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Whiting JC, Doering B, Aho K, Bybee BF. Disturbance of hibernating bats due to researchers entering caves to conduct hibernacula surveys. Sci Rep 2024; 14:13496. [PMID: 38866865 PMCID: PMC11169401 DOI: 10.1038/s41598-024-64172-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 06/05/2024] [Indexed: 06/14/2024] Open
Abstract
Estimating population changes of bats is important for their conservation. Population estimates of hibernating bats are often calculated by researchers entering hibernacula to count bats; however, the disturbance caused by these surveys can cause bats to arouse unnaturally, fly, and lose body mass. We conducted 17 hibernacula surveys in 9 caves from 2013 to 2018 and used acoustic detectors to document cave-exiting bats the night following our surveys. We predicted that cave-exiting flights (i.e., bats flying out and then back into caves) of Townsend's big-eared bats (Corynorhinus townsendii) and western small-footed myotis (Myotis ciliolabrum) would be higher the night following hibernacula surveys than on nights following no surveys. Those two species, however, did not fly out of caves more than predicted the night following 82% of surveys. Nonetheless, the activity of bats flying out of caves following surveys was related to a disturbance factor (i.e., number of researchers × total time in a cave). We produced a parsimonious model for predicting the probability of Townsend's big-eared bats flying out of caves as a function of disturbance factor and ambient temperature. That model can be used to help biologists plan for the number of researchers, and the length of time those individuals are in a cave to minimize disturbing bats.
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Affiliation(s)
- Jericho C Whiting
- Department of Biology, Brigham Young University-Idaho, Rexburg, ID, USA.
| | | | - Ken Aho
- Department of Biological Sciences, Idaho State University, Pocatello, ID, USA
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2
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Whiting-Fawcett F, Blomberg AS, Troitsky T, Meierhofer MB, Field KA, Puechmaille SJ, Lilley TM. A Palearctic view of a bat fungal disease. CONSERVATION BIOLOGY : THE JOURNAL OF THE SOCIETY FOR CONSERVATION BIOLOGY 2024:e14265. [PMID: 38616727 DOI: 10.1111/cobi.14265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 01/02/2024] [Accepted: 01/20/2024] [Indexed: 04/16/2024]
Abstract
The fungal infection causing white-nose disease in hibernating bats in North America has resulted in dramatic population declines of affected species, since the introduction of the causative agent Pseudogymnoascus destructans. The fungus is native to the Palearctic, where it also infects several bat species, yet rarely causes severe pathology or the death of the host. Pseudogymnoascus destructans infects bats during hibernation by invading and digesting the skin tissue, resulting in the disruption of torpor patterns and consequent emaciation. Relations among pathogen, host, and environment are complex, and individuals, populations, and species respond to the fungal pathogen in different ways. For example, the Nearctic Myotis lucifugus responds to infection by mounting a robust immune response, leading to immunopathology often contributing to mortality. In contrast, the Palearctic M. myotis shows no significant immunological response to infection. This lack of a strong response, resulting from the long coevolution between the hosts and the pathogen in the pathogen's native range, likely contributes to survival in tolerant species. After more than 15 years since the initial introduction of the fungus to North America, some of the affected populations are showing signs of recovery, suggesting that the fungus, hosts, or both are undergoing processes that may eventually lead to coexistence. The suggested or implemented management methods of the disease in North America have encompassed, for example, the use of probiotics and fungicides, vaccinations, and modifying the environmental conditions of the hibernation sites to limit the growth of the pathogen, intensity of infection, or the hosts' responses to it. Based on current knowledge from Eurasia, policy makers and conservation managers should refrain from disrupting the ongoing evolutionary processes and adopt a holistic approach to managing the epizootic.
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Affiliation(s)
- F Whiting-Fawcett
- Department of Evolution, Ecology and Behaviour, University of Liverpool, Liverpool, UK
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - A S Blomberg
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - T Troitsky
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - M B Meierhofer
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
| | - K A Field
- Department of Biology, Bucknell University, Lewisburg, Pennsylvania, USA
| | - S J Puechmaille
- Institut des Sciences de l'Évolution Montpellier (ISEM), University of Montpellier, CNRS, EPHE, IRD, Montpellier, France
- Institut Universitaire de France, Paris, France
| | - T M Lilley
- BatLab Finland, Finnish Museum of Natural History, University of Helsinki, Helsinki, Finland
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3
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Klüg-Baerwald BJ, Lausen CL, Burns SM, Brigham RM. Physiological and behavioural adaptations by big brown bats hibernating in dry rock crevices. J Comp Physiol B 2024; 194:203-212. [PMID: 38587619 DOI: 10.1007/s00360-024-01546-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 01/31/2024] [Accepted: 02/29/2024] [Indexed: 04/09/2024]
Abstract
Winter energy stores are finite and factors influencing patterns of activity are important for overwintering energetics and survival. Hibernation patterns (e.g., torpor bout duration and arousal frequency) often depend on microclimate, with more stable hibernacula associated with greater energy savings than less stable hibernacula. We monitored hibernation patterns of individual big brown bats (Eptesicus fuscus; Palisot de Beauvois, 1796) overwintering in rock-crevices that are smaller, drier, and less thermally stable than most known cave hibernacula. While such conditions would be predicted to increase arousal frequency in many hibernators, we did not find support for this. We found that bats were insensitive to changes in hibernacula microclimate (temperature and humidity) while torpid. We also found that the probability of arousal from torpor remained under circadian influence, likely because throughout the winter during arousals, bats commonly exit their hibernacula. We calculated that individuals spend most of their energy on maintaining a torpid body temperature a few degrees above the range of ambient temperatures during steady-state torpor, rather than during arousals as is typical of other small mammalian hibernators. Flight appears to be an important winter activity that may expedite the benefits of euthermic periods and allow for short, physiologically effective arousals. Overall, we found that big brown bats in rock crevices exhibit different hibernation patterns than conspecifics hibernating in buildings and caves.
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Affiliation(s)
- B J Klüg-Baerwald
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK, S4S 0A2, Canada
| | - C L Lausen
- Wildlife Conservation Society Canada, PO Box 606, Kaslo, BC, V0G 1M0, Canada
| | - S M Burns
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK, S4S 0A2, Canada
| | - R M Brigham
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK, S4S 0A2, Canada.
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Blejwas K, Beard L, Buchanan J, Lausen CL, Neubaum D, Tobin A, Weller TJ. COULD WHITE-NOSE SYNDROME MANIFEST DIFFERENTLY IN MYOTIS LUCIFUGUS IN WESTERN VERSUS EASTERN REGIONS OF NORTH AMERICA? A REVIEW OF FACTORS. J Wildl Dis 2023; 59:381-397. [PMID: 37270186 DOI: 10.7589/jwd-d-22-00050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2022] [Accepted: 02/28/2023] [Indexed: 06/05/2023]
Abstract
White-nose syndrome (WNS) has notably affected the abundance of Myotis lucifugus (little brown myotis) in North America. Thus far, substantial mortality has been restricted to the eastern part of the continent where the cause of WNS, the invasive fungus Pseudogymnoascus destructans, has infected bats since 2006. To date, the state of Washington is the only area in the Western US or Canada (the Rocky Mountains and further west in North America) with confirmed cases of WNS in bats, and there the disease has spread more slowly than it did in Eastern North America. Here, we review differences between M. lucifugus in western and eastern parts of the continent that may affect transmission, spread, and severity of WNS in the West and highlight important gaps in knowledge. We explore the hypothesis that western M. lucifugus may respond differently to WNS on the basis of different hibernation strategies, habitat use, and greater genetic structure. To document the effect of WNS on M. lucifugus in the West most effectively, we recommend focusing on maternity roosts for strategic disease surveillance and monitoring abundance. We further recommend continuing the challenging work of identifying hibernation and swarming sites to better understand the microclimates, microbial communities, and role in disease transmission of these sites, as well as the ecology and hibernation physiology of bats in noncavernous hibernacula.
