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Ungulates commonly select habitat with higher forage biomass and or nutritional quality to improve body condition and fitness. However, predation risk can alter ungulate habitat selection and foraging behavior and may affect their nutritional condition. Ungulates often choose areas with lower predation risk, sometimes sacrificing higher quality forage. This forage-predation risk trade-off can be important for life history strategies and influences individual nutritional condition and population vital rates. We used GPS collar data from adult female mule deer (Odocoileus hemionus) and mountain lions (Puma concolor) to model mule deer habitat selection in relation to forage conditions, stalking cover and predation risk from mountain lions to determine if a forage-predation risk trade-off existed for mule deer in central New Mexico. We also examined mountain lion kill sites and mule deer foraging locations to assess trade-offs at a finer scale. Forage biomass and protein content were inversely correlated with horizontal visibility, hence associated with higher stalking cover for mountain lions, suggesting a forage-predation risk trade-off for mule deer. Mule deer habitat selection was influenced by forage biomass and protein content at the landscape and within home range spatial scales, with forage protein being related to habitat selection during spring and summer and forage biomass during winter. However, mule deer selection for areas with better foraging conditions was constrained by landscape-scale encounter risk for mountain lions, such that increasing encounter risk was associated with diminished selection for areas with better foraging conditions. Mule deer also selected for areas with higher visibility when mountain lion predation risk was higher. Mountain lion kill sites were best explained by decreasing horizontal visibility and available forage protein, suggesting that deer may be selecting for forage quality at the cost of predation risk. A site was 1.5 timesmore likely to be a kill site with each 1-meter decrease in visibility (i.e., increased stalking cover). Mule deer selection of foraging sites was related to increased forage biomass, further supporting the potential for a trade-off scenario. Mule deer utilized spatio-temporal strategies and risk-conditional behavior to reduce predation risk, and at times selected suboptimal foraging areas with lower predation risk. [ABSTRACT FROM AUTHOR]

Wildlife diseases have implications for ecology, conservation, human health, and health of domestic animals. They may impact wildlife health and population dynamics. Exposure rates of coyotes (Canis latrans) to pathogens such as Yersinia pestis, the cause of plague, may reflect prevalence rates in both rodent prey and human populations. We captured coyotes in north-central New Mexico during 2005–2008 and collected blood samples for serologic surveys. We tested for antibodies against canine distemper virus (CDV, Canine morbillivirus), canine parvovirus (CPV, Carnivore protoparvovirus), plague, tularemia (Francisella tularensis), and for canine heartworm (Dirofilaria immitis) antigen. Serum biochemistry variables that fell outside reference ranges were probably related to capture stress. We detected antibodies to parvovirus in 32/32 samples (100%), and to Y. pestis in 26/31 (84%). More than half 19/32 (59%) had antibodies against CDV, and 5/31 (39%) had antibodies against F. tularensis. We did not detect any heartworm antigens (n ¼ 9). Pathogen prevalence was similar between sexes and among the three coyote packs in the study area. Parvovirus exposure appeared to happen early in life, and prevalence of antibodies against CDV increased with increasing age class. Exposure to Y. pestis and F. tularensis occurred across all age classes. The high coyote seroprevalence rates observed for CPV, Y. pestis, and CDV may indicate high prevalence in sympatric vertebrate populations, with implications for regional wildlife conservation as well as risk to humans via zoonotic transmission. [ABSTRACT FROM AUTHOR]

