Kirk Navo - Academia.edu (original) (raw)

Papers by Kirk Navo

Research paper thumbnail of Intraspecific comparison of population structure, genetic diversity, and dispersal among three subspecies of Townsend’s big-eared bats, Corynorhinus townsendii townsendii, C. t. pallescens, and the endangered C. t. virginianus

Conservation Genetics, 2008

Research paper thumbnail of Small Mammals of Winter Wheat and Grain Sorghum Croplands in West-Central Kansas

Research paper thumbnail of Colorado bat conservation plan

construction, water impoundments, blast ing of cl iffs for avalanche comrol) that impact cliff fa... more construction, water impoundments, blast ing of cl iffs for avalanche comrol) that impact cliff faces or rock outcrops. V. GAPS rN KNOWLEDGE: Litt le or no information known 011 popu lation treads, winter roosting requirements, winter range, importance of snags as summer roosts, and use and acceptance of bat gates. More information is a.lso needed on foraging requirements.

Research paper thumbnail of Observations of swarming by bats and band recoveries in Colorado

Research paper thumbnail of Examination of Fungal Diversity Present on Mexican Free-Tailed Bats, Tadarida Brasiliensis Mexicana, in Colorado

The Southwestern Naturalist

Research paper thumbnail of Silver-Haired Bats Associated with Abandoned Mines in Colorado Provide Insights Into Winter Habitat and Roost Use

Western North American Naturalist

Research paper thumbnail of Guidelines for Defining Biologically Important Bat Roosts: A Case Study from Colorado

Journal of Fish and Wildlife Management, 2017

Conservation of roosts is regularly recommended as a strategy to decrease the risk of threats to ... more Conservation of roosts is regularly recommended as a strategy to decrease the risk of threats to local bat populations (e.g., white-nose syndrome). Determining whether a roost site plays a meaningful role in maintaining a local bat population can be difficult given the variability found in roost structure type, and use by season, duration, and sex. Here we provide land managers and biologists with guidelines to aid in the decision process for determining which roosts are biologically important in maintaining healthy bat populations at a local scale. We define methods for determining biologically important roost sites and provide a case study of their use on bat roosts in Colorado. To be considered biologically important, we suggest that a roost meet two primary criteria: 1) it is considered a hibernaculum, maternity roost, transient roost, colonial bachelor roost, or fall swarming site used by bat species that are gregarious roosters, hibernators, or are known to swarm, and 2) if th...

Research paper thumbnail of Small Mammals of Winter Wheat and Grain Sorghum Croplands in West-Central Kansas

Research paper thumbnail of Allen's Big-Eared Bat (Idionycteris phyllotis) Documented in Colorado Based on Recordings of its Distinctive Echolocation Call

The Southwestern Naturalist, 2009

Allen's big-eared bat (Idionycteris phyllotis) inhabits much of the southwestern USA, but has not... more Allen's big-eared bat (Idionycteris phyllotis) inhabits much of the southwestern USA, but has not been documented in Colorado. We recorded echolocation calls consistent with I. phyllotis near La Sal Creek, Montrose County, Colorado. Based on characteristics of echolocation calls and flight behavior, we conclude that the echolocation calls described here were emitted by I. phyllotis and that they represent the first documentation of this species in Colorado.

Research paper thumbnail of Distribution of the Big Free-Tailed Bat (Nyctinomops macrotis) in Colorado

The Southwestern Naturalist, 2001

... Thanks to CA Jones and the Denver Muse-um of Nature and Science for assistance with speci-men... more ... Thanks to CA Jones and the Denver Muse-um of Nature and Science for assistance with speci-mens, J. Pape for providing Department of Public Health and Environment records, and KM Canes-torp and T. Laurion for providing the juvenile spec-imen. ...

