables. We surveyed 15 sites using mist netting paired with an acoustic recorder for multiple nights to estimate detection probability of this species. We also deployed acoustic recorders at another 73 sites. We found that detection rates for mist netting were very low but increased with day of year and decreased from proximity to water. Acoustic surveys had higher detection rates, but there was an approximately 30% likelihood of false-positive detections. At the mean distance to water and day of year, acoustic surveys had a detection rate 55 times higher than mist netting. There were not significant factors influencing occupancy of little brown bats, only a slight positive relationship between forested largest patch, landscape patch richness and forest basal area. Given the declines in little brown bat populations since white-nose syndrome, it is even more critical that we consider the very low detection rate of mist netting compared to acoustic surveys.
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Affiliation(s)
- Tara C. Hohoff
- Department of Biological SciencesEastern Illinois UniversityCharlestonIllinoisUSA
| | - Jill L. Deppe
- Department of Biological SciencesEastern Illinois UniversityCharlestonIllinoisUSA
- Present address:
National Audubon SocietyWashingtonDCUSA
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2
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Crawford RD, O'Keefe JM. Improving the science and practice of using artificial roosts for bats. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2024; 38:e14170. [PMID: 37650433 DOI: 10.1111/cobi.14170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/11/2023] [Accepted: 07/27/2023] [Indexed: 09/01/2023]
Abstract
Worldwide, artificial bat roosts (e.g., bat boxes, bark mimics, bat condos) are routinely deployed for conservation, mitigation, and community engagement. However, scant attention has been paid to developing best practices for the use of artificial roosts as conservation tools. Although bats readily occupy artificial roosts, occupancy and abundance data are misleading indicators of habitat quality. Lacking information on bat behavior, health, and fitness in artificial roosts, their conservation efficacy cannot be adequately validated. We considered the proximal and ultimate factors, such as evolutionarily reliable cues, that may prompt bats to preferentially use and show fidelity to suboptimal artificial roosts even when high-quality alternatives are available. Possible negative health and fitness consequences for artificial roost inhabitants include exposure to unstable and extreme microclimates in poorly designed roosts, and vulnerability to larger numbers of ectoparasites in longer lasting artificial roosts that house larger bat colonies than in natural roosts. Bats using artificial roosts may have lower survival rates if predators have easy access to roosts placed in conspicuous locations. Bats may be lured into occupying low-quality habitats if attractive artificial roosts are deployed on polluted urban and agricultural landscapes. To advance the science behind artificial bat roosts, we present testable research hypotheses and suggestions to improve the quality of artificial roosts for bats and decrease risks to occupants. Because continued loss of natural roosts may increase reliance on alternatives, such as artificial roosts, it is imperative that this conservation practice be improved.
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Affiliation(s)
- Reed D Crawford
- Program in Ecology, Evolution, and Conservation Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
| | - Joy M O'Keefe
- Program in Ecology, Evolution, and Conservation Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
- Department of Natural Resources and Environmental Sciences, University of Illinois at Urbana-Champaign, Urbana, Illinois, USA
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3
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Carlin E, J. Somers M, Scheun J, Campbell R, Ganswindt A. Quantification of faecal glucocorticoid metabolites as a measure of stress in the rock hyrax
Procavia capensis
living in an urban green space. WILDLIFE BIOLOGY 2021. [DOI: 10.1002/wlb3.01011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- E. Carlin
- Mammal Research Inst., Dept of Zoology and Entomology, Univ. of Pretoria Pretoria South Africa
| | - M. J. Somers
- Mammal Research Inst., Dept of Zoology and Entomology, Univ. of Pretoria Pretoria South Africa
- Centre for Invasion Biology, Univ. of Pretoria Pretoria South Africa
| | - J. Scheun
- Mammal Research Inst., Dept of Zoology and Entomology, Univ. of Pretoria Pretoria South Africa
- Dept of Life and Consumer Sciences, Univ. of South Africa Pretoria South Africa
| | - R. Campbell
- National Zoological Garden, South African National Biodiversity Inst. Pretoria South Africa
| | - A. Ganswindt
- Mammal Research Inst., Dept of Zoology and Entomology, Univ. of Pretoria Pretoria South Africa
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4
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Thorne TJ, Matczak E, Donnelly M, Franke MC, Kerr KCR. Occurrence of a forest-dwelling bat, northern myotis ( Myotis septentrionalis), within Canada’s largest conurbation. JOURNAL OF URBAN ECOLOGY 2021. [DOI: 10.1093/jue/juab029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