There is little information about nesting ecology of the federally endangered Black-capped Vireo (Vireo atricapilla) in the southern and western region of its breeding range, which is characterized by xeric thornscrub and patchy low-growing vegetation. We mapped territories and monitored 119 Black-capped Vireo nests across seven study sites in 2009 and 2010 in Val Verde County, Texas in the Devil's River region on the western edge of the Edwards Plateau. We observed 69 nests with cameras to identify nest predators. Clutch size was significantly smaller in 2009 (3.4 ± 0.82) than in 2010 (3.8 ± 0.43). Both nest depredation and parasitism by Brown-headed Cowbirds (Molothrus ater) were > 10% higher in 2009 than in 2010. There was a large diversity of nest predators identified including Brown-headed Cowbird (n = 4), snakes (n = 4), and Greater Roadrunner (Geococcyx californianus) (n = 3). Species identified that have not been previously observed as Black-capped Vireo nest predators were bobcat (Lynx rufus), common raccoon (Procyon lotor), Greater Roadrunner, and the greater arid-land katydid (Neobarrettia spinosa). Productivity of Black-capped Vireos in the Devil's River area appeared to be heavily influenced by weather, particularly precipitation during the breeding season. Received 13 August 2011. Accepted 15 December 2011., The Black-capped Vireo (Vireo atricapilla) is a federally endangered migratory songbird (Ratzlaff 1987) with a current known breeding range extending from central Oklahoma south through Texas to the Mexican states [...]

We describe the removal (predation) of a black-capped vireo (Vireo atricapilla) nestling by a female greater arid-land katydid (Neobarrettia spinosa) in southwest Texas. The event was captured with a nest camera during night in Jun. 2010. Neobarrettia species are known to be aggressive and carnivorous, but this is the first report of a katydid depredating a songbird nest., INTRODUCTION Species within the genus Neobarrettia are large, nocturnal, predaceous katydids that occur in Texas and northern Mexico as well as localized distributions in Kansas, Oklahoma, and New Mexico (Cohn, [...]

Habitat heterogeneity and corresponding diversity in potential prey species should increase the diet breadth of generalist predators. Many previous studies describing puma Puma concolor diets in the arid regions of the southwestern United States were focused within largely xeric locations, overlooking the influence of heterogeneity created by riparian forests. Such habitat heterogeneity and corresponding prey diversity could influence prey availability and puma diet composition. We examined seasonal prey composition of pumas occupying areas with different habitat conditions representing riparian areas adjacent to the Rio Grande and xeric Chihuahuan Desert uplands in southern New Mexico. We collected prey composition data from 686 kill sites made by 17 (9 males and 8 females) GPS-collared pumas from 2014 to 2018. Diet composition included 32 different avian, aquatic, small mammal, and ungulate prey species. Prey composition varied, with more ungulate prey consumed by pumas inhabiting the upland desert areas and more aquatic prey consumed in the riparian bosque. Prey composition differed between seasons, with ungulate prey decreasing and aquatic prey increasing during the hot–dry season. Prey composition also varied between puma sex and habitat with females in the desert uplands consuming more small mammals than either males or females in riparian areas. The diverse diets of the pumas inhabiting the heterogeneous landscapes in southern New Mexico provide additional evidence that pumas have broad diets that are strongly influenced by the habitat and prey community that their home range encompasses. [ABSTRACT FROM AUTHOR]

Informed management of American black bears (Ursus americanus) requires knowledge of the distribution and pathology of diseases affecting the species. Little information is available on pathogen prevalence from black bear populations in the Southwest, US, and it is unknown how these infections may influence black bear populations or disease transmission. We captured New Mexico black bears (Ursus americanus amblyceps) during 2016–17 as part of a long-term monitoring project and opportunistically collected 36 blood samples from 12 female and 17 male black bears. We wanted to determine prior exposure to canine distemper virus, canine parvovirus, Yersinia pestis, Francisella tularensis, West Nile virus, Toxoplasma gondii, and the tick-borne pathogens, Anaplasma spp., Ehrlichia spp., Borrelia burgdorferi, Rickettsia spp., and Babesia spp. Approximately half (55%, 16/29) of the individuals sampled had antibodies to Y. pestis, and 37% (10/27) had antibodies to T. gondii. Prevalence of antibodies to West Nile virus, F. tularensis, and canine parvovirus were lower (i.e., 11, 10, and 3%, respectively). We detected no antibodies to canine distemper, B. burgdorferi, Rickettsia spp., or Babesia spp. We documented changes in antibody titer levels for both sexes of several recaptured black bears. Our data will inform managers of pathogen prevalence and distribution in black bears in north-central New Mexico and provide a vital baseline dataset for future pathogen monitoring. Additionally, these data support actions to minimize exposure through handling wild individuals or through hunter harvest activities. [ABSTRACT FROM AUTHOR]