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Affiliation(s)
- Karen Blejwas
- Alaska Department of Fish and Game, PO Box 110024, Juneau, Alaska 99811, USA
- Except for the first author, all others are listed in alphabetical order
| | - Laura Beard
- Wyoming Game and Fish Department, 260 Buena Vista, Lander, Wyoming 82520, USA
| | - Joseph Buchanan
- Washington Department of Fish and Wildlife, PO Box 43200, Olympia, Washington 98501, USA
| | - Cori L Lausen
- Wildlife Conservation Society Canada, 202 B Avenue, Kaslo, British Columbia V0G 1M0, Canada
| | - Daniel Neubaum
- Colorado Parks and Wildlife, 711 Independent Ave., Grand Junction, Colorado 81507, USA
| | - Abigail Tobin
- Washington Department of Fish and Wildlife, PO Box 43200, Olympia, Washington 98501, USA
| | - Theodore J Weller
- USDA Forest Service, Pacific Southwest Research Station, 1700 Bayview Drive, Arcata, California 95521, USA
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Mas M, Flaquer C, Puig-Montserrat X, Porres X, Rebelo H, López-Baucells A. Winter bat activity: The role of wetlands as food and drinking reservoirs under climate change. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 828:154403. [PMID: 35276147 DOI: 10.1016/j.scitotenv.2022.154403] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Revised: 03/03/2022] [Accepted: 03/04/2022] [Indexed: 06/14/2023]
Abstract
Bat arousals during hibernation are related to rises in environmental temperature, body water loss and increasing body heat. Therefore, bats either hibernate in cold places or migrate to areas with mild winters to find water and insects to intake. During winter, insects are relatively abundant in wetlands with mild climates when low temperatures hamper insect activity in other places. However, the role of wetlands to sustain winter bat activity has never been fully assessed. To further understand bat behaviour during hibernation, we evaluated how the weather influenced hibernating bats, assessed the temperature threshold that increased bat arousals, and discussed how winter temperatures could affect bat activity under future climate change scenarios. The effects of weather and landscape composition on winter bat activity were assessed by acoustically sampling four different habitats (wetlands, rice paddies, urban areas and salt marshes) in the Ebro Delta (Spain). Our results show one of the highest winter bat foraging activities ever reported, with significantly higher activity in wetlands and urban areas. Most importantly, we found a substantial increase in bat activity triggered when nocturnal temperatures reached ca. 11 °C. By contrasting historical weather datasets, we show that, since the 1940s, there has been an increase by ca. 1.5 °C in winter maximum temperatures and a 180% increase in the number of nights with mean temperatures above 11 °C in the Ebro Delta. Temperature trends suggest that in 60-80 years, winter months will reach average temperatures of 11 °C (except maybe in January), which suggest a potential coming interruption or disappearance of bat hibernation in coastal Mediterranean habitats. This study highlights the significant role of wetlands in bat conservation under a climate change scenario as these humid areas represent one of the few remaining winter foraging habitats.
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Affiliation(s)
- Maria Mas
- BiBio (Biodiversity and Bioindicators Research Group), Natural Sciences Museum of Granollers, Av. Francesc Macia, 51, 08402 Granollers, Catalonia, Spain; CREAF, Universitat Autònoma de Barcelona, Cerdanyola del Valles, 08193, Catalonia, Spain.
| | - Carles Flaquer
- BiBio (Biodiversity and Bioindicators Research Group), Natural Sciences Museum of Granollers, Av. Francesc Macia, 51, 08402 Granollers, Catalonia, Spain
| | - Xavier Puig-Montserrat
- BiBio (Biodiversity and Bioindicators Research Group), Natural Sciences Museum of Granollers, Av. Francesc Macia, 51, 08402 Granollers, Catalonia, Spain; Galanthus Association, Celrà 17460, Catalonia, Spain
| | - Xavier Porres
- Ebro Delta Natural Park, Generalitat de Catalunya, Deltebre, 43580, Catalonia, Spain
| | - Hugo Rebelo
- CIBIO-InBIO, Campus de Vairão, Universidade do Porto, 4485-661 Vairão, Portugal; CIBIO-InBIO, Instituto Superior de Agronomia, Universidade de Lisboa, 1349-017 Lisboa, Portugal; BIOPOLIS Program in Genomics, Biodiversity and Land Planning, CIBIO, Campus de Vairão, 4485-661 Vairão, Portugal
| | - Adrià López-Baucells
- BiBio (Biodiversity and Bioindicators Research Group), Natural Sciences Museum of Granollers, Av. Francesc Macia, 51, 08402 Granollers, Catalonia, Spain
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Rummel AD, Swartz SM, Marsh RL, Faure PA. A comparison of thermal sensitivities of wing muscle contractile properties from a temperate and tropical bat species. J Exp Biol 2022; 225:jeb243987. [PMID: 35546297 PMCID: PMC9234497 DOI: 10.1242/jeb.243987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2022] [Accepted: 05/09/2022] [Indexed: 11/20/2022]
Abstract
Endotherms experience temperature variation among body regions, or regional heterothermy, despite maintaining high core body temperatures. Bat forelimbs are elongated to function as wings, which makes them vulnerable to heat loss and exaggerates regional heterothermy. A tropical bat species, Carollia perspicillata, flies with distal wing muscles that are substantially (>10°C) cooler than proximal wing muscles and significantly less temperature sensitive. We hypothesized that the difference between proximal and distal wing muscles would be even more extreme in a temperate bat species that is capable of flight at variable environmental temperatures. We measured the contractile properties of the proximal pectoralis muscle and distal extensor carpi radialis muscle at a range of temperatures in the big brown bat, Eptesicus fuscus, and compared their thermal dependence with that of the same muscles in C. perspicillata. We found that, overall, temperature sensitivities between species were remarkably similar. The sole exception was the shortening velocity of the pectoralis muscle in E. fuscus, which was less temperature sensitive than in C. perspicillata. This decreased temperature sensitivity in a proximal muscle runs counter to our prediction. We suggest that the relative lability of body temperature in E. fuscus may make better pectoralis function at low temperatures advantageous.
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Affiliation(s)
- Andrea D. Rummel
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02906, USA
| | - Sharon M. Swartz
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02906, USA
- School of Engineering, Brown University, Providence, RI 02906, USA
| | - Richard L. Marsh
- Department of Ecology and Evolutionary Biology, Brown University, Providence, RI 02906, USA
| | - Paul A. Faure
- Department of Psychology, Neuroscience & Behavior, McMaster University, Hamilton, ON L8S 4K1, Canada
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Habitat Associations of Overwintering Bats in Managed Pine Forest Landscapes. FORESTS 2022. [DOI: 10.3390/f13050803] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Research Highlights: Seasonal variation in environmental conditions coinciding with reproductive and energetic demands might result in seasonal differences in species-specific habitat use. We studied a winter assemblage of insectivorous bats and found that species acted as habitat generalists during winter compared to expectations based on the summer active season. Background and Objectives: In temperate regions, seasonal fluctuations in resource availability might restructure local bat assemblages. Initially perceived to only hibernate or migrate to avoid adverse winter conditions, temperate insectivorous bats appear to also employ intermediate overwintering strategies, as a growing body of literature suggests that winter activity is quite prevalent and even common in some lower latitude areas. However, to date, most studies have exclusively assessed habitat associations during summer. Because habitat use during summer is strongly influenced by reproduction, we hypothesized that habitat associations might differ during the non-reproductive winter period. We used acoustic monitoring to assess the habitat associations of bats across a managed pine landscape in the southeastern United States. Materials and Methods: During the winters of 2018 and 2019, we deployed acoustic detectors at 72 unique locations to monitor bat activity and characterized vegetation conditions at two scales (microhabitat and landscape). We used linear mixed models to characterize species-specific activity patterns associated with different vegetation conditions. Results: We found little evidence of different activity patterns during winter. The activity of three species (hoary bat: Lasiurus cinereus; southeastern myotis: Myotis austroriparius; and tricolored bat: Perimyotis subflavus) was not related to vegetation variables and only modest relationships were evident for four other species/groups (big brown bat: Eptesicus fuscus; eastern red bat: L. borealis; Seminole bat: L. seminolus; evening bat: Nycticeius humeralis; and Brazilian free-tailed bat: Tadarida brasiliensis). Conclusions: During winter, the bats in our study were active across the landscape in various cover types, suggesting that they do not exhibit the same habitat associations as in summer. Therefore, seasonal differences in distributions and habitat associations of bat populations need to be considered so that effective management strategies can be devised that help conserve bats year round.
