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A Simple Method For Restraint Of Small Mammals For Sampling Blood Or Tissue In The Field, John L. Orrock
A Simple Method For Restraint Of Small Mammals For Sampling Blood Or Tissue In The Field, John L. Orrock
Western North American Naturalist
Because wild rodents often harbor zoonotic pathogens that can be transmitted via saliva, urine, or feces (e.g., hantaviruses), researchers can be at risk when collecting rodent blood or tissue samples that are required for innumerable assays (e.g., infection status, hormone assays, etc.). I describe how inexpensive, readily available 50-mL centrifuge tubes can be easily modified to create a handling tube for the safe restraint of small rodents while a blood and/or tissue sample is collected from the tail. This approach has been used to successfully sample thousands of deer mice (Peromyscus maniculatus), the primary host for Sin Nombre …
Estimating Abundance Of Desert Mule Deer Using Fecal Dna–Based Capture-Recapture, Stephen S. Pfeiler, Mary M. Conner, Jane S. Mckeever, Rachel S. Crowhurst, Clinton W. Epps, Gerald P. Mulcahy, Erin P. Meredith, Thomas R. Stephenson
Estimating Abundance Of Desert Mule Deer Using Fecal Dna–Based Capture-Recapture, Stephen S. Pfeiler, Mary M. Conner, Jane S. Mckeever, Rachel S. Crowhurst, Clinton W. Epps, Gerald P. Mulcahy, Erin P. Meredith, Thomas R. Stephenson
Western North American Naturalist
Wildlife conservationists and managers often need to estimate abundance and demographic parameters to monitor the status of populations, and to ensure that these populations are meeting management goals. DNA capture-recapture surveys have become increasingly common in situations where physical surveys are consistently difficult or counts are small or variable. Desert mule deer (Odocoileus hemionus eremicus) inhabit rugged terrain, occur at low population densities, and demonstrate cryptic behaviors, making monitoring and assessing population status difficult. We assessed the effectiveness of a fecal DNA–based capture-recapture method for estimating abundance and survival of desert mule deer. We designed and implemented a …
Self-Compatibility In Lomatium Dissectum (Apiaceae) And The Diverse Andrena Bees That Dominate Regional Lomatium Pollinator Faunas, James H. Cane, Melissa Weber, Byron G. Love
Self-Compatibility In Lomatium Dissectum (Apiaceae) And The Diverse Andrena Bees That Dominate Regional Lomatium Pollinator Faunas, James H. Cane, Melissa Weber, Byron G. Love
Western North American Naturalist
Species of biscuitroot (Lomatium: Apiaceae) are endemic to western North America, where multiple species can be common members of perennial wildflower communities from basin sagebrush-steppe and juniper woodlands up to alpine meadows. Despite Lomatium being the largest genus of Apiaceae in North America, little is known about its pollination needs or pollinators. Manual pollinations of the tiny flowers of one species, desert parsley (L. dissectum), showed it to be a self-compatible species, akin to other genera of Apiaceae. Seed production, however, largely requires pollinators to move pollen within and between the andromonoecious umbels. Regional sampling …
Activity And Thermal Biology Of Blunt-Nosed Leopard Lizards (Gambelia Sila) In The San Joaquin Desert Of California, David J. Germano
Activity And Thermal Biology Of Blunt-Nosed Leopard Lizards (Gambelia Sila) In The San Joaquin Desert Of California, David J. Germano
Western North American Naturalist
Because lizards are ectotherms, their life-history traits are greatly influenced by variations in thermal regimes. The Blunt-nosed Leopard Lizard (Gambelia sila) is an endangered lizard that dominates the lizard community in the San Joaquin Desert. Because of the protected status of the species, census protocols are in place to ensure that censuses are conducted during optimal times for lizard activity, but the protocols have not been evaluated by a detailed study. Also, because of changing thermal regimes as a result of climate change, there is concern for lizard species worldwide. I studied the activity and thermal biology of …
Prehistoric Shellfish Utilization And Settlement Systems On Western Santa Cruz Island, Michael A. Glassow
Prehistoric Shellfish Utilization And Settlement Systems On Western Santa Cruz Island, Michael A. Glassow
Western North American Naturalist
Archaeologists generally have not taken advantage of the distinctive characteristics of assemblages of shellfish remains from prehistoric sites to gain information about movement of people between sites within their territory. I attempt to demonstrate this potential through analysis of shell assemblages obtained through small-scale test excavation at 2 archaeological sites in the interior of Santa Cruz Island: CA-SCRI-796 in the western sector of the island and CA-SCRI-758 at an upland location in the central sector. An aspect of the data analysis focused on strata containing an abundance of red abalone shells, dating sometime between 3700 and 3350 cal BC at …