Research paper thumbnail of Hibernacula selection by Townsend's big-Eared bat in southwestern Colorado

The Journal of Wildlife Management, 2011

In western United States, both mine reclamations and renewed mining at previously abandoned mines... more In western United States, both mine reclamations and renewed mining at previously abandoned mines have increased substantially in the last decade. This increased activity may adversely impact bats that use these mines for roosting. Townsend's big-eared bat (Corynorhinus townsendii) is a species of conservation concern that may be impacted by ongoing mine reclamation and renewed mineral extraction. To help inform wildlife management decisions related to bat use of abandoned mine sites, we used logistic regression, Akaike's information criterion, and multi-model inference to investigate hibernacula use by Townsend's big-eared bats using 9 years of data from surveys inside abandoned mines in southwestern Colorado. Townsend's big-eared bats were found in 38 of 133 mines surveyed (29%), and occupied mines averaged 2.6 individuals per mine. The model explaining the most variability in our data included number of openings and portal temperature at abandoned mines. In southwestern Colorado, we found that abandoned mine sites with more than one opening and portal temperatures near 08C were more likely to contain hibernating Townsend's big-eared bats. However, mines with only one opening and portal temperatures of !108C were occasionally occupied by Townsend's big-eared bat. Understanding mine use by Townsend's big-eared bat can help guide decisions regarding allocation of resources and placement of bat-compatible closures at mine sites scheduled for reclamation. When feasible we believe that surveys should be conducted inside all abandoned mines in a reclamation project at least once during winter prior to making closure and reclamation recommendations.

Research paper thumbnail of Occupancy of Random Plots by White-Tailed and Gunnison's Prairie Dogs

Journal of Wildlife Management, 2009

Research paper thumbnail of Observations on the Spotted Bat, Euderma maculatum, in Northwestern Colorado

Journal of Mammalogy, 1992

... We also sampled two sites at Echo Park, one at the confluence of the Green and Yamparivers on... more ... We also sampled two sites at Echo Park, one at the confluence of the Green and Yamparivers on a large sand-and-gravel bar, and another in and around the campground area. ... Colorado Division of Wildlife, 22 pp. GRFFmIN, DR 1971. ...

Research paper thumbnail of Irrigated Cornfields as Habitat for Small Mammals in the Sandsage Prairie Region of Western Kansas

Journal of Mammalogy, 1983

... The diminutive size of P. flavescens might have reduced trap success; thus, we probably under... more ... The diminutive size of P. flavescens might have reduced trap success; thus, we probably underestimated the size of the population. One snap-trapped P. flavescens had a partially eaten kernel of corn in its cheek pouch. Dipodomys ordii seems to be semiresident in cornfields. ...

Research paper thumbnail of Microclimate preferences during swarming and hibernation in the Townsend's big-eared bat, Corynorhinus townsendii

Journal of Mammalogy, 2010

ABSTRACT

Research paper thumbnail of A review of bat hibernacula across the western United States: Implications for white-nose syndrome surveillance and management

PLOS ONE

Efforts to conserve bats in the western United States have long been impeded by a lack of informa... more 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 bigeared 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

Research paper thumbnail of Intraspecific comparison of population structure, genetic diversity, and dispersal among three subspecies of Townsend’s big-eared bats, Corynorhinus townsendii townsendii, C. t. pallescens, and the endangered C. t. virginianus

Conservation Genetics, 2009

Townsend's big-eared bat, Corynorhinus townsendii, is distributed broadly across western North Am... more Townsend's big-eared bat, Corynorhinus townsendii, is distributed broadly across western North America and in two isolated, endangered populations in central and eastern United States. There are five subspecies of C. townsendii; C. t. pallescens, C. t. australis, C. t. townsendii, C. t. ingens, and C. t. virginianus with varying degrees of concern over the conservation status of each. The aim of this study was to use mitochondrial and microsatellite DNA data to examine genetic diversity, population differentiation, and dispersal of three C. townsendii subspecies. C. t. virginianus is found in isolated populations in the eastern United States and was listed as endangered under the Endangered Species Act in 1979. Concern also exists about declining populations of two western subspecies, C. t. pallescens and C. t. townsendii. Using a comparative approach, estimates of the genetic diversity within populations of the endangered subspecies, C. t. virginianus, were found to be significantly lower than within populations of the two western subspecies. Further, both classes of molecular markers revealed significant differentiation among regional populations of C. t. virginianus with most genetic diversity distributed among populations. Genetic diversity was not significantly different between C. t. townsendii and C. t. pallescens. Some populations of C. t. townsendii are not genetically differentiated from populations of C. t. pallescens in areas of sympatry. For the western subspecies gene flow appears to occur primarily through male dispersal. Finally, geographic regions representing significantly differentiated and genetically unique populations of C. townsendii virginianus are recognized as distinct evolutionary significant units.