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8
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Klüg-Baerwald BJ, Lausen CL, Wissel B, Brigham RM. Meet You at the Local Watering Hole? No Use of an Artificial Water Resource, and Evidence of Dehydration in Hibernating Bats in the Prairies. ACTA CHIROPTEROLOGICA 2022. [DOI: 10.3161/15081109acc2021.23.2.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
| | - Cori L. Lausen
- Wildlife Conservation Society of Canada, PO Box 606, Kaslo, BC V0G 1M0 Canada
| | - Bjoern Wissel
- Department of Biology, University of Regina, Regina, SK S4S 0A2 Canada
| | - R. Mark Brigham
- Department of Biology, University of Regina, Regina, SK S4S 0A2 Canada
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McGuire LP, Fuller NW, Dzal YA, Haase CG, Klüg-Baerwald BJ, Silas KA, Plowright RK, Lausen CL, Willis CKR, Olson SH. Interspecific variation in evaporative water loss and temperature response, but not metabolic rate, among hibernating bats. Sci Rep 2021; 11:20759. [PMID: 34675252 PMCID: PMC8531132 DOI: 10.1038/s41598-021-00266-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 10/08/2021] [Indexed: 11/30/2022] Open
Abstract
Hibernation is widespread among mammals in a variety of environmental contexts. However, few experimental studies consider interspecific comparisons, which may provide insight into general patterns of hibernation strategies. We studied 13 species of free-living bats, including populations spread over thousands of kilometers and diverse habitats. We measured torpid metabolic rate (TMR) and evaporative water loss (two key parameters for understanding hibernation energetics) across a range of temperatures. There was no difference in minimum TMR among species (i.e., all species achieved similarly low torpid metabolic rate) but the temperature associated with minimum TMR varied among species. The minimum defended temperature (temperature below which TMR increased) varied from 8 °C to < 2 °C among species. Conversely, evaporative water loss varied among species, with species clustered in two groups representing high and low evaporative water loss. Notably, species that have suffered population declines due to white-nose syndrome fall in the high evaporative water loss group and less affected species in the low evaporative water loss group. Documenting general patterns of physiological diversity, and associated ecological implications, contributes to broader understanding of biodiversity, and may help predict which species are at greater risk of environmental and anthropogenic stressors.
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Affiliation(s)
- Liam P McGuire
- Department of Biology, University of Waterloo, 200 University Ave W, Waterloo, ON, N2L 3G1, Canada.
- Department of Biological Sciences, Texas Tech University, 2901 Main St, Lubbock, TX, 79409, USA.
| | - Nathan W Fuller
- Department of Biological Sciences, Texas Tech University, 2901 Main St, Lubbock, TX, 79409, USA
- Nongame and Rare Species Program, Texas Parks and Wildlife, Austin, TX, 78744, USA
| | - Yvonne A Dzal
- Department of Biology, University of Winnipeg, 515 Portage Ave, Winnipeg, MB, R3B 2E9, Canada
| | - Catherine G Haase
- Department of Microbiology and Immunology, Montana State University, PO Box 173520, Bozeman, MT, 59717, USA
- Department of Biology, Austin Peay State University, PO Box 4718, Clarkesville, TN, 37044, USA
| | - Brandon J Klüg-Baerwald
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK, S4S 0A2, Canada
| | - Kirk A Silas
- Wildlife Conservation Society, Health Program, 2300 Southern Blvd, Bronx, NY, 10460, USA
| | - Raina K Plowright
- Department of Microbiology and Immunology, Montana State University, PO Box 173520, Bozeman, MT, 59717, USA
| | - Cori L Lausen
- Wildlife Conservation Society Canada, Bat Program, PO Box 606, Kaslo, BC, V0G 1M0, Canada
| | - Craig K R Willis
- Department of Biology, University of Winnipeg, 515 Portage Ave, Winnipeg, MB, R3B 2E9, Canada
| | - Sarah H Olson
- Wildlife Conservation Society, Health Program, 2300 Southern Blvd, Bronx, NY, 10460, USA
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Hranac CR, Haase CG, Fuller NW, McClure ML, Marshall JC, Lausen CL, McGuire LP, Olson SH, Hayman DTS. What is winter? Modeling spatial variation in bat host traits and hibernation and their implications for overwintering energetics. Ecol Evol 2021; 11:11604-11614. [PMID: 34522327 PMCID: PMC8427580 DOI: 10.1002/ece3.7641] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/31/2021] [Accepted: 04/09/2021] [Indexed: 01/05/2023] Open
Abstract
White-nose syndrome (WNS) has decimated hibernating bat populations across eastern and central North America for over a decade. Disease severity is driven by the interaction between bat characteristics, the cold-loving fungal agent, and the hibernation environment. While we further improve hibernation energetics models, we have yet to examine how spatial heterogeneity in host traits is linked to survival in this disease system. Here, we develop predictive spatial models of body mass for the little brown myotis (Myotis lucifugus) and reassess previous definitions of the duration of hibernation of this species. Using data from published literature, public databases, local experts, and our own fieldwork, we fit a series of generalized linear models with hypothesized abiotic drivers to create distribution-wide predictions of prehibernation body fat and hibernation duration. Our results provide improved estimations of hibernation duration and identify a scaling relationship between body mass and body fat; this relationship allows for the first continuous estimates of prehibernation body mass and fat across the species' distribution. We used these results to inform a hibernation energetic model to create spatially varying fat use estimates for M. lucifugus. These results predict WNS mortality of M. lucifugus populations in western North America may be comparable to the substantial die-off observed in eastern and central populations.
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Affiliation(s)
- C. Reed Hranac
- Molecular Epidemiology and Public Health LaboratoryHopkirk Research InstituteMassey UniversityPalmerston NorthNew Zealand
| | - Catherine G. Haase
- Department of Microbiology and ImmunologyMontana State UniversityBozemanMTUSA
- Present address:
Department of BiologyAustin Peay State UniversityClarksvilleTNUSA
| | - Nathan W. Fuller
- Department of Biological SciencesTexas Tech UniversityLubbockTXUSA
- Present address:
Texas Parks and Wildlife DepartmentNongame and Rare Species ProgramAustinTXUSA
| | | | | | | | - Liam P. McGuire
- Department of Biological SciencesTexas Tech UniversityLubbockTXUSA
- Present address:
Department of BiologyUniversity of WaterlooWaterlooONCanada
| | | | - David T. S. Hayman
- Molecular Epidemiology and Public Health LaboratoryHopkirk Research InstituteMassey UniversityPalmerston NorthNew Zealand
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11
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Blejwas KM, Pendleton GW, Kohan ML, Beard LO. The Milieu Souterrain Superficiel as hibernation habitat for bats: implications for white-nose syndrome. J Mammal 2021; 102:1110-1127. [PMID: 34393669 PMCID: PMC8357076 DOI: 10.1093/jmammal/gyab050] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2020] [Accepted: 04/02/2021] [Indexed: 01/05/2023] Open
Abstract
Recent studies have revealed that western populations of little brown bats (Myotis lucifugus) in North America exhibit different hibernation behavior than their eastern counterparts. Understanding these differences is essential for assessing the risk white-nose syndrome (WNS) poses to western bat populations. We used acoustic monitoring and radiotelemetry to study the overwintering behavior of little brown bats near Juneau, Alaska during 2011-2014. Our objectives were to identify the structures they use for hibernation, measure the microclimates within those structures, and determine the timing of immergence and emergence and the length of the hibernation season. We radiotracked 10 little brown bats to underground hibernacula dispersed along two ridge systems. All hibernacula were ≤ 24.2 km from where the bats were captured. Eight bats hibernated in the "Milieu Souterrain Superficiel" (MSS), a network of air-filled underground voids between the rock fragments found in scree (talus) deposits. Two bats hibernated in holes in the soil beneath the root system of a tree or stump (rootball). At least two hibernacula in the MSS were reused in subsequent years. Average MSS and rootball temperatures were warmer and more stable than ambient temperature and were well below the optimal growth range of the fungus that causes WNS. Temperatures in the MSS dropped below freezing, but MSS temperatures increased with depth, indicating bats could avoid subfreezing temperatures by moving deeper into the MSS. Relative humidity (RH) approached 100% in the MSS and under rootballs and was more stable than ambient RH, which also was high, but dropped substantially during periods of extreme cold. Acoustic monitoring revealed that bats hibernated by late October and began emerging by the second week of April; estimates of minimum length of the hibernation season ranged from 156 to 190 days. The cold temperatures, dispersed nature of the hibernacula, and close proximity of hibernacula to summering areas may slow the spread and reduce the impacts of WNS on local populations of little brown bats.