Limitations In The Reproductive Success Of A Burrow-Nesting Bird (Momotus Mexicanus) During A Humid Season, Grégory Michaël Charre, Omar Paniagua, Marcela Osorio-Beristain
Limitations In The Reproductive Success Of A Burrow-Nesting Bird (Momotus Mexicanus) During A Humid Season, Grégory Michaël Charre, Omar Paniagua, Marcela Osorio-Beristain
Western North American Naturalist
Burrow-nesting birds are limited by access to nest sites, particularly in years of very high humidity levels, such those seen with El Niño, or in forests that are fragmented due to the effects of human activity. We assessed the breeding success of Momotus mexicanus nesting along the earth bank of a secondary road corridor in a seasonally dry tropical forest in Central Mexico. We monitored 28 nests during the reproductive period and characterized the composition of the soil where they were constructed, as well as other physical variables. One nest produced 2 fledglings, and the other 27 failed to …
Tolerance To Disturbance Regulated By Attractiveness Of Resources: A Case Study Of Desert Bighorn Sheep Within The River Mountains, Nevada, Christopher Lowrey, Kathleen M. Longshore
Tolerance To Disturbance Regulated By Attractiveness Of Resources: A Case Study Of Desert Bighorn Sheep Within The River Mountains, Nevada, Christopher Lowrey, Kathleen M. Longshore
Western North American Naturalist
Human activity may mimic predation risks for wildlife by causing abandonment of foraging sites and increasing expenditure of energy. Animals that can tolerate nonlethal disturbance may minimize these fitness costs. We examine this aspect of the risk–disturbance hypothesis by first analyzing recent habitat use of desert bighorn sheep relative to areas of attraction and disturbance. We then compare and contrast sheep responses to differing levels of anthropogenic disturbance between 2 time periods, 30 years apart. Desert bighorn sheep were tolerant of suburban activity when a consistent forage resource (municipal grass) was provided. Males were more tolerant than females, and females …
Daily And Monthly Activity Of Brown Bears (Ursus Arctos) Near A Proposed Industrial Project In Coastal British Columbia, Matthew L. Richardson
Daily And Monthly Activity Of Brown Bears (Ursus Arctos) Near A Proposed Industrial Project In Coastal British Columbia, Matthew L. Richardson
Western North American Naturalist
The Kitimat Liquefied Natural Gas (KLNG) Plant is proposed for construction adjacent to Bish Creek (Kitimat, British Columbia, Canada). Bish Creek is a corridor for brown bears (Ursus arctos), and 8 camera traps were deployed along the creek for 1442 trapping days in 2014 to determine baseline activity of brown bears. Brown bear activity varied across weeks, peaking particularly in July and September. Within a 24-h day, bears were commonly photographed during hours 5, 6, and 21 and uncommonly photographed during the 3 hours preceding noon and a 4-h period in the afternoon. However, the time of day …
Diet Of The Mohave Ground Squirrel (Xerospermophilus Mohavensis) In Relation To Season And Rainfall, Barbara M. Leitner, Philip Leitner
Diet Of The Mohave Ground Squirrel (Xerospermophilus Mohavensis) In Relation To Season And Rainfall, Barbara M. Leitner, Philip Leitner
Western North American Naturalist
The Mohave ground squirrel (Xerospermophilus mohavensis) is endemic to the western Mojave Desert of California. It is listed as threatened under the California Endangered Species Act, yet there is little published information on its habitat requirements. We studied the diet of Mohave ground squirrels at 4 sites in desert scrub habitat in Inyo County, California, primarily by microhistological analysis of 754 samples of fecal pellets collected from live-trapped animals. Over all sites and seasons, shrub foliage was the largest component of the diet (39.8% relative density) and mainly derived from several taxa of Chenopodiaceae: winterfat (Krascheninnikovia lanata …
Fine-Scale Genetic Structure In Female Mule Deer (Odocoileus Hemionus), Cortney W. Noble, Jeremy M. Bono, Helen K. Pigage, David W. Hale, Jon C. Pigage
Fine-Scale Genetic Structure In Female Mule Deer (Odocoileus Hemionus), Cortney W. Noble, Jeremy M. Bono, Helen K. Pigage, David W. Hale, Jon C. Pigage
Western North American Naturalist