While some species thrive in urban areas, many are absent from such environments. Those that are successful often have high behavioural flexibility that allows them to exploit new niches in a human-modified landscape. Northern myotis (Myotis septentrionalis) is an endangered bat species rarely identified in urban areas, though it is unclear whether this is due to absence or difficulties in surveying. We investigated the ecology of a population of northern myotis within Canada’s largest conurbation, including reproductive status, roosting preference, and movements. Using capture surveys, we confirmed the presence of reproductive females and healthy juveniles over two seasons. Using radio telemetry and acoustic surveys, we identified a cluster of tree roosts in the centre of the forest, and foraging areas concentrated around waterways within the bounds of the forest. These observations suggest the roosting and movement ecology of this population is similar to that observed for this species in rural environments, despite the urban surroundings. Our results suggest that northern myotis is not a synurbic species but can occur within urbanized environments when suitable habitat is available. We suggest that large forest patches with mature, interior forest cover are likely to be an important resource for northern myotis, and they will be vulnerable to the loss or fragmentation of these features in rapidly urbanizing landscapes. These findings are highly relevant to the ecology and preservation of northern myotis and present a case for greater consideration of this species in urban forests.
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Affiliation(s)
- Toby J Thorne
- Wildlife and Science Division, Toronto Zoo, 361A Old Finch Avenue, Toronto, Ontario M1B 5K7, Canada
| | - Eryk Matczak
- Wildlife and Science Division, Toronto Zoo, 361A Old Finch Avenue, Toronto, Ontario M1B 5K7, Canada
| | - Melissa Donnelly
- Wildlife and Science Division, Toronto Zoo, 361A Old Finch Avenue, Toronto, Ontario M1B 5K7, Canada
| | - Maria C Franke
- Wildlife and Science Division, Toronto Zoo, 361A Old Finch Avenue, Toronto, Ontario M1B 5K7, Canada
| | - Kevin C R Kerr
- Wildlife and Science Division, Toronto Zoo, 361A Old Finch Avenue, Toronto, Ontario M1B 5K7, Canada
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5
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Browning E, Barlow KE, Burns F, Hawkins C, Boughey K. Drivers of European bat population change: a review reveals evidence gaps. Mamm Rev 2021. [DOI: 10.1111/mam.12239] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Affiliation(s)
- Ella Browning
- Centre for Biodiversity and Ecology Research Department of Genetics, Evolution and Environment Division of Biosciences University College London LondonWC1E 6BTUK
- Institute of Zoology Zoological Society of London Regents Park LondonNW1 4RYUK
| | - Kate E. Barlow
- The Bat Conservation Trust Quadrant House, 250 Kennington Lane LondonSE11 5RDUK
| | - Fiona Burns
- The Royal Society for the Protection of Birds Centre for Conservation Science SandySG19 2DLUK
| | - Charlotte Hawkins
- The Bat Conservation Trust Quadrant House, 250 Kennington Lane LondonSE11 5RDUK
| | - Katherine Boughey
- The Bat Conservation Trust Quadrant House, 250 Kennington Lane LondonSE11 5RDUK
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Patriquin KJ, Guy C, Hinds J, Ratcliffe JM. Male and female bats differ in their use of a large urban park. JOURNAL OF URBAN ECOLOGY 2019. [DOI: 10.1093/jue/juz015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Understanding how wildlife respond to ever-encroaching urbanization is of great concern. Bats are the second-most speciose mammalian order and while many appear to be urban adapted, we currently have a limited understanding of their demography and habitat use within urban environments. Using a combination of captures to obtain demographic data, radio-telemetry to examine foraging and roosting behaviour, and data on diet and prey availability, we examined how big brown bats (Eptesicus fuscus), a synurbic species, use an urban green space (High Park) in Canada’s largest city centre, Toronto. We found that adult males outnumbered adult females more than two to one and that males were found throughout the park, while females were concentrated in an area with greater access to water, but lower prey availability. We also found that bats of both sexes were in poorer body condition than reported for other non-urban areas, including a site within southern Ontario. Our data suggest that High Park may not provide adequate resources for reproductive females as they were never found roosting in the park and beetles, their preferred prey, were limited. Although previous studies suggest urban green spaces may offer refuge to bats, most have not considered sex-specific responses to urbanization as they have largely been based on acoustic surveys. Our study therefore highlights the importance of considering demographic differences in response to urbanization to better inform urban management plans and green space development.