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Affiliation(s)
- Karen M Blejwas
- Alaska Department of Fish & Game, Threatened, Endangered and Diversity Program, Juneau, AK, USA
| | - Grey W Pendleton
- Alaska Department of Fish & Game, Threatened, Endangered and Diversity Program, Juneau, AK, USA
| | - Michael L Kohan
- Alaska Department of Fish & Game, Threatened, Endangered and Diversity Program, Juneau, AK, USA
| | - Laura O Beard
- Alaska Department of Fish & Game, Threatened, Endangered and Diversity Program, Juneau, AK, USA
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12
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Long-term patterns of cave-exiting activity of hibernating bats in western North America. Sci Rep 2021; 11:8175. [PMID: 33854126 PMCID: PMC8046793 DOI: 10.1038/s41598-021-87605-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Accepted: 03/17/2021] [Indexed: 11/08/2022] Open
Abstract
Understanding frequency and variation of cave-exiting activity after arousal from torpor of hibernating bats is important for bat ecology and conservation, especially considering white-nose syndrome. In winter from 2011 to 2018, we acoustically monitored, and counted in hibernacula, two species of conservation concern-western small-footed myotis (Myotis ciliolabrum) and Townsend's big-eared bats (Corynorhinus townsendii)-in 9 caves located in important habitat for these species in western North America. We investigated if cave-exiting activity differed by species, cave, number of hibernating bats, moon phase, and weather variables. Both species exited hibernacula during all winter months, but most activity occurred in March followed by November. Although we counted almost 15 times more Townsend's big-eared bats during hibernacula surveys, we documented western small-footed myotis exiting caves 3 times more than Townsend's big-eared bats. Cave-exiting activity increased with increasing number of hibernating bats, but more so for western small-footed myotis. Both species of bats were active during warm weather and low wind speeds. Western small-footed myotis were more active during colder temperatures, higher wind speeds, and greater change in barometric pressure than Townsend's big-eared bats. Our results provide a long-term dataset of cave-exiting activity after arousal from torpor during hibernation for these species before the arrival of white-nose syndrome.
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Abstract
AbstractNatural hibernation sites used by bats in areas that lack cave features have long remained unresolved. To investigate hibernation site selection and winter activity of boreal bats, we recorded bat calls using passive acoustic monitoring at 16 sites in South-Western Finland. These sites included four rock outcrops with crevices and cave features, three glacial erratics or boulder fields, three ancient shores, three root cellars and three control sites where we did not expect bats to be overwintering. Our results revealed echolocation calls of Eptesicus nilssonii, Plecotus auritus and Myotis sp. We recorded significantly more activity near rock outcrops compared to other habitats, excluding root cellars. We also found that ambient temperature had a positive effect on bat activity and found evidence that P. auritus may be using low barometric pressure as a proxy for suitable foraging conditions during the winter. Our results suggest that rock outcrops may be more important to bats than previously acknowledged, highlighting the need to take these sites in account in planning of conservation measures. Furthermore, our findings underline the suitability of using acoustic monitoring in homing on hibernation sites that are not otherwise accessible.
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Arndt RJ, Lima SL. Landscape-wide flight activity by wintering bats predictably follows pulses of warmth in the Midwestern United States. J Mammal 2020. [DOI: 10.1093/jmammal/gyaa088] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
During winter hibernation, bats may become active for a variety of reasons. Such winter activity occurs at or near hibernacula, but the degree to which this activity represents long-distance travel across a wider landscape largely is unstudied. We documented patterns in landscape-wide winter activity across a west-central Indiana study site, providing some new insights into winter flight activity. We deployed acoustic recording devices in areas without any known hibernacula, each night from December through March over three consecutive winters. Twilight temperatures (1 h post-sunset) ranged from −23°C to 21°C across three winters. We recorded 4,392 call files and attributed 89% to a phonic group based on characteristic frequencies. Flight activity was recorded at all stations and during all winter months. Nightly activity mainly was a function of the temperature on that night. We recorded low-phonic bats (most likely big brown bats, Eptesicus fuscus) down to −4°C, but most activity occurred when twilight temperatures were > 0°C. Mid-phonic bat activity (most likely eastern red bats, Lasiurus borealis) occurred when temperatures were > 0°C, with most activity occurring when temperatures were > 5°C. Wind speeds > 6 m/s tended to suppress activity. The duration of inactive periods during cold spells had no effect on activity during subsequent warm nights, indicating no increasing drive for activity following long periods of inactivity. Most activity occurred within a few hours of sunset, regardless of temperature. Little pre-sunset activity was recorded in low-phonic bats, but mid-phonic bats sometimes were active in the hour before sunset. Our results suggest widespread and potentially long-distance travel by bats across our study area during warm periods, but the impetus behind this activity remains unclear.
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Affiliation(s)
- Robert J Arndt
- Department of Natural Sciences, Northwest Missouri State University, Maryville, MO, USA
| | - Steven L Lima
- Department of Biology, Indiana State University, Terre Haute, IN, USA
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Wilsterman K, Ballinger MA, Williams CM. A unifying, eco‐physiological framework for animal dormancy. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13718] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Kathryn Wilsterman
- Biological Sciences University of Montana Missoula MT USA
- Integrative Biology University of California Berkeley CA USA
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Parker KA, Li H, Kalcounis-Rueppell MC. Species-specific environmental conditions for winter bat acoustic activity in North Carolina, United States. J Mammal 2020. [DOI: 10.1093/jmammal/gyaa133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Low winter temperatures are a major driver of hibernation and migration in temperate North American bats. Hibernation and migration in turn affect bat mortality via white-nose syndrome and collisions with wind turbines. To describe winter bat acoustic activity across a wide temperature gradient and to understand species-specific responses to low temperatures, we recorded nightly acoustic activity of bats at 15 sites across the state of North Carolina, United States, from December through February 2016 – 2018. Bat acoustic activity was recorded at all sites during both winters. Nightly probability of bat acoustic presence regressed positively on ambient temperature. Nightly probability of presence in Lasionycteris noctivagans (silver-haired bat) and Eptesicus fuscus (big brown bat) regressed negatively on wind speed. The mean probability of presence within the same winter condition was highest for L. noctivagans, followed by E. fuscus, Perimyotis subflavus (tricolored bat), and Lasiurus cinereus (hoary bat). Differences in species’ mean body weight and roosting preference explained part of the variation of the species-specific probability of presence. Our results can be used to predict bat acoustic presence for these species across the southeastern United States in winter, and better understand the potential threats to bats such as white-nose syndrome and wind turbine interactions.
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Affiliation(s)
- Kevin A Parker
- Department of Biology, University of North Carolina - Greensboro, Greensboro, NC, USA
| | - Han Li
- Department of Biology, University of North Carolina - Greensboro, Greensboro, NC, USA
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Hicks LL, Schwab NA, Homyack JA, Jones JE, Maxell BA, Burkholder BO. A statistical approach to white-nose syndrome surveillance monitoring using acoustic data. PLoS One 2020; 15:e0241052. [PMID: 33091068 PMCID: PMC7580964 DOI: 10.1371/journal.pone.0241052] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 10/07/2020] [Indexed: 11/19/2022] Open
Abstract
Traditional pathogen surveillance methods for white-nose syndrome (WNS), the most serious threat to hibernating North American bats, focus on fungal presence where large congregations of hibernating bats occur. However, in the western USA, WNS-susceptible bat species rarely assemble in large numbers and known winter roosts are uncommon features. WNS increases arousal frequency and activity of infected bats during hibernation. Our objective was to explore the effectiveness of acoustic monitoring as a surveillance tool for WNS. We propose a non-invasive approach to model pre-WNS baseline activity rates for comparison with future acoustic data after WNS is suspected to occur. We investigated relationships among bat activity, ambient temperatures, and season prior to presence of WNS across forested sites of Montana, USA where WNS was not known to occur. We used acoustic monitors to collect bat activity and ambient temperature data year-round on 41 sites, 2011-2019. We detected a diverse bat community across managed (n = 4) and unmanaged (n = 37) forest sites and recorded over 5.37 million passes from bats, including 13 identified species. Bats were active year-round, but positive associations between average of the nightly temperatures by month and bat activity were strongest in spring and fall. From these data, we developed site-specific prediction models for bat activity to account for seasonal and annual temperature variation prior to known occurrence of WNS. These prediction models can be used to monitor changes in bat activity that may signal potential presence of WNS, such as greater than expected activity in winter, or less than expected activity during summer. We propose this model-based method for future monitoring efforts that could be used to trigger targeted sampling of individual bats or hibernacula for WNS, in areas where traditional disease surveillance approaches are logistically difficult to implement or because of human-wildlife transmission concerns from COVID-19.