Fine-scale genetic structure in animal populations can have important consequences for evolutionary processes and can influence conservation and management decisions. Cervids often live in matrilineal social groups, and this spatial grouping can create fine-scale genetic structure among females. We used DNA and radio-location data at Fort Carson Military Reservation in south central Colorado, USA, to determine whether female mule deer (Odocoileus hemionus) living in close proximity were more likely to be related. Spatial data were obtained over an 18-month period using data transmitted from GPS collars. Average positions for each animal were correlated with relatedness estimates calculated using …
Facing A Changing World: Thermal Physiology Of American Pikas (Ochotona Princeps), Hans W. Otto, James A. Wilson, Erik A. Beever
Facing A Changing World: Thermal Physiology Of American Pikas (Ochotona Princeps), Hans W. Otto, James A. Wilson, Erik A. Beever
Western North American Naturalist
American pikas (Ochotona princeps) are of concern with respect to warming montane temperatures; however, little information exists regarding their physiological ability to adapt to warming temperatures. Previous studies have shown that pikas have high metabolism and low thermal conductance, which allow survival during cold winters. It has been hypothesized that these characteristics may be detrimental, given the recent warming trends observed in montane ecosystems. We examined resting metabolic rate, surface activity, and den and ambient temperatures (Ta) of pikas in late summer (August 2011 and 2012) at 2 locations in the Rocky Mountains. Resting metabolic rate was calculated …
Use Of External Characteristics For Rapid Identification Of Gender Of Pocket Gophers, Roger A. Baldwin, Ryan Meinerz
Use Of External Characteristics For Rapid Identification Of Gender Of Pocket Gophers, Roger A. Baldwin, Ryan Meinerz
Western North American Naturalist
Pocket gophers are of great importance both for their function in ecological systems and for their impact on anthropogenic environments. Managing pocket gopher populations requires a fundamental understanding of population demographics, specifically sex ratios; yet quick and reliable techniques for visually identifying gender of pocket gophers are lacking. We developed a visual identification method based on external characteristics of genitalia and mammae that allows for rapid, yet correct assessment of gender in pocket gophers. This approach was particularly accurate (>99%) for visual identifications in the field. Our approach was also accurate (>98%) for frozen specimens, although care must …
Tree Mortality In Mature Riparian Forest: Implications For Fremont Cottonwood Conservation In The American Southwest, Douglas C. Andersen
Tree Mortality In Mature Riparian Forest: Implications For Fremont Cottonwood Conservation In The American Southwest, Douglas C. Andersen
Western North American Naturalist
Mature tree mortality rates are poorly documented in desert riparian woodlands. I monitored deaths and calculated annual survivorship probability (PS) in 2 groups of large (27–114 cm DBH), old (≥40 years old) Fremont cottonwood (Populus fremontiiWats.) in a stand along the free-flowing Yampa River in semiarid northwestern Colorado. PS = 0.993 year–1 in a group (n = 126) monitored over 2003–2013, whereas PS = 0.985 year–1 in a group (n = 179) monitored over the same period plus 3 earlier years (2000–2003) that included drought and a defoliating insect outbreak. …
Late-Season Survey Of Bumble Bees Along Canadian Highways Of British Columbia And Yukon Territories, Timothy D. Hatten, James P. Strange, Jill M. Maxwell
Late-Season Survey Of Bumble Bees Along Canadian Highways Of British Columbia And Yukon Territories, Timothy D. Hatten, James P. Strange, Jill M. Maxwell
Western North American Naturalist
Bumble bees are important pollinators of flowering plants, foraging and providing pollination services throughout the growing season. They are adapted to cool temperatures and are among the most important of all pollinators at high elevations and northern latitudes. Over the past several decades, multiple species of bumble bees have experienced declines in both geographic range and abundance in Europe and North America, while 4 species of the genus Bombus (Bombus) have suffered dramatic declines in the United States. Such declines are not as evident in Alaska, and the status of Bombus remains relatively unknown in the adjacent territories …
Estimating Bighorn Sheep (Ovis Canadensis) Abundance Using Noninvasive Sampling At A Mineral Lick Within A National Park Wilderness Area, Kathryn A. Schoenecker, Mary Kay Watry, Laura E. Ellison, Michael K. Schwartz, Gordon Luikart