Research paper thumbnail of Intraspecific comparison of population structure, genetic diversity, and dispersal among three subspecies of Townsend’s big-eared bats, Corynorhinus townsendii townsendii, C. t. pallescens, and the endangered C. t. virginianus

Conservation Genetics, 2008

Research paper thumbnail of Small Mammals of Winter Wheat and Grain Sorghum Croplands in West-Central Kansas

Research paper thumbnail of Colorado bat conservation plan

construction, water impoundments, blast ing of cl iffs for avalanche comrol) that impact cliff fa... more construction, water impoundments, blast ing of cl iffs for avalanche comrol) that impact cliff faces or rock outcrops. V. GAPS rN KNOWLEDGE: Litt le or no information known 011 popu lation treads, winter roosting requirements, winter range, importance of snags as summer roosts, and use and acceptance of bat gates. More information is a.lso needed on foraging requirements.

Research paper thumbnail of Observations of swarming by bats and band recoveries in Colorado

Research paper thumbnail of Examination of Fungal Diversity Present on Mexican Free-Tailed Bats, Tadarida Brasiliensis Mexicana, in Colorado

The Southwestern Naturalist

Research paper thumbnail of Silver-Haired Bats Associated with Abandoned Mines in Colorado Provide Insights Into Winter Habitat and Roost Use

Western North American Naturalist

Research paper thumbnail of Guidelines for Defining Biologically Important Bat Roosts: A Case Study from Colorado

Journal of Fish and Wildlife Management, 2017

Conservation of roosts is regularly recommended as a strategy to decrease the risk of threats to ... more Conservation of roosts is regularly recommended as a strategy to decrease the risk of threats to local bat populations (e.g., white-nose syndrome). Determining whether a roost site plays a meaningful role in maintaining a local bat population can be difficult given the variability found in roost structure type, and use by season, duration, and sex. Here we provide land managers and biologists with guidelines to aid in the decision process for determining which roosts are biologically important in maintaining healthy bat populations at a local scale. We define methods for determining biologically important roost sites and provide a case study of their use on bat roosts in Colorado. To be considered biologically important, we suggest that a roost meet two primary criteria: 1) it is considered a hibernaculum, maternity roost, transient roost, colonial bachelor roost, or fall swarming site used by bat species that are gregarious roosters, hibernators, or are known to swarm, and 2) if th...

Research paper thumbnail of Small Mammals of Winter Wheat and Grain Sorghum Croplands in West-Central Kansas

Research paper thumbnail of Allen's Big-Eared Bat (Idionycteris phyllotis) Documented in Colorado Based on Recordings of its Distinctive Echolocation Call

The Southwestern Naturalist, 2009

Allen's big-eared bat (Idionycteris phyllotis) inhabits much of the southwestern USA, but has not... more Allen's big-eared bat (Idionycteris phyllotis) inhabits much of the southwestern USA, but has not been documented in Colorado. We recorded echolocation calls consistent with I. phyllotis near La Sal Creek, Montrose County, Colorado. Based on characteristics of echolocation calls and flight behavior, we conclude that the echolocation calls described here were emitted by I. phyllotis and that they represent the first documentation of this species in Colorado.

Research paper thumbnail of Distribution of the Big Free-Tailed Bat (Nyctinomops macrotis) in Colorado

The Southwestern Naturalist, 2001

... Thanks to CA Jones and the Denver Muse-um of Nature and Science for assistance with speci-men... more ... Thanks to CA Jones and the Denver Muse-um of Nature and Science for assistance with speci-mens, J. Pape for providing Department of Public Health and Environment records, and KM Canes-torp and T. Laurion for providing the juvenile spec-imen. ...