• Historical forest management actions contributed to degraded habitat for mule deer. • We monitored habitat selection of mule deer in relation to restoration treatments and wildfires. • Mule deer generally avoided wildfire-burned areas and thinned areas <5 years old. • Mule deer selected for areas burned by prescribed fire and thinned areas ≥5 years old. Decades of fire suppression, logging, and overgrazing have led to increased densities of small diameter trees which have been associated with decreases in biodiversity, reduced habitat quality for wildlife species, degraded foraging conditions for ungulates, and more frequent and severe wildfires. In response, land managers are implementing forest restoration treatments using prescribed fire and thinning to mitigate the risk of catastrophic wildfires and improve habitat conditions for a variety of wildlife species. We monitored habitat selection by female mule deer (Odocoileus hemionus) in relation to forest restoration treatments and wildfires in northern New Mexico in 2015. Our specific objectives were to assess changes in forage abundance and determine habitat selection patterns of mule deer in relation to recent wildfires, forest restoration treatments, including duration of the post-treatment recovery, and other habitat characteristics. Herbaceous forage biomass was greater in wildfire-burned areas than in untreated areas or those treated with prescribed burns or thinning. Oak forage biomass was greater in wildfire-burned areas compared to prescribed burns, forest thinning, and untreated areas. However, thinned areas tended to have higher oak forage biomass than untreated areas. Mule deer selected for areas burned by prescribed fire and generally avoided wildfire-burned and thinned areas <5 years old. Mule deer strongly selected for thinned areas ≥5 years old. At both the landscape and home-range scale, grasslands were avoided during most seasons, pinyon-juniper woodlands were selected in winter, and oak vegetation and mixed-conifer forests were selected during summer. Our data suggests that mule deer may benefit from recent prescribed burns and older forest thinning, but the duration of post-treatment vegetation recovery influences the strength and direction of selection. Knowledge of the short- and long-term effects of restoration treatments will provide managers with the means to make more informed decisions regarding implementation of forest restoration and other vegetation treatments intended to benefit mule deer. [ABSTRACT FROM AUTHOR]

ABSTRACT: Demographic data indicated a population of elk (Cervus canadensis) in northern New Mexico had reduced juvenile recruitment, resulting in a concern over quality hunting opportunities. Following several years of low calf:female ratios of <25:100, we conducted a 4‐year study from 2009–2012 to identify reasons for poor recruitment and evaluated the role of predation and nutrition in limiting productivity. We captured and fixed ear‐tag radio transmitters to 245 elk calves (126 males, 119 females) to determine cause‐specific mortality and estimate calf survival. During the second half of our study, we implemented a new spring black bear (Ursus americanus) season resulting in higher spring black bear harvest and evaluated response in calf survival. We also quantified herd‐wide nutritional condition and productivity. We estimated percent ingesta‐free body fat (IFBF) and pregnancy rates by sampling 1,808 hunter‐harvested female elk from autumn through winter. The primary cause of summer mortality for calves across all years was black bear predation. Estimates for annual calf survival were greater when spring black bear harvest was moderate to high (0.44–0.47) compared to periods with lower bear harvest (0.33–0.35). For every additional bear harvested in spring, radio‐tagged elk calves were 2.4% more likely to survive the summer. Across years and age classes 82 ± 1% (SE) of females were pregnant. Pregnancy rate was greatest for prime‐aged (2–14 yr) females (88 ± 1%). Our herd‐wide estimate of IFBF for prime‐aged adult female elk was 11.9 ± 0.19% but varied by pregnancy and lactation status. Our results that black bear predation was the primary cause of summer calf mortality and that adult females were in adequate nutritional condition suggested that black bear predation was limiting population productivity. Additionally, calf survival was higher in drought years, the same years when targeted spring black bear harvest was implemented. Our results demonstrated that productivity could be increased by implementing a spring black bear harvest strategy targeted around calving areas and could be applied in other areas experiencing low elk calf survival. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