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Affiliation(s)
- Krista J Patriquin
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, William G Davis Building, Mississauga, Ontario L5L 1C6, Canada
| | - Cylita Guy
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, William G Davis Building, Mississauga, Ontario L5L 1C6, Canada
| | - Joshua Hinds
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, William G Davis Building, Mississauga, Ontario L5L 1C6, Canada
| | - John M Ratcliffe
- Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, William G Davis Building, Mississauga, Ontario L5L 1C6, Canada
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Samuelson AE, Gill RJ, Brown MJF, Leadbeater E. Lower bumblebee colony reproductive success in agricultural compared with urban environments. Proc Biol Sci 2018; 285:20180807. [PMID: 30051852 PMCID: PMC6030522 DOI: 10.1098/rspb.2018.0807] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2018] [Accepted: 05/31/2018] [Indexed: 11/26/2022] Open
Abstract
Urbanization represents a rapidly growing driver of land-use change. While it is clear that urbanization impacts species abundance and diversity, direct effects of urban land use on animal reproductive success are rarely documented. Here, we show that urban land use is linked to long-term colony reproductive output in a key pollinator. We reared colonies from wild-caught bumblebee (Bombus terrestris) queens, placed them at sites characterized by varying degrees of urbanization from inner city to rural farmland and monitored the production of sexual offspring across the entire colony cycle. Our land-use cluster analysis identified three site categories, and this categorization was a strong predictor of colony performance. Crucially, colonies in the two clusters characterized by urban development produced more sexual offspring than those in the cluster dominated by agricultural land. These colonies also reached higher peak size, had more food stores, encountered fewer parasite invasions and survived for longer. Our results show a link between urbanization and bumblebee colony reproductive success, supporting the theory that urban areas provide a refuge for pollinator populations in an otherwise barren agricultural landscape.
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Affiliation(s)
- Ash E Samuelson
- School of Biological Sciences, Royal Holloway University of London, Egham, UK
| | - Richard J Gill
- Department of Life Sciences, Imperial College London, Silwood Park Campus, Ascot, UK
| | - Mark J F Brown
- School of Biological Sciences, Royal Holloway University of London, Egham, UK
| | - Ellouise Leadbeater
- School of Biological Sciences, Royal Holloway University of London, Egham, UK
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9
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Pauli BP, Zollner PA, Haulton GS. Nocturnal habitat selection of bats using occupancy models. J Wildl Manage 2017. [DOI: 10.1002/jwmg.21251] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Benjamin P. Pauli
- Department of Forestry and Natural Resources; Purdue University; 195 Marsteller Street West Lafayette IN 47907 USA
| | - Patrick A. Zollner
- Department of Forestry and Natural Resources; Purdue University; 195 Marsteller Street West Lafayette IN 47907 USA
| | - G. Scott Haulton
- Division of Forestry; Indiana Department of Natural Resources; 402 West Washington Street Indianapolis IN 46204 USA
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10
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Uhrin M, Benda P, Kaňuch P. Different responses of attic-dwelling bat species to landscape naturalness. Mamm Biol 2017. [DOI: 10.1016/j.mambio.2016.10.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Krauel JJ, LeBuhn G. Patterns of Bat Distribution and Foraging Activity in a Highly Urbanized Temperate Environment. PLoS One 2016; 11:e0168927. [PMID: 28030640 PMCID: PMC5193347 DOI: 10.1371/journal.pone.0168927] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2016] [Accepted: 12/08/2016] [Indexed: 11/28/2022] Open
Abstract
Understanding how to manage biodiversity in urban areas will become increasingly important as density of humans residing in urban centers increases and urban areas expand. While considerable research has documented the shifts in biodiversity along urbanization gradients, much less work has focused on how characteristics of dense urban centers, effectively novel environments, influence behavior and biodiversity. Urban bats in San Francisco provide an opportunity to document changes in behavior and biodiversity to very high-density development. We studied (1) the distribution and abundance of bat foraging activity in natural areas; and (2) characteristics of natural areas that influence the observed patterns of distribution and foraging activity. We conducted acoustic surveys of twenty-two parks during 2008-2009. We confirmed the presence of four species of bats (Tadarida brasiliensis, Myotis yumanensis, Lasiurus blossevillii, and M. lucifugus). T. brasiliensis were found in all parks, while M. yumanensis occurred in 36% of parks. Results indicate that proximity to water, park size, and amount of forest edge best explained overall foraging activity. Proximity to water best explained species richness. M. yumanensis activity was best explained by reduced proportion of native vegetation as well as proximity to water. Activity was year round but diminished in December. We show that although bats are present even in very densely populated urban centers, there is a large reduction in species richness compared to that of outlying areas, and that most habitat factors explaining their community composition and activity patterns are similar to those documented in less urbanized environments.