Estimating Bighorn Sheep (Ovis Canadensis) Abundance Using Noninvasive Sampling At A Mineral Lick Within A National Park Wilderness Area, Kathryn A. Schoenecker, Mary Kay Watry, Laura E. Ellison, Michael K. Schwartz, Gordon Luikart
Western North American Naturalist
Conservation of species requires accurate population estimates. We used genetic markers from feces to determine bighorn sheep abundance for a herd that was hypothesized to be declining and in need of population status monitoring. We sampled from a small but accessible portion of the population’s range where animals naturally congregate at a natural mineral lick to test whether we could accurately estimate population size by sampling from an area where animals concentrate. We used mark-recapture analysis to derive population estimates, and compared estimates from this smaller spatial sampling to estimates from sampling of the entire bighorn sheep range. We found …
Population Characteristics Of Big-Brown Bat And Arizona Myotis Using Artificial Roosting Structures In Northern Arizona, Joel M. Diamond, R. Nathan Gwinn, Janet Johnson, Hannah Telle, Gabrielle F. Diamond
Population Characteristics Of Big-Brown Bat And Arizona Myotis Using Artificial Roosting Structures In Northern Arizona, Joel M. Diamond, R. Nathan Gwinn, Janet Johnson, Hannah Telle, Gabrielle F. Diamond
Western North American Naturalist
Big brown bats (Eptesicus fuscus) and a close relative of Arizona myotis (Myotis occultus), the little brown bat (Myotis lucifugus) in the eastern United States, are among those species experiencing unprecedented population declines related to white-nose syndrome (WNS). Determining population characteristic baselines for big brown bat and Arizona myotis is paramount in detecting population declines before they reach critical levels. We targeted 2 bat species strongly associated with ponderosa pine forests in northern Arizona. Big brown bats and Arizona myotis readily utilize human-made structures and have a cosmopolitan distribution across the ponderosa pine ( …
Population Genetic Structure Of The Baird's Pocket Gopher, Geomys Breviceps, In Eastern Texas, Sarah R. Welborn, Jessica E. Light
Population Genetic Structure Of The Baird's Pocket Gopher, Geomys Breviceps, In Eastern Texas, Sarah R. Welborn, Jessica E. Light
Western North American Naturalist
The Baird’s pocket gopher (Geomys breviceps) is a solitary, fossorial rodent found throughout areas of Texas, Arkansas, Oklahoma, and Louisiana. These rodents are highly modified morphologically for an underground lifestyle, often resulting in limited vagility and isolated populations. Despite these unique characteristics, little is known about the population genetics of pocket gophers. We used mitochondrial and microsatellite data and performed a series of population genetic analyses to better understand the population structure and gene flow among a series of G. brevicepslocalities. Population genetic analyses supported high levels of gene flow among nearby localities (within 2 km of …
Home-Range Size And Subadult Dispersal Of Black Bears In The Cascade Range Of Western Oregon, Dave Immell, Dewaine H. Jackson, Margaret C. Boulay
Home-Range Size And Subadult Dispersal Of Black Bears In The Cascade Range Of Western Oregon, Dave Immell, Dewaine H. Jackson, Margaret C. Boulay
Western North American Naturalist
Knowledge of home range size and subadult dispersal activity of North American black bears is essential for understanding the complexity of how bears interact within populations and the environment. During 1993-98, we monitored 96 radiocollared black bears (Ursus americanus) in the Cascade Range of western Oregon to estimate home range and dispersal movements. Composite fixed-kernel home ranges were calculated for 37 bears. Mean home range size differed between sexes (189.7 km2 for males and 33.6 km2 for females); however, there was no difference between subadult and adult male or subadult and adult female mean home range …
Diet Of The Exotic American Bullfrog, Lithobates Catesbeianus, In A Stream Of Northwestern Baja California, Mexico, Liliana Ortíz-Serrato, Gorgonio Ruiz-Campos, Jorge H. Valdez-Villavicencio
Diet Of The Exotic American Bullfrog, Lithobates Catesbeianus, In A Stream Of Northwestern Baja California, Mexico, Liliana Ortíz-Serrato, Gorgonio Ruiz-Campos, Jorge H. Valdez-Villavicencio
Western North American Naturalist
We studied the diet of the exotic American bullfrog (Lithobates catesbeianus) in Arroyo San Carlos, located in northwestern Baja California, Mexico, during spring and summer 2009. Analysis of 64 stomach contents revealed 15 prey types, of which the exotic red crayfish (Procambarus clarkii) and terrestrial isopods (Armadillidiidae) were the most significant items (according to an index of their relative importance), making up 64% and 31% of the bullfrog’s diet, respectively. Diet differed between the sexes, with red crayfish eaten more frequently by males (84%) than females (69%). Bullfrog diet changed with body size, with smaller individuals …