ABSTRACT: Considering advances in noninvasive genetic sampling and spatially explicit capture–recapture (SECR) models, the New Mexico Department of Game and Fish sought to update their density estimates for American black bear (Ursus americanus) populations in New Mexico, USA, to aide in setting sustainable harvest limits. We estimated black bear density in the Sangre de Cristo, Sandia, and Sacramento Mountains, New Mexico, 2012–2014. We collected hair samples from black bears using hair traps and bear rubs and used a sex marker and a suite of microsatellite loci to individually genotype hair samples. We then estimated density in a SECR framework using sex, elevation, land cover type, and time to model heterogeneity in detection probability and the spatial scale over which detection probability declines. We sampled the populations using 554 hair traps and 117 bear rubs and collected 4,083 hair samples. We identified 725 (367 male, 358 female) individuals. Our density estimates varied from 16.5 bears/100 km2 (95% CI = 11.6–23.5) in the southern Sacramento Mountains to 25.7 bears/100 km2 (95% CI = 13.2–50.1) in the Sandia Mountains. Overall, detection probability at the activity center (g0) was low across all study areas and ranged from 0.00001 to 0.02. The low values of g0 were primarily a result of half of all hair samples for which genotypes were attempted failing to produce a complete genotype. We speculate that the low success we had genotyping hair samples was due to exceedingly high levels of ultraviolet (UV) radiation that degraded the DNA in the hair. Despite sampling difficulties, we were able to produce density estimates with levels of precision comparable to those estimated for black bears elsewhere in the United States. © 2018 The Wildlife Society. [ABSTRACT FROM AUTHOR]

The increase of tree density in forests of the American Southwest promotes extreme fire events, understory biodiversity losses, and degraded habitat conditions for many wildlife species. To ameliorate these changes, managers and scientists have begun planning treatments aimed at reducing fuels and increasing understory biodiversity. However, spatial variability in tree density across the landscape is not well-characterized, and if better known, could greatly influence planning efforts. We used reflectance values from individual Landsat 8 bands (bands 2, 3, 4, 5, 6, and 7) and calculated vegetation indices (difference vegetation index, simple ratios, and normalized vegetation indices) to estimate tree density in an area planned for treatment in the Jemez Mountains, New Mexico, characterized by multiple vegetation types and a complex topography. Because different vegetation types have different spectral signatures, we derived models with multiple predictor variables for each vegetation type, rather than using a single model for the entire project area, and compared the model-derived values to values collected from on-the-ground transects. Among conifer-dominated areas (73% of the project area), the best models (as determined by corrected Akaike Information Criteria (AICc)) included Landsat bands 2, 3, 4, and 7 along with simple ratios, normalized vegetation indices, and the difference vegetation index (R2 values for ponderosa: 0.47, piñon-juniper: 0.52, and spruce-fir: 0.66). On the other hand, in aspen-dominated areas (9% of the project area), the best model included individual bands 4 and 2, simple ratio, and normalized vegetation index (R2 value: 0.97). Most areas dominated by ponderosa, pinyon-juniper, or spruce-fir had more than 100 trees per hectare. About 54% of the study area has medium to high density of trees (100-1000 trees/hectare), and a small fraction (4.5%) of the area has very high density (>1000 trees/hectare). Our results provide a better understanding of tree density for identifying areas in need of treatment and planning for more effective treatment. Our analysis also provides an integrated method of estimating tree density across complex landscapes that could be useful for further restoration planning. [ABSTRACT FROM AUTHOR]