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Affiliation(s)
- Jennifer J. Krauel
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
| | - Gretchen LeBuhn
- Department of Biology, San Francisco State University, San Francisco, California, United States of America
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Voigt CC, Kingston T. Bats and Buildings: The Conservation of Synanthropic Bats. BATS IN THE ANTHROPOCENE: CONSERVATION OF BATS IN A CHANGING WORLD 2015. [PMCID: PMC7123121 DOI: 10.1007/978-3-319-25220-9_14] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Humans have shared buildings with bats for thousands of years, probably as early as first humans built primitive huts. Indeed, many bat species can be defined as synanthropic, i.e., they have a strong ecological association with humans. Bats have been observed using buildings as roosting and foraging sites, temporary shelters, for reproduction and hibernation. A synanthropic lifestyle may result in direct fitness benefits owing to energetic advantages in warmer roosts, which may ultimately lead to more rapid gestation and faster development of juveniles, or by being less exposed to natural predators in urban environments. All these benefits may allow bats to use buildings as stepping stones to exploit habitats otherwise devoid of roosting structures and may even lead to the expansion of geographic ranges. Yet, the coexistence with humans also comes with some risks. Bats may be exposed to chemical pollutants, particularly preservation chemicals used on lumber or during pest control measures. Bats may also be at risk of direct persecution or they may die accidently if trapped within buildings. In general, eviction of bats from buildings should follow the general rule of avoidance–mitigation–compensation. When considering conservation measures for synanthropic bats, it is most important to assess the role of the building for different life stages of bats. Construction work at buildings should be conducted in a manner that minimizes disturbance of bats. Artificial roosts can replace lost roosts, yet bats will often not accept alternative roosts. Demographic changes in human populations may lead to the abandonment of buildings, for example, in rural areas and to increased conflicts in urban areas when old buildings are replaced by new buildings or when previously unoccupied space in buildings is renovated. We advocate maintenance and enhancement of roosts for synanthropic bats, in addition to outreach and education campaigns, to improve the tolerance of humans for synanthropic bats.
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Rollinson DP, Coleman JC, Downs CT. Roost temperature and fidelity of Wahlberg’s epauletted fruit bat,Epomophorus wahlbergi, in an urban environment. AFRICAN ZOOLOGY 2015. [DOI: 10.1080/15627020.2014.11407633] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Ancillotto L, Tomassini A, Russo D. The fancy city life: Kuhl's pipistrelle, Pipistrellus kuhlii, benefits from urbanisation. WILDLIFE RESEARCH 2015. [DOI: 10.1071/wr15003] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Context
Urbanisation is often regarded as a major threat to global biodiversity. Although wildlife is frequently affected by urbanisation, some species may actually benefit from it. Bats are among the commonest wild mammals in human-modified areas, and some species seem particularly well suited to exploit urban habitats where they find roosting and foraging opportunities.
Aims
We investigated habitat selection around roosts of synurbic Kuhl’s pipistrelles, Pipistrellus kuhlii, in Italy.