Bison Selection Of Prairie Dog Colonies On Shortgrass Steppe, Jennifer G. Chipault, James K. Detling
Bison Selection Of Prairie Dog Colonies On Shortgrass Steppe, Jennifer G. Chipault, James K. Detling
Western North American Naturalist
American bison (Bison bison L.) preferentially use black-tailed prairie dog (Cynomys ludovicianus L.) colonies over uncolonized range in the mixed-grass prairie of North America. To assess bison use of prairie dog colonies in a different ecosystem, the shortgrass steppe, this study was conducted at the Vermejo Park Ranch, New Mexico. Driving surveys were conducted in summer 2007 to determine the number of bison on and off prairie dog colonies in 2 pastures. Prairie dogs occupied 25.5% and 48.5% of the 2 pastures surveyed. Bison of both sexes used prairie dog colonies more than expected compared to a scenario …
Seasonal Variation In Offspring Sex Ratio In The Snowy Plover, Sarah T. Saalfeld, Warren C. Conway, David A. Haukos, William P. Johnson
Seasonal Variation In Offspring Sex Ratio In The Snowy Plover, Sarah T. Saalfeld, Warren C. Conway, David A. Haukos, William P. Johnson
Western North American Naturalist
The Snowy Plover (Charadrius nivosus) is unique in being a determinate layer of an odd modal clutch size and in having a variable mating system in which female brood desertion occurs regularly. These traits make determining Snowy Plover offspring sex ratios important not only for long-term population stability, as the species is of conservation concern, but also for application to sex allocation theory. In this study, we determined Snowy Plover offspring sex ratios, examined differential costs of producing male and female offspring, and evaluated sex ratio variation in relation to maternal condition, habitat condition, and time during the …
Jeffrey Pine Seed Dispersal In The Sierra San Pedro Mártir, Baja California, Mexico, Stephen B. Vander Wall, Mark S. Enders, Sarah Barga, Christopher Moore, Amy Seaman, Ramón Perea
Jeffrey Pine Seed Dispersal In The Sierra San Pedro Mártir, Baja California, Mexico, Stephen B. Vander Wall, Mark S. Enders, Sarah Barga, Christopher Moore, Amy Seaman, Ramón Perea
Western North American Naturalist
The Sierra San Pedro Mártir (SSPM) in northern Baja California, Mexico, is a remote mountain at the southern edge of the California Floristic Province, a vegetation type that includes the Sierra Nevada of California and western Nevada. Unlike most forests in the southwestern United States, the forests of the SSPM have never been logged and have experienced only light grazing in recent years, and wildfires have not been suppressed until recent decades. The SSPM represents one of the best examples of an intact presettlement forest in the California Floristic Province. We investigated the mode of seed dispersal of Jeffrey pine …
Ringtail (Bassariscus Astutus) Ecology And Behavior In Central New Mexico, Usa, Robert L. Harrison
Ringtail (Bassariscus Astutus) Ecology And Behavior In Central New Mexico, Usa, Robert L. Harrison
Western North American Naturalist
I studied the ecology and behavior of ringtails (Bassariscus astutus) in juniper (Juniperus monosperma) woodland on the Sevilleta National Wildlife Refuge in central New Mexico. Average home-range sizes of ringtails (males 462 ha, females 94 ha, 95% fixed kernel) were among the largest reported to date. Females moved least in summer and most in autumn, but males showed no seasonal trend in movements. The average stay in a single den was 1.3 days. I found no effect of the closeness of approach of the den observer on the distance moved between successive dens. Ringtails used a …
Black-Footed Ferret Home Ranges In Conata Basin, South Dakota, Travis M. Livieri, Eric M. Anderson
Black-Footed Ferret Home Ranges In Conata Basin, South Dakota, Travis M. Livieri, Eric M. Anderson
Western North American Naturalist
We estimated annual home ranges and core areas of black-footed ferrets (Mustela nigripes) in Conata Basin, South Dakota, by collecting 834 locations of 28 ferrets (20 females, 8 males) through spotlighting from October 1997 to September 2000. Area-per-observation curves showed that a minimum of 23 locations were needed to estimate fixed-kernel home-range size. Mean 95% and 50% fixed-kernel annual home-range sizes of females (95%: 64.7 ha, SE = 11.6; 50%: 12.7 ha, SE = 3.0) were significantly smaller and less variable than those of males (95%: 131.8 ha, SE = 40.3; 50%: 35.6 ha, SE = 16.5). Minimum …