Research paper thumbnail of Hibernacula selection by Townsend's big-Eared bat in southwestern Colorado

The Journal of Wildlife Management, 2011

In western United States, both mine reclamations and renewed mining at previously abandoned mines... more In western United States, both mine reclamations and renewed mining at previously abandoned mines have increased substantially in the last decade. This increased activity may adversely impact bats that use these mines for roosting. Townsend's big-eared bat (Corynorhinus townsendii) is a species of conservation concern that may be impacted by ongoing mine reclamation and renewed mineral extraction. To help inform wildlife management decisions related to bat use of abandoned mine sites, we used logistic regression, Akaike's information criterion, and multi-model inference to investigate hibernacula use by Townsend's big-eared bats using 9 years of data from surveys inside abandoned mines in southwestern Colorado. Townsend's big-eared bats were found in 38 of 133 mines surveyed (29%), and occupied mines averaged 2.6 individuals per mine. The model explaining the most variability in our data included number of openings and portal temperature at abandoned mines. In southwestern Colorado, we found that abandoned mine sites with more than one opening and portal temperatures near 08C were more likely to contain hibernating Townsend's big-eared bats. However, mines with only one opening and portal temperatures of !108C were occasionally occupied by Townsend's big-eared bat. Understanding mine use by Townsend's big-eared bat can help guide decisions regarding allocation of resources and placement of bat-compatible closures at mine sites scheduled for reclamation. When feasible we believe that surveys should be conducted inside all abandoned mines in a reclamation project at least once during winter prior to making closure and reclamation recommendations.

Research paper thumbnail of Occupancy of Random Plots by White-Tailed and Gunnison's Prairie Dogs

Journal of Wildlife Management, 2009

Research paper thumbnail of Observations on the Spotted Bat, Euderma maculatum, in Northwestern Colorado

Journal of Mammalogy, 1992

... We also sampled two sites at Echo Park, one at the confluence of the Green and Yamparivers on... more ... We also sampled two sites at Echo Park, one at the confluence of the Green and Yamparivers on a large sand-and-gravel bar, and another in and around the campground area. ... Colorado Division of Wildlife, 22 pp. GRFFmIN, DR 1971. ...

Research paper thumbnail of Irrigated Cornfields as Habitat for Small Mammals in the Sandsage Prairie Region of Western Kansas

Journal of Mammalogy, 1983

... The diminutive size of P. flavescens might have reduced trap success; thus, we probably under... more ... The diminutive size of P. flavescens might have reduced trap success; thus, we probably underestimated the size of the population. One snap-trapped P. flavescens had a partially eaten kernel of corn in its cheek pouch. Dipodomys ordii seems to be semiresident in cornfields. ...

Research paper thumbnail of Microclimate preferences during swarming and hibernation in the Townsend's big-eared bat, Corynorhinus townsendii

Journal of Mammalogy, 2010

ABSTRACT

Research paper thumbnail of A review of bat hibernacula across the western United States: Implications for white-nose syndrome surveillance and management

PLOS ONE

Efforts to conserve bats in the western United States have long been impeded by a lack of informa... more 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 bigeared 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

Research paper thumbnail of Intraspecific comparison of population structure, genetic diversity, and dispersal among three subspecies of Townsend’s big-eared bats, Corynorhinus townsendii townsendii, C. t. pallescens, and the endangered C. t. virginianus

Conservation Genetics, 2009

Townsend's big-eared bat, Corynorhinus townsendii, is distributed broadly across western North Am... more Townsend's big-eared bat, Corynorhinus townsendii, is distributed broadly across western North America and in two isolated, endangered populations in central and eastern United States. There are five subspecies of C. townsendii; C. t. pallescens, C. t. australis, C. t. townsendii, C. t. ingens, and C. t. virginianus with varying degrees of concern over the conservation status of each. The aim of this study was to use mitochondrial and microsatellite DNA data to examine genetic diversity, population differentiation, and dispersal of three C. townsendii subspecies. C. t. virginianus is found in isolated populations in the eastern United States and was listed as endangered under the Endangered Species Act in 1979. Concern also exists about declining populations of two western subspecies, C. t. pallescens and C. t. townsendii. Using a comparative approach, estimates of the genetic diversity within populations of the endangered subspecies, C. t. virginianus, were found to be significantly lower than within populations of the two western subspecies. Further, both classes of molecular markers revealed significant differentiation among regional populations of C. t. virginianus with most genetic diversity distributed among populations. Genetic diversity was not significantly different between C. t. townsendii and C. t. pallescens. Some populations of C. t. townsendii are not genetically differentiated from populations of C. t. pallescens in areas of sympatry. For the western subspecies gene flow appears to occur primarily through male dispersal. Finally, geographic regions representing significantly differentiated and genetically unique populations of C. townsendii virginianus are recognized as distinct evolutionary significant units.