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Affiliation(s)
| | | | | | - Jay E. Jones
- Weyerhaeuser, Seattle, WA, United States of America
| | - Bryce A. Maxell
- Montana Natural Heritage Program, Helena, Montana, United States of America
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Stevens RD, Garcia CJ, Madden MA, Gregory BB, Perry RW. Seasonal Changes in the Active Bat Community of the Kisatchie National Forest, Louisiana. SOUTHEAST NAT 2020. [DOI: 10.1656/058.019.0308] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Richard D. Stevens
- Department of Natural Resources Management, Texas Tech University, Lubbock, TX 79409
| | - Carlos J. Garcia
- Department of Natural Resources Management, Texas Tech University, Lubbock, TX 79409
| | - Macy A. Madden
- Department of Biological Sciences, Texas Tech University, Lubbock, TX 79409
| | - Beau B. Gregory
- Louisiana Natural Heritage Program, Louisiana Department of Wildlife and Fisheries, 1213 N. Lakeshore Drive, Lake Charles, LA 70601
| | - Roger W. Perry
- Southern Research Station, United States Forest Service, PO Box 1270, Hot Springs, AR 71902
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Blomberg AS, Vasko V, Salonen S, Pētersons G, Lilley TM. First record of a Nathusius’ pipistrelle (Pipistrellus nathusii) overwintering at a latitude above 60°N. MAMMALIA 2020. [DOI: 10.1515/mammalia-2020-0019] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Highly mobile species are considered to be the first to respond to climate change by transforming their ranges of distribution. There is evidence suggesting that Pipistrellus nathusii, a species capable of long-distance migration, is expanding both its reproduction and overwintering ranges to the North. We recorded the echolocation calls of bats at 16 sites in South-Western Finland on two consecutive winters, and detected calls of P. nathusii at one of the sites throughout the second winter. To our knowledge, this is the northernmost record of an overwintering P. nathusii, and contributes to evidence that the species is already responding to climate change.
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Affiliation(s)
- Anna S. Blomberg
- Department of Biology , University of Turku , Vesilinnantie 5 , Turku 20014 , Finland
| | - Ville Vasko
- Finnish Museum of Natural History , University of Helsinki , P. Rautatiekatu 13, PL17 , 00100 Helsinki , Finland
| | - Saku Salonen
- Department of Biology , University of Turku , Vesilinnantie 5 , Turku 20014 , Finland
| | - Gunārs Pētersons
- Latvian University of Life Sciences and Technologies , Lielā iela 2, Jelgava , LV-3001 , Latvia
| | - Thomas M. Lilley
- Finnish Museum of Natural History , University of Helsinki , P. Rautatiekatu 13, PL17 , 00100 Helsinki , Finland
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Findlay SV, Barclay RMR. Acoustic Surveys for Bats are Improved by Taking Habitat Type into Account. WILDLIFE SOC B 2020. [DOI: 10.1002/wsb.1053] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Stephanie V. Findlay
- Department of Biological SciencesUniversity of Calgary, 2500 University Drive NWCalgary AB Canada T2N 1N4
| | - Robert M. R. Barclay
- Department of Biological SciencesUniversity of Calgary, 2500 University Drive NWCalgary AB Canada T2N 1N4
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21
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White JA, Freeman PW, Otto HW, Lemen CA. Winter Use of a Rock Crevice by Northern Long-Eared Myotis (Myotis septentrionalis) in Nebraska. WEST N AM NATURALIST 2020. [DOI: 10.3398/064.080.0114] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Jeremy A. White
- Department of Biology, University of Nebraska at Omaha, Omaha, NE 68182
| | - Patricia W. Freeman
- School of Natural Resources and University of Nebraska State Museum, University of Nebraska–Lincoln, Lincoln, NE 68583
| | - Hans W. Otto
- Department of Ecology and Evolutionary Biology, University of Arizona, Tuscon, AZ 85721
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Haase CG, Fuller NW, Hranac CR, Hayman DTS, McGuire LP, Norquay KJO, Silas KA, Willis CKR, Plowright RK, Olson SH. Incorporating evaporative water loss into bioenergetic models of hibernation to test for relative influence of host and pathogen traits on white-nose syndrome. PLoS One 2019; 14:e0222311. [PMID: 31671100 PMCID: PMC6822741 DOI: 10.1371/journal.pone.0222311] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 10/08/2019] [Indexed: 12/29/2022] Open
Abstract
Hibernation consists of extended durations of torpor interrupted by periodic arousals. The ‘dehydration hypothesis’ proposes that hibernating mammals arouse to replenish water lost through evaporation during torpor. Arousals are energetically expensive, and increased arousal frequency can alter survival throughout hibernation. Yet we lack a means to assess the effect of evaporative water loss (EWL), determined by animal physiology and hibernation microclimate, on torpor bout duration and subsequent survival. White-nose syndrome (WNS), a devastating disease impacting hibernating bats, causes increased frequency of arousals during hibernation and EWL has been hypothesized to contribute to this increased arousal frequency. WNS is caused by a fungus, which grows well in humid hibernaculum environments and damages wing tissue important for water conservation. Here, we integrated the effect of EWL on torpor expression in a hibernation energetics model, including the effects of fungal infection, to determine the link between EWL and survival. We collected field data for Myotis lucifugus, a species that experiences high mortality from WNS, to gather parameters for the model. In saturating conditions, we predicted healthy bats experience minimal mortality. Infected bats, however, suffer high fungal growth in highly saturated environments, leading to exhaustion of fat stores before spring. Our results suggest that host adaptation to humid environments leads to increased arousal frequency from infection, which drives mortality across hibernaculum conditions. Our modified hibernation model provides a tool to assess the interplay between host physiology, hibernaculum microclimate, and diseases such as WNS on winter survival.
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Affiliation(s)
- Catherine G. Haase
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, United States of America
- * E-mail:
| | - Nathan W. Fuller
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, United States of America
| | - C. Reed Hranac
- Molecular Epidemiology and Public Health Laboratory, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
| | - David T. S. Hayman
- Molecular Epidemiology and Public Health Laboratory, Hopkirk Research Institute, Massey University, Palmerston North, New Zealand
| | - Liam P. McGuire
- Department of Biological Sciences, Texas Tech University, Lubbock, Texas, United States of America
| | | | - Kirk A. Silas
- Wildlife Conservation Society, Wildlife Health Program, Bronx, New York, United States of America
| | | | - Raina K. Plowright
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana, United States of America
| | - Sarah H. Olson
- Wildlife Conservation Society, Wildlife Health Program, Bronx, New York, United States of America
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23
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Species Richness and Seasonality of Bat Occupancy on Northwestern National Wildlife Refuges. JOURNAL OF FISH AND WILDLIFE MANAGEMENT 2019. [DOI: 10.3996/032019-jfwm-019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abstract
Bats are critical to ecosystem integrity but are being threatened by a variety of disease and anthropogenic stressors. Further, information is generally lacking on basic parameters necessary for long-term bat conservation in North America, including the timing of seasonal activity and location of overwintering sites. Between 2011 and 2016, we used passive acoustic recording equipment to collect and analyze 115,855 bat calls from six National Wildlife Refuges across three geographic areas in the northwestern United States; the majority of the data was collected from 2014 to 2015. We documented the presence of 16 species, with species richness varying from 6 to 15 species across sampled Refuges. This includes detection of two species outside of their expected ranges: western red bat Lasiurus blossevillii were found in the Great Basin and western pipistrelle Pipistrellus hysperus were found in the Northern Rockies. Overwintering bats were found across all three geographic areas, although only one species, western pipistrelle, was documented as active year round on more than one Refuge. Six species of bats were also identified as potentially overwintering within their respective areas. For suspected nonoverwintering species, including those considered susceptible to white-nose syndrome, dates of first detections began in early March to early May and last detections between early October and early November. Public lands established for conservation can provide important monitoring and conservation resources for bats.
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Halliday W, Pine M, Insley S, Soares R, Kortsalo P, Mouy X. Acoustic detections of Arctic marine mammals near Ulukhaktok, Northwest Territories, Canada. CAN J ZOOL 2019. [DOI: 10.1139/cjz-2018-0077] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The Arctic marine environment is changing rapidly through a combination of sea ice loss and increased anthropogenic activity. Given these changes can affect marine animals in a variety of ways, understanding the spatial and temporal distributions of Arctic marine animals is imperative. We use passive acoustic monitoring to examine the presence of marine mammals near Ulukhaktok, Northwest Territories, Canada, from October 2016 to April 2017. We documented bowhead whale (Balaena mysticetus Linnaeus, 1758) and beluga whale (Delphinapterus leucas (Pallas, 1776)) vocalizations later into the autumn than expected, and we recorded bowhead whales in early April. We recorded ringed seal (Pusa hispida (Schreber, 1775)) vocalizations throughout our deployment, with higher vocal activity than in other studies and with peak vocal activity in January. We recorded bearded seals (Erignathus barbatus (Erxleben, 1777)) throughout the deployment, with peak vocal activity in February. We recorded lower bearded seal vocal activity than other studies, and almost no vocal activity near the beginning of the spring breeding season. Both seal species vocalized more when ice concentration was high. These patterns in vocal activity document the presence of each species at this site over autumn and winter and are a useful comparison for future monitoring.