Although well studied in coastal ecosystems, comparatively little information exists on the ecology of inland Alligator mississippiensis (American Alligator) populations, particularly at the periphery of their range. Our specific objectives were to estimate home-range area and assess diel (i.e., day vs. night) habitat-selection patterns of an urban, inland American Alligator population at the northwestern edge of the species' range. During 2010– 2011, we captured 14 (6 female, 5 male, 3 unknown sex) American Alligators, 9 (5 female and 4 male) of which were fitted with VHF transmitters. Mean home range (95% kernel) was 68.9 ha (SD = 31.6) and 40.9 ha (SD = 20.7) and the mean core area (50% kernel) was 20.6 ha (SD = 18.5) and 10.1 ha (SD = 6.6) for males and females, respectively. American Alligators primarily selected river channels and open-canopy shorelines during both day and night. The amount of emergent or floating vegetation and canopy cover in a particular habitat influenced the probability of selection by American Alligators but this probability was dependent on the diel time period. During the day, the probability of selection was higher in areas with emergent or floating vegetation and more canopy cover, whereas at night the probability of selection decreased with increasing canopy cover. American Alligators did not select open water at either the study-area level or within the home range, which may have been due at least in part to the presence of recreational boaters or differences in food availability between open-water areas and other areas occupied by American Alligators on the Fort Worth Nature Center and Refuge. Overall, the results of our study are largely incongruent with patterns of home-range size and habitat selection reported for the species elsewhere, suggesting that further study of other American Alligator populations at the periphery of the distribution range is warranted. [ABSTRACT FROM AUTHOR]

Low lamb recruitment is a major challenge facing managers attempting to mitigate the decline of bighorn sheep (Ovis canadensis), and investigations into the underlying mechanisms are limited because of the inability to readily capture and monitor bighorn sheep lambs. We evaluated 4 capture techniques for bighorn sheep lambs: 1) hand-capture of lambs from radiocollared adult females fitted with vaginal implant transmitters (VITs), 2) hand-capture of lambs of intensively monitored radiocollared adult females, 3) helicopter net-gunning, and 4) hand-capture of lambs from helicopters. During 2010-2012, we successfully captured 90% of lambs from females that retained VITs to ⩽1 day of parturition, although we noted differences in capture rates between an area of high road density in the Black Hills (92-100%) of South Dakota, USA, and less accessible areas of New Mexico (71%), USA. Retention of VITs was 78% with prepartum expulsion the main cause of failure. We were less likely to capture lambs from females that expelled VITs ⩾1 day of parturition (range=80-83%) or females that were collared without VITs (range=60-78%). We used helicopter net-gunning at several sites in 1999, 2001-2002, and 2011, and it proved a useful technique; however, at one site, attempts to capture lambs led to lamb predation by golden eagles (Aquila chrysaetos). We attempted helicopter hand-captures at one site in 1999, and they also were successful in certain circumstances and avoided risk of physical trauma from net-gunning; however, application was limited. In areas of low accessibility or if personnel lack the ability to monitor females and/or VITs for extended periods, helicopter capture may provide a viable option for lamb capture. [ABSTRACT FROM AUTHOR]

Capra ibex Linnaeus, 1758, is a bovid commonly called the Alpine ibex that is sexually dimorphic. Body mass and scimitar-shaped horns are more than twice as large in males as in females. There are 8 extant species in the genus Capra. C. ibex is endemic to the Alpine Range of central Europe, was eliminated throughout its range except the Italian Alps, and has since been translocated to the Alps of Austria, France, Germany, Italy, Slovenia, and Switzerland at elevations of 1,600- 3,200 m. Habitat selection by C. ibex is mainly influenced by the gradient and extension of mountain slopes. It is not a species of special conservation concern and has increased to >20,000 individuals. [ABSTRACT FROM AUTHOR]