Methods
We measured the effects of the amount of urban habitat on bat reproductive timing and success in human-modified environments.
Key results
We found that P. kuhlii selects roosts surrounded by areas featuring urban habitats, especially those subject to urban development. Colonies in cities and suburbs advanced parturition time and produced more pups than those in rural areas. Permanent water sources and artificial lights in the surrounding habitats also seemed to favour the species reproductive success, particularly in developing urban areas.
Conclusions
Our results showed that this bat benefits from urbanisation and provided new insights on the effects of this major process on animal ecology and conservation in urban environments.
Implications
Although the ecological flexibility and positive response to urbanisation of P. kuhlii may help explain its recent range expansion, the role of climate change as a potential driver of this process has yet to be tested.
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Rollinson DP, Coleman JC, Downs CT. Roost Temperature and Fidelity of Wahlberg's Epauletted Fruit Bat,Epomophorus wahlbergi, in an Urban Environment. AFRICAN ZOOLOGY 2014. [DOI: 10.3377/004.049.0218] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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16
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Tree cavity availability across forest, park, and residential habitats in a highly urban area. Urban Ecosyst 2014. [DOI: 10.1007/s11252-014-0383-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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17
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Can pinewoods provide habitat for a deciduous forest specialist? A two-scale approach to the habitat selection of Bechstein's bat. Mamm Biol 2014. [DOI: 10.1016/j.mambio.2013.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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18
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Fenton MB. A perspective on bats (Chiroptera). KOEDOE: AFRICAN PROTECTED AREA CONSERVATION AND SCIENCE 2013. [DOI: 10.4102/koedoe.v55i1.1140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Abstract
With over 130 species, bats are the most diverse group of mammals almost everywhere in sub-Saharan Africa. Since 2000, two books (Monadjem et al. 2010; Taylor 2000) have made it much easier to appreciate this reality. Species previously unrecognised are frequent discoveries (e.g. Taylor et al. 2012). Whilst most species are mainly insectivorous, some rely more directly on plants, taking fruit and visiting flowers to obtain nectar and pollen. The combination of mobility, long lifespan and diversity of trophic roles makes bats potentially valuable as indicators of ecosystem health (Cumming & Spiesman 2006). Lack of detailed information, however, makes it easy to overlook bats when focusing on issues of conservation.
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Patterns of Acoustical Activity of Bats Prior to and Following White-Nose Syndrome Occurrence. JOURNAL OF FISH AND WILDLIFE MANAGEMENT 2011. [DOI: 10.3996/042011-jfwm-027] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
White-nose Syndrome (WNS), a wildlife health concern that has decimated cave-hibernating bat populations in eastern North America since 2006, began affecting source-caves for summer bat populations at Fort Drum, a U.S. Army installation in New York in the winter of 2007–2008. As regional die-offs of bats became evident, and Fort Drum's known populations began showing declines, we examined whether WNS-induced change in abundance patterns and seasonal timing of bat activity could be quantified using acoustical surveys, 2003–2010, at structurally uncluttered riparian–water habitats (i.e., streams, ponds, and wet meadows). As predicted, we observed significant declines in overall summer activity between pre-WNS and post-WNS years for little brown bats Myotis lucifugus, northern bats M. septentrionalis, and Indiana bats M. sodalis. We did not observe any significant change in activity patterns between pre-WNS and post-WNS years for big brown bats Eptesicus fuscus, eastern red bats Lasiurus borealis, or the small number of tri-colored bats Perimyotis subflavus. Activity of silver-haired bats Lasionycteris noctivagans increased from pre-WNS to post-WNS years. Activity levels of hoary bats Lasiurus cinereus significantly declined between pre- and post-WNS years. As a nonhibernating, migratory species, hoary bat declines might be correlated with wind-energy development impacts occurring in the same time frame rather than WNS. Intraseason activity patterns also were affected by WNS, though the results were highly variable among species. Little brown bats showed an overall increase in activity from early to late summer pre-WNS, presumably due to detections of newly volant young added to the local population. However, the opposite occurred post-WNS, indicating that reproduction among surviving little brown bats may be declining. Our data suggest that acoustical monitoring during the summer season can provide insights into species' relative abundance on the landscape as affected by the occurrence of WNS.
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