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Affiliation(s)
- W.D. Halliday
- Wildlife Conservation Society Canada, 169 Titanium Way, Whitehorse, YT Y1A 0E9, Canada
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 5C2, Canada
| | - M.K. Pine
- Wildlife Conservation Society Canada, 169 Titanium Way, Whitehorse, YT Y1A 0E9, Canada
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 5C2, Canada
| | - S.J. Insley
- Wildlife Conservation Society Canada, 169 Titanium Way, Whitehorse, YT Y1A 0E9, Canada
- Department of Biology, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 5C2, Canada
| | - R.N. Soares
- Wildlife Conservation Society Canada, 169 Titanium Way, Whitehorse, YT Y1A 0E9, Canada
| | - P. Kortsalo
- Wildlife Conservation Society Canada, 169 Titanium Way, Whitehorse, YT Y1A 0E9, Canada
| | - X. Mouy
- School of Earth and Ocean Sciences, University of Victoria, 3800 Finnerty Road, Victoria, BC V8P 5C2, Canada
- JASCO Applied Science Ltd., 2305-4464 Markham Street, Victoria, BC V8Z 7X8, Canada
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Weller TJ, Rodhouse TJ, Neubaum DJ, Ormsbee PC, Dixon RD, Popp DL, Williams JA, Osborn SD, Rogers BW, Beard LO, McIntire AM, Hersey KA, Tobin A, Bjornlie NL, Foote J, Bachen DA, Maxell BA, Morrison ML, Thomas SC, Oliver GV, Navo KW. A review of bat hibernacula across the western United States: Implications for white-nose syndrome surveillance and management. PLoS One 2018; 13:e0205647. [PMID: 30379854 PMCID: PMC6209190 DOI: 10.1371/journal.pone.0205647] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 09/30/2018] [Indexed: 01/24/2023] Open
Abstract
Efforts to conserve bats in the western United States have long been impeded by a lack of information on their winter whereabouts, particularly bats in the genus Myotis. The recent arrival of white-nose syndrome in western North America has increased the urgency to characterize winter roost habitats in this region. We compiled 4,549 winter bat survey records from 2,888 unique structures across 11 western states. Myotis bats were reported from 18.5% of structures with 95% of aggregations composed of ≤10 individuals. Only 11 structures contained ≥100 Myotis individuals and 6 contained ≥500 individuals. Townsend’s big-eared bat (Corynorhinus townsendii) were reported from 38% of structures, with 72% of aggregations composed of ≤10 individuals. Aggregations of ≥100 Townsend’s big-eared bats were observed at 41 different caves or mines across 9 states. We used zero-inflated negative binomial regression to explore biogeographic patterns of winter roost counts. Myotis counts were greater in caves than mines, in more recent years, and in more easterly longitudes, northerly latitudes, higher elevations, and in areas with higher surface temperatures and lower precipitation. Townsend’s big-eared bat counts were greater in caves, during more recent years, and in more westerly longitudes. Karst topography was associated with higher Townsend’s big-eared bat counts but did not appear to influence Myotis counts. We found stable or slightly-increasing trends over time in counts for both Myotis and Townsend’s big-eared bats from 82 hibernacula surveyed ≥5 winters since 1990. Highly-dispersed winter roosting of Myotis in the western USA complicates efforts to monitor population trends and impacts of disease. However, our results reveal opportunities to monitor winter population status of Townsend’s big-eared bats across this region.
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Affiliation(s)
- Theodore J. Weller
- USDA Forest Service, Pacific Southwest Research Station, Arcata, California, United States of America
- * E-mail:
| | - Thomas J. Rodhouse
- National Park Service Upper Columbia Basin Network, Bend, Oregon, United States of America
| | - Daniel J. Neubaum
- Colorado Parks and Wildlife, Terrestrial Section, Grand Junction, Colorado, United States of America
| | - Patricia C. Ormsbee
- USDA Forest Service, Pacific Northwest Region, Eugene, Oregon, United States of America
| | - Rita D. Dixon
- Idaho Department of Fish and Game, Boise, Idaho, United States of America
| | - Diana L. Popp
- Oregon State University – Cascades Campus, Human & Ecosystem Resiliency & Sustainability Lab, Bend, Oregon, United States of America
| | - Jason A. Williams
- Nevada Department of Wildlife, Ely, Nevada, United States of America
| | - Scott D. Osborn
- California Department of Fish and Wildlife, Nongame Wildlife Program, Wildlife Branch, Sacramento, California, United States of America
| | - Bruce W. Rogers
- Western Cave Conservancy, Newcastle, California, United States of America
| | - Laura O. Beard
- Wyoming Game and Fish Department, Nongame Program, Lander, Wyoming, United States of America
| | - Angela M. McIntire
- Arizona Game and Fish Department, Phoenix, Arizona, United States of America
| | - Kimberly A. Hersey
- Utah Division of Wildlife Resources, Salt Lake City, Utah, United States of America
| | - Abigail Tobin
- Washington Department of Fish and Wildlife, Olympia, Washington, United States of America
| | - Nichole L. Bjornlie
- Wyoming Game and Fish Department, Nongame Program, Lander, Wyoming, United States of America
| | - Jennifer Foote
- National Speleological Society, Santa Fe, New Mexico, United States of America
| | - Dan A. Bachen
- Montana Natural Heritage Program, Helena, Montana, United States of America
| | - Bryce A. Maxell
- Montana Natural Heritage Program, Helena, Montana, United States of America
| | - Michael L. Morrison
- Texas A&M University, Department of Wildlife and Fisheries Sciences, College Station, Texas, United States of America
| | - Shawn C. Thomas
- Bat Conservation International, Subterranean Program, Olympia, Washington, United States of America
| | - George V. Oliver
- Utah Division of Wildlife Resources, Salt Lake City, Utah, United States of America
| | - Kirk W. Navo
- Colorado Division of Wildlife, Monte Vista, Colorado, United States of America
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Neubaum DJ. Unsuspected retreats: autumn transitional roosts and presumed winter hibernacula of little brown myotis in Colorado. J Mammal 2018. [DOI: 10.1093/jmammal/gyy120] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Daniel J Neubaum
- Terrestrial Section, Colorado Parks and Wildlife, Independent Avenue, Grand Junction, CO, USA
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27
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Reynolds DS, Shoemaker K, Oettingen SV, Najjar S. High Rates of Winter Activity and Arousals in Two New England Bat Species: Implications for a Reduced White-Nose Syndrome Impact? Northeast Nat (Steuben) 2017. [DOI: 10.1656/045.024.s720] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- D. Scott Reynolds
- St. Paul's School, Concord, NH 03301
- North East Ecological Services, Concord, NH 03301
| | - Kevin Shoemaker
- Natural Resources and Environmental Science, University of Nevada, Reno, NV 89557
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Klüg-Baerwald BJ, Lausen CL, Willis CKR, Brigham RM. Home is where you hang your bat: winter roost selection by prairie-living big brown bats. J Mammal 2017. [DOI: 10.1093/jmammal/gyx039] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
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29
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Martin CM, Arnett EB, Stevens RD, Wallace MC. Reducing bat fatalities at wind facilities while improving the economic efficiency of operational mitigation. J Mammal 2017. [DOI: 10.1093/jmammal/gyx005] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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30
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Klüg-Baerwald BJ, Brigham RM. Hung out to dry? Intraspecific variation in water loss in a hibernating bat. Oecologia 2017; 183:977-985. [PMID: 28213638 DOI: 10.1007/s00442-017-3837-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 02/07/2017] [Indexed: 02/05/2023]
Abstract
Hibernation is a period of water deficit for some small mammals, and humidity strongly influences hibernation patterns. Dry conditions reduce length of torpor bouts, stimulate arousals, and decrease overwinter survival. To mitigate these effects, many small mammals hibernate in near saturated (100% RH) conditions. However, big brown bats (Eptesicus fuscus) hibernate in a wider variety of conditions and tolerate lower humidity than most other bats. To assess arid tolerance in this species, we compared torpid metabolic rates (TMR) and rates of total evaporative water loss (TEWL) between two populations of E. fuscus with differing winter ecologies: one that hibernates in humid karst caves and one that hibernates in relatively dry rock crevices. We used flow-through respirometry to measure TMR and TEWL of bats in humid and dry conditions. Torpid metabolic rates did not differ between populations or with humidity treatments. Rates of TEWL were similar between populations in humid conditions, but higher for cave-hibernating bats than crevice-hibernating bats in dry conditions. Our results suggest that E. fuscus hibernating in arid environments have mechanisms to decrease evaporative water loss that are not evident at more humid sites. Drought tolerance may facilitate the sedentary nature of the species, allowing them to tolerate more variable microclimates during hibernation and thus increasing the availability of overwintering habitat. The ability to survive arid conditions may also lessen the susceptibility of E. fuscus to diseases that affect water balance.