In arid regions of the southwestern United States, water is often considered a primary factor limiting distribution and productivity of desert ungulates, including desert bighorn sheep (Ovis canadensis mexicana). Thus, wildlife management agencies and sportsmen's organizations have invested substantial time and resources in the construction and maintenance of water catchments. Although the availability of freestanding water sources is believed to influence many aspects of the ecology of desert bighorn sheep, the efficacy of these water sources has been questioned and has not been examined experimentally. We used a before-after-control-impact study design to determine if removal of water catchments changed diet, characteristics of foraging areas used by female desert bighorn sheep, home-range size, movement rates, distance to catchments, adult mortality, productivity, or juvenile recruitment in 2 mountain ranges on the Cabeza Prieta National Wildlife Refuge, Arizona, USA. During pretreatment (2002-2003), we ensured that water catchments were available to desert bighorn sheep in both mountain ranges; during posttreatment (2004-2005), we drained all water catchments in the treatment range. We measured diet composition, characteristics of foraging areas, 50% and 95% kernel home ranges, movement rates, and distance to water catchments seasonally from 2002 to 2005. We also estimated adult survival, lamb:female, and yearling:female ratios from 2002 to 2005. We predicted that removal of water catchments would result in 1) increased use of foraging areas with more vegetation cover, more thermal cover, and higher succulent abundance; 2) increased consumption of cacti and other succulents; 3) an increase in home-range size, movement rates, and distance to nearest catchment; and 4) a decrease in adult survival, productivity, and juvenile recruitment. Removal of water catchments in the treatment range did not result in predicted changes in diet, foraging area selection, home-range size, movement rates, mortality, productivity, or recruitment. Female desert bighorn sheep did use areas with more thermal cover during the summer after removal of water catchments, but other characteristics of foraging areas used by bighorn sheep and their diet did not change appreciably with removal of water catchments. We did not document changes in home-range area, movement rates, or distance sheep were from water during hotter months; we only documented changes in home-range area, movement rates, and distance to water catchments during winter and autumn. There were 10 desert bighorn sheep mortalities in the treatment range and 8 in the control range; 7 mortalities in each mountain range were during pretreatment. Twelve of the 18 total mortalities occurred during summer. Survival rate was lower during pretreatment than posttreatment in both mountain ranges. We did not document increased mortality or a change in lamb:female or yearling:female ratios after removal of water catchments. Home-range area and movement rates declined with increasing precipitation. Annual survival rates increased with increases in the current year's total precipitation and total precipitation during the previous year; annual survival rates declined with increases in average daily temperature during winter. There was a severe drought during pretreatment and abnormally wet conditions during posttreatment. The increase in precipitation that coincided with removal of water sources improved forage conditions during posttreatment and may have provided adequate water for female desert bighorn sheep. The lack of change in home-range size, movement rates, and distance to the nearest water catchment during hot, dry seasons after removal of water sources suggests that forage conditions played a greater role in determining home-range area and movement rates than did the presence of water catchments.… [ABSTRACT FROM AUTHOR]

Concern about the habitat requirements of sable antelope (Hippotragus niger) has increased due to population declines shown in some protected areas. Our study was prompted by the lack of initial increase by the sable antelope introduced into the Pilanesberg Game Reserve in North West Province, South Africa; 67 animals released between 1979 and 1983 had only grown to approximately 70 animals by 1988. We recorded forage selection by sable antelope within the context of the landscape units favoured in different seasons. Chrysopogon serrulatus, Panicum maximum, Heteropogon contortus, and Themeda triandra contributed most to the diet of sable antelope. Faecal crude protein content did not drop below 6.6% of dry matter during the dry season, with use of burnt grassland by sable contributing to an elevation in faecal protein levels at the beginning of the wet season. The sable population had increased to 127 animals by 1991, suggesting that the earlier lack of population growth had been due to below-average rainfall, lack of burns providing green regrowth during the dry season, or a delay in learning to exploit available forage resources efficiently. [ABSTRACT FROM AUTHOR]