Activity Patterns Of Black Bears In Relation To Sex, Season, And Daily Movement Rates, Jesse S. Lewis, Janet L. Rachlow
Activity Patterns Of Black Bears In Relation To Sex, Season, And Daily Movement Rates, Jesse S. Lewis, Janet L. Rachlow
Western North American Naturalist
Activity patterns of animals can vary depending on both endogenous and environmental factors. Although black bears exhibit substantial variation in activity across the year, relatively little is known about how daily activity patterns and associated movement rates differ among sex and age classes across seasons. We used fine-scale movement data from black bears fitted with GPS collars to evaluate movement and activity patterns across sex and age classes for daily and seasonal time periods in relation to mating and foraging behavior. Black bears were most active during crepuscular time periods, moderately active during the day, and least active at night, …
Differential Phytosociological Interactions Involving Male And Female Atriplex Bonnevillensis, Jordan Sinclair, John M. Emlen, Matthew Rinella, Jessica Snelgrove, D. Carl Freeman
Differential Phytosociological Interactions Involving Male And Female Atriplex Bonnevillensis, Jordan Sinclair, John M. Emlen, Matthew Rinella, Jessica Snelgrove, D. Carl Freeman
Western North American Naturalist
Wind-pollinated dioecious plants often exhibit spatial segregation of the sexes. This partial niche separation has most often been explored using abiotic niche axes. However, if the sexes are truly separated in space, then they are apt to encounter different plant species that may heavily affect growth and reproduction. Also, to the extent that their niches differ, the sexes may respond differently to the same co-occurring species. Here we examine interspecific interactions that influence male and female reproductive potential in Atriplex bonnevillensis. Using Emlen's interaction assessment, a technique which assesses species interactions based on cover classes, we show that Salsola species …
Planted Grasslands And Native Sod Prairie: Equivalent Habitat For Grassland Birds?, Kristel K. Bakker, Kenneth F. Higgins
Planted Grasslands And Native Sod Prairie: Equivalent Habitat For Grassland Birds?, Kristel K. Bakker, Kenneth F. Higgins
Western North American Naturalist
Little is known about how avian relationships to tracts of native sod prairie compare with avian relationships to single and multiple species of cool- and warm-season grassland plantings. We compared grassland bird species richness and density in 5 grassland cover types (n = 97) in the tallgrass prairie region of eastern South Dakota and western Minnesota, 2001–2004. Grassland bird species richness was significantly higher in native sod prairies than it was in all planted cover types except warm-season mixes. Grasslands dominated by exotic species did not support as many grassland bird species or have species densities as high as …
Diet Of The Mogollon Vole As Indicated By Stable-Isotope Analysis (Δ13C And Δ15N), Carol L. Chambers, Richard R. Doucett
Diet Of The Mogollon Vole As Indicated By Stable-Isotope Analysis (Δ13C And Δ15N), Carol L. Chambers, Richard R. Doucett
Western North American Naturalist
There are no published studies on the diet of Mogollon voles (Microtus mogollonensis) although this species occurs throughout the Southwest in montane forestlands. Mogollon voles are believed to be herbivorous, selecting the vegetative portion of grass as their dominant food source. Herbivores frequently select more easily digested C3 plants over C4 plants; we thus expected Mogollon voles would feed primarily on C3 plants. We collected hair samples from Mogollon voles captured in northern Arizona between 1967 and 2003 and plant samples from some capture sites. Then we compared stable carbon (δ13C) and nitrogen …
Seasonality And Fidelity In Roost Use Of The Mexican Free-Tailed Bat, Tadarida Brasiliensis, In An Urban Setting, Jeffrey A. Scales, Kenneth T. Wilkins
Seasonality And Fidelity In Roost Use Of The Mexican Free-Tailed Bat, Tadarida Brasiliensis, In An Urban Setting, Jeffrey A. Scales, Kenneth T. Wilkins
Western North American Naturalist
We studied 7 urban roosts occupied by Mexican free-tailed bats (Tadarida brasiliensis) in downtown Waco, Texas, from August 2001 to September 2002. We examined frequency of roost use, colony sizes, and roost fidelity in relation to gender. Use of roosts and colony sizes were highest in the fall and lowest in the winter, but fluctuated widely during the study. These roosts were not used by maternity colonies, and patterns of occupancy suggested that they served as stopover sites during migratory seasons. Individual bats exhibited high fidelity to discrete roosts included in the study. However, the bats commonly left …