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Affiliation(s)
| | - R Mark Brigham
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK, Canada
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McGuire L, Muise K, Shrivastav A, Willis C. No evidence of hyperphagia during prehibernation in a northern population of little brown bats (Myotis lucifugus). CAN J ZOOL 2016. [DOI: 10.1139/cjz-2016-0110] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
During autumn, temperate bats must deposit fat stores for hibernation. Populations at high latitudes face four challenges: a shorter active season and shorter nights during the active season (less time to accumulate fat), a longer hibernation period (larger fat store needed), and colder nights (reduced prey availability). Mating also occurs during the prehibernation period, placing time constraints for mating and fattening on northern populations. We tested the hypothesis that these factors constrain prehibernation foraging in northern populations of little brown bats (Myotis lucifugus (Le Conte, 1831)). We measured plasma triglyceride concentration to study prehibernation fueling rates of a population near the northern range limit of the species and compared our results with previously published results from a more southern population. In contrast to bats at the lower latitude, we found consistently low concentrations of plasma triglycerides, indicating a low fuelling rate throughout the prehibernation period. However, despite an apparently low fuelling rate, bats achieved a substantially greater body mass. The discrepancy between populations suggests that environmental constraints lead northern populations to employ different behavioural or physiological strategies to prepare for hibernation.
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Affiliation(s)
- L.P. McGuire
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
| | - K.A. Muise
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
| | - A. Shrivastav
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
| | - C.K.R. Willis
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
- Department of Biology, University of Winnipeg, 515 Portage Avenue, Winnipeg, MB R3B 2E9, Canada
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Klüg-Baerwald B, Gower L, Lausen C, Brigham R. Environmental correlates and energetics of winter flight by bats in southern Alberta, Canada. CAN J ZOOL 2016. [DOI: 10.1139/cjz-2016-0055] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Winter activity of bats is common, yet poorly understood. Other studies suggest a relationship between winter activity and ambient temperature, particularly temperature at sunset. We recorded echolocation calls to determine correlates of hourly bat activity in Dinosaur Provincial Park, Alberta, Canada. We documented bat activity in temperatures as low as −10.4 °C. We observed big brown bats (Eptesicus fuscus (Palisot de Beauvois, 1796)) flying at colder temperatures than species of Myotis bats (genus Myotis Kaup, 1829). We show that temperature and wind are important predictors of winter activity by E. fuscus and Myotis, and that Myotis may also use changes in barometric pressure to cue activity. In the absence of foraging opportunity, we suggest these environmental factors relate to heat loss and thus the energetic cost of flight. To understand the energetic consequences of bat flight in cold temperatures, we estimated energy expenditure during winter flights of E. fuscus and little brown myotis (Myotis lucifugus (Le Conte, 1831)) using species-specific parameters. We estimated that winter flight uses considerable fat stores and that flight thermogenesis could mitigate energetic costs by 20% or more. We also show that temperature-dependent interspecific differences in winter activity likely stem from differences between species in heat loss and potential for activity–thermoregulatory heat substitution.
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Affiliation(s)
- B.J. Klüg-Baerwald
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
| | - L.E. Gower
- School of Biosciences, Sir Martin Evans Building, Cardiff University, Museum Avenue, Cardiff CF10 3AX, United Kingdom
| | - C.L. Lausen
- Wildlife Conservation Society Canada, P.O. Box 606, Kaslo, BC V0G 1M0, Canada
| | - R.M. Brigham
- Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, SK S4S 0A2, Canada
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Johnson JS, Treanor JJ, Lacki MJ, Baker MD, Falxa GA, Dodd LE, Waag AG, Lee EH. Migratory and winter activity of bats in Yellowstone National Park. J Mammal 2016. [DOI: 10.1093/jmammal/gyw175] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Cichocki J, Łupicki D, Bojarski J, Ważna A. The Impact of the Moon Phases on Winter Activity of the Noctule BatsNyctalus noctula. POLISH JOURNAL OF ECOLOGY 2015. [DOI: 10.3161/15052249pje2015.63.4.014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Hope PR, Bohmann K, Gilbert MTP, Zepeda-Mendoza ML, Razgour O, Jones G. Second generation sequencing and morphological faecal analysis reveal unexpected foraging behaviour by Myotis nattereri (Chiroptera, Vespertilionidae) in winter. Front Zool 2014; 11:39. [PMID: 25093034 PMCID: PMC4108090 DOI: 10.1186/1742-9994-11-39] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2013] [Accepted: 04/28/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Temperate winters produce extreme energetic challenges for small insectivorous mammals. Some bat species inhabiting locations with mild temperate winters forage during brief inter-torpor normothermic periods of activity. However, the winter diet of bats in mild temperate locations is studied infrequently. Although microscopic analyses of faeces have traditionally been used to characterise bat diet, recently the coupling of PCR with second generation sequencing has offered the potential to further advance our understanding of animal dietary composition and foraging behaviour by allowing identification of a much greater proportion of prey items often with increased taxonomic resolution. We used morphological analysis and Illumina-based second generation sequencing to study the winter diet of Natterer's bat (Myotis nattereri) and compared the results obtained from these two approaches. For the first time, we demonstrate the applicability of the Illumina MiSeq platform as a data generation source for bat dietary analyses. RESULTS Faecal pellets collected from a hibernation site in southern England during two winters (December-March 2009-10 and 2010-11), indicated that M. nattereri forages throughout winter at least in a location with a mild winter climate. Through morphological analysis, arthropod fragments from seven taxonomic orders were identified. A high proportion of these was non-volant (67.9% of faecal pellets) and unexpectedly included many lepidopteran larvae. Molecular analysis identified 43 prey species from six taxonomic orders and confirmed the frequent presence of lepidopteran species that overwinter as larvae. CONCLUSIONS The winter diet of M. nattereri is substantially different from other times of the year confirming that this species has a wide and adaptable dietary niche. Comparison of DNA derived from the prey to an extensive reference dataset of potential prey barcode sequences permitted fine scale taxonomic resolution of prey species. The high occurrence of non-volant prey suggests that gleaning allows prey capture at low ambient temperatures when the abundance of flying insects may be substantially reduced. Interesting questions arise as to how M. nattereri might successfully locate and capture some of the non-volant prey species encountered in its faeces. The consumption of lepidopteran larvae such as cutworms suggests that M. nattereri eats agricultural pest species.