The United States Air Force (USAF) uses part of Sonoran pronghorn (Antilocapra americana sonoriensis) habitat for bombing exercises (i.e., Barry M. Goldwater Air Force Range [BMGR], southwest AZ, USA) that could be detrimental to the endangered subspecies. To minimize injury or death to Sonoran pronghorn, the USAF and United States Fish and Wildlife Service developed a monitoring protocol that would eliminate live ordnance delivery in the vicinity of pronghorn. From 1998 to 2003, we searched for pronghorn on or near military targets prior to ordnance delivery. If we observed pronghorn within 5 km of a target, the target was closed for ≥24 hours. We monitored bombing ranges on BMGR and closed >5,000 targets for >1,000 days due to military activity. To our knowledge, no pronghorn were killed or injured. We recommend that the monitoring program continue as long as military activity occurs in pronghorn habitat. [ABSTRACT FROM AUTHOR]

GPS/GSM collars were fitted to females in two sable antelope herds occupying adjoining home ranges in the Kruger National Park in order to establish their movement responses to seasonally changing resource availability. This investigation formed part of a larger study aimed at identifying the factors responsible for the substantial population declines by this and other rarer antelope species in the protected area. To indicate responses to stressful periods during the seasonal cycle, we used the following measures: (a) proportion of locations outside the home range core, (b) displacement distances from day to day in foraging locations, and (c) extent of movement at night versus during daylight. Movements beyond the home range core were affected by excursions to water as well as foraging locations. When food and water availability became restricted during the dry season, one herd extended its range well beyond the core region favored during the wet season, while the other herd concentrated its space use more tightly within the core region, except during excursions to water. Journeys to water also affected the patterns shown by diel (24 h) displacements calculated between morning versus evening foraging locations. Diel displacement distances between evening locations were minimal when both food and water were plentifully available, and were greatest for one herd during the late dry season, but for the other herd when rainfall deficits occurred during a wet season month. Nocturnal movement showed a peak in the transition period between the dry and wet season when both resources were restricted and prevailing temperatures high. Hence, while these measures did indicate periods when resources became restricted, results revealed some of the complexities due to interactions between food and water availability. Findings also emphasised the limited extent of the landscape upon which sable depended for their resource requirements. [ABSTRACT FROM AUTHOR]

Desert ungulates must contend with high solar radiation, high ambient temperatures, a lack of water and cover, unpredictable food resources, and the challenges these factors present for thermoregulation and water balance, To deal with the conflicting challenges of maintaining body temperature within acceptable limits and minimizing water loss, desert ungulates use a variety of physiological, morphological, and behavioral mechanisms. The mechanisms involved m thermoregulation and water balance have been studied in many domestic and wild African and Middle Eastern ungulates; studies involving ungulates inhabiting North American deserts are limited in comparison. Our objectives were to review available scientific literature on thermoregulation, water balance, and the effects of dehydration in desert ungulates. We discuss the physiological, morphological, and behavioral mechanisms used by ungulates to maintain temperature and water balance in arid environments, and the implications for research and management of desert ungulates in western North America. [ABSTRACT FROM AUTHOR]

Human-made or -modified water sources (i.e., catchments) are widely used for wildlife management in the arid western United States, where thousands of such catchments have been built to enhance wildlife populations and mitigate for the loss of natural water sources. For decades, the need for and value of catchments to wildlife was unquestioned. Recently, however, the use of catchments has become controversial, particularly on public lands. Impacts to wildlife populations and wildlife habitats have been central to the debate, which has, in large part, been fueled by a paucity of scientific information. Value-based conflicts over management practices on public lands also have played a significant role. [ABSTRACT FROM AUTHOR]