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Affiliation(s)
- Paul R Hope
- School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
- Ecological Consultancy Services Ltd, Longdown, Salisbury Road, Shootash SO51 6GA, UK
| | - Kristine Bohmann
- School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
- Section for Evolutionary Genomics, Centre for GeoGenetics, Natural History Museum of Denmark, Copenhagen, Denmark
| | - M Thomas P Gilbert
- Section for Evolutionary Genomics, Centre for GeoGenetics, Natural History Museum of Denmark, Copenhagen, Denmark
| | | | - Orly Razgour
- School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
| | - Gareth Jones
- School of Biological Sciences, University of Bristol, Woodland Road, Bristol BS8 1UG, UK
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Affiliation(s)
- Hayley A. Sherwin
- School of Biological Sciences; Queen's University; Belfast; BT9 7BL; UK
| | - W. Ian Montgomery
- School of Biological Sciences; Queen's University; Belfast; BT9 7BL; UK
| | - Mathieu G. Lundy
- Centre of Irish Bat Research; School of Biological Sciences; Queen's University; Belfast; BT9 7BL; UK
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Halsall AL, Boyles JG, Whitaker JO. Body temperature patterns of big brown bats during winter in a building hibernaculum. J Mammal 2012. [DOI: 10.1644/11-mamm-a-262.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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Warming up for dinner: torpor and arousal in hibernating Natterer's bats (Myotis nattereri) studied by radio telemetry. J Comp Physiol B 2011; 182:569-78. [PMID: 22124860 DOI: 10.1007/s00360-011-0631-x] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2011] [Revised: 11/03/2011] [Accepted: 11/09/2011] [Indexed: 10/15/2022]
Abstract
The frequency and function of arousals during hibernation in free-living mammals are little known. We used temperature-sensitive radio transmitters to measure patterns of torpor, arousal and activity in wild Natterer's bats Myotis nattereri during hibernation. Duration of torpor bouts ranged from 0.06 to 20.4 days with individual means ranging from 0.9 to 8.9 days. Arousals from torpor occurred most commonly coincident with the time (relative to sunset) typical for bats emerging from summer roosts to forage. Bats with lower body condition indices had a shorter average duration of their torpor bouts. We found a non-linear relationship between duration of torpor bout and ambient temperature: the longest average torpor bouts were at temperatures between 2 and 4°C with shorter bouts at lower and higher ambient temperatures. One individual was radio-tracked for ten nights, remained active for an average of 297 min each night and was active for longer on warmer nights. Our results suggest that vespertilionid bats use relatively short torpor bouts during hibernation in a location with a maritime climate. We hypothesise that Natterer's bats time arousals to maximise opportunities for potential foraging during winter although winter feeding is not the sole determinant of arousal as bats still arouse at times when foraging is unlikely.
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Influence of urbanization on demography of little brown bats (Myotis lucifugus) in the prairies of North America. PLoS One 2011; 6:e20483. [PMID: 21857890 PMCID: PMC3154510 DOI: 10.1371/journal.pone.0020483] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2010] [Accepted: 05/02/2011] [Indexed: 11/20/2022] Open
Abstract
Background We address three key gaps in research on urban wildlife ecology: insufficient attention to (1) grassland biomes, (2) individual- and population-level effects, and (3) vertebrates other than birds. We hypothesized that urbanization in the North American Prairies, by increasing habitat complexity (via the proliferation of vertical structures such as trees and buildings), thereby enhancing the availability of day-roosts, tree cover, and insects, would benefit synanthropic bats, resulting in increased fitness among urban individuals. Methodology/Principal Findings Over three years, we captured more than 1,600 little brown bats (Myotis lucifugus) in urban and non-urban riparian sites in and around Calgary, Alberta, Canada. This species dominated bat assemblages throughout our study area, but nowhere more so than in the city. Our data did not support most of our specific predictions. Increased numbers of urban bats did not reflect urbanization-related benefits such as enhanced body condition, reproductive rates, or successful production of juveniles. Instead, bats did best in the transition zone situated between strictly urban and rural areas. Conclusions/Significance We reject our hypothesis and explore various explanations. One possibility is that urban and rural M. lucifugus exhibit increased use of anthropogenic roosts, as opposed to natural ones, leading to larger maternity colonies and higher population densities and, in turn, increased competition for insect prey. Other possibilities include increased stress, disease transmission and/or impacts of noise on urban bats. Whatever the proximate cause, the combination of greater bat population density with decreased body condition and production of juveniles indicates that Calgary does not represent a population source for Prairie bats. We studied a highly synanthropic species in a system where it could reasonably be expected to respond positively to urbanization, but failed to observe any apparent benefits at the individual level, leading us to propose that urban development may be universally detrimental to bats.
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Abstract
AbstractWe studied seasonal variation in the use of winter roosts by five bat species (Eptesicus nilssonii, Myotis brandtii/mystacinus, Myotis daubentonii and Plecotus auritus) in south-east Finland during the winters of 2003/2004 and 2004/2005. At the beginning of the bat hibernation season all species used higher temperatures and humidity than by the season’s end. Hibernacula were at their coldest in mid-hibernation season and became warmer towards the end of the season. However, no species hibernated in warmer locations at the end of the season than in mid-season. Results suggest that bats tend to use different strategies throughout the hibernation season, minimizing the cost of hibernation early in the season by hibernating in warmer locations and minimizing energy expenditure later in the season by hibernating in colder locations. M. brandtii/mystacinus were found in locations with stable temperature and humidity, moving to increasingly stable conditions (chambers, crevices, clusters, ceiling) towards spring. All other species hibernated in more variable microclimates throughout the hibernation season.
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Schorcht W, Bontadina F, Schaub M. Variation of adult survival drives population dynamics in a migrating forest bat. J Anim Ecol 2009; 78:1182-90. [PMID: 19549146 DOI: 10.1111/j.1365-2656.2009.01577.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
1. Variation of survival across time, between sex and ages strongly affect the population dynamics of long-lived species. Bats are extremely long-lived, but the variation of their survival probabilities is poorly studied with reliable methods. 2. We studied annual local survival probabilities of the migratory Leisler's bats Nyctalus leisleri based on capture-recapture data from 1119 individuals sampled in bat boxes over 20 years in eastern Germany. We assessed variation in survival between sex and age classes, estimated the temporal variance of survival and tested whether survival was affected by weather during hibernation or pregnancy. 3. Among females, our analyses revealed two groups of individuals present with different roosting occupancy, survival and/or dispersal. Local survival of locally born females increased with age [first year: 0.45 +/- 0.04 (SE); later: 0.76 +/- 0.04] and the high recapture probabilities indicate regular presence in the roosts. Recapture probabilities and local survival of foreign adult females were significantly lower, indicating less frequent presence in the roosts and stronger dispersal from the study area. 4. In adult males, locally born and foreign individuals were nearly identical regarding survival and recapture, indicating a more homogenous group. Local survival was very low in the first year (0.04 +/- 0.08), most likely caused by strong natal dispersal. It further increased with age (second year: 0.55 +/- 0.20, later: 0.69 +/- 0.07). 5. Survival probabilities of all females varied significantly and in parallel across time, suggesting that a common environmental factor was operating which affected all individuals similarly. Spring temperature and winter North Atlantic Oscillation explained maximally 9% each of the variation in first year and adult female survival. In contrast to our expectations, the temporal variance of first-year survival was lower than that of adult survival. 6. We found evidence of a complicated social population structure of female Leisler's bats. Our analyses suggest that their population dynamics are driven to a large amount by variation of survival, in particular by adult survival. The reason for the major temporal variations remains to be identified.
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Affiliation(s)
- Wigbert Schorcht
- NACHTaktiv-Bat Research, Kleffelgasse 6, Walldorf/Werra, Germany
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Skowronski MD, Brock Fenton M. Detecting Bat Calls: An Analysis of Automated Methods. ACTA CHIROPTEROLOGICA 2009. [DOI: 10.3161/150811009x465811] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Scanlon AT, Petit S. Effects of site, time, weather and light on urban bat activity and richness: considerations for survey effort. WILDLIFE RESEARCH 2008. [DOI: 10.1071/wr08035] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
To maximise bat retention in urban environments, efficient bat monitoring is needed, but the factors that influence survey results for urban bats are unclear. We used echolocation call detectors (n = 378 detector-nights from November 2005 to October 2006) to assess bat activity among different sites in the Adelaide City parklands, temporal variations in activity (hourly, nightly, monthly), and responses to weather and light (artificial and moon). Bat species did not occur evenly in urban conditions; dark parks were more important for bat diversity and activity (six species groups in the darkest park) than were artificially lit parkland areas (three species groups in the flood-lit park). Gould’s wattled bat (Chalinolobus gouldii) and Mormopterus species 4 (94% of calls) were advantaged in urban parklands, being the only species recorded when lights were on at sports parks, whereas five species groups occurred when the lights were off. Minimal bat activity was recorded in the first 2 h after civil twilight, suggesting that bats may roost outside the city and commute nightly into parklands. Bat activity increased with temperature, with a burst in activity occurring after 7°C. Rainfall (>1 mm/24 h) and moon illumination at midnight did not influence activity. Urban environments should provide diversity to attract a diverse assemblage of bat species. Activity fluctuated among sites, nights, and across the year, indicating that large sample sizes over long periods of time are required to monitor and survey bats reliably with detectors.
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BOYLES JUSTING, DUNBAR MIRANDAB, WHITAKER JOHNO. Activity following arousal in winter in North American vespertilionid bats. Mamm Rev 2006. [DOI: 10.1111/j.1365-2907.2006.00095.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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