For many avian species, predation is the leading cause of nest failure. However, relationships between predator abundance and nest predation often differ across spatial scales. We examined the relationship between environmental characteristics in meadows and mammalian predator activity, the relationship between predator activity at 2 spatial scales, and the probability of nest predation of willow flycatchers (Empidonax traillii), dusky flycatchers (Empidonax oberholseri), and yellow warblers (Dendroica petechia) in the central Sierra Nevada Mountains, California, USA. Environmental characteristics associated with the detection of nest predators varied depending on species. Douglas's squirrel (Tamiasciurus douglasii) and chipmunks (Tamias spp.) were associated with characteristics common along edges of meadows; short-tailed weasels (Mustela erminea) were associated with willows, whereas mice (Peromyscus maniculatus, Reithrodontomys megalotis, and Microtus spp.) and long-tailed weasels (Mustela frenata) were distributed throughout the meadows. The probability of predation of willow and dusky flycatcher nests increased with increasing short-tailed weasel activity, and the probability of predation of yellow warbler nests increased with increasing activity of chipmunks and short-tailed weasels. Variation in the occurrence of predator species in different areas of the meadows likely influences the probability of nest predation by each species and the nesting success of birds. Identifying factors that influence the distribution and abundance of common nest predators will likely be integral to the development of conservation efforts to increase the reproductive success of some bird species. [ABSTRACT FROM AUTHOR]

Topography, vegetation, and animal behavior may influence the performance of Global Positioning System (GPS) telemetry collars, affecting fix success rates and location error. We reviewed the scientific literature published from 1995 to June 2004 to determine the fix intervals used and fix success rates obtained in studies using GPS telemetry. We also programmed GPS telemetry collars with 6 different fix intervals and placed them at fixed locations of varying topography in the Cabeza Prieta National Wildlife Refuge, Arizona from August 2003-May 2004. Fix interval affected fix success rates both in our field study (99, 98, 96, 94, 93, 92% fix success rate for 0.25, 0.5, 1, 4, 6, and 13-hour fix intervals, respectively) and in our analysis of data obtained from scientific literature (r²=0.531, P≤ 0.001), with shorter fix intervals being associated with higher fix success rates. Topography affected the fix success rate (F2 77=12.017, P≤0.001), location error (F2,77 = 6.76, P=0.002), and proportion of 3-dimensional (3-D) fixes (F2 77=10.184, P≤0.001), resulting in lower fix success rates and larger location errors in areas with more rugged topography. The influence of topography and fix interval on location error and fix success rates may bias GPS location data, resulting in misclassification of habitat use and under-sampling certain areas used by animals. Location error and missing data can increase type II error and may result in incorrect inferences in some studies. These biases need to be assessed and steps should be taken to minimize their influence on results of studies of habitat selection and other aspects of animal ecology. [ABSTRACT FROM AUTHOR]

The article presents information of mammalian species namely Antidorcas marsupialis, springbok. Springbok has Order Artiodactyla, family Bovidae, subfamily Antilopinae, Antilopini and genus Antidorcas. Antidorcas is monotypic. Antidorcas has 5 pairs of grinding teeth, both sexes have horns, anteorbital fossae are present in skull, and pedal glands are located immediately above hoofs. Fossils of Antidorcas are reported from Pliocene, Pleistocene, and Holocene localities in northern, southern eastern Africa. Springbok are opportunistic breeders and mate year-round.

Focuses on a study which examined the association between telemetry marking collars, incorporating Global Positioning System receivers and transmitters, and neck injuries in mule deer and mountain sheep. Types of injury inflicted by telemetry collars; Analysis of the presence of bacteria in collar-induced injuries; Factors that need to be considered in designing telemetry collar.

Presents a study that investigated the predator activity and nest success of willow flycatchers and warblers in Sierra Nevada, California. Decline in the population of the species; Identification of nest predators used in the study; Relationship between nest success and proximity to the forest edge.

Presents a study that examined the frequency of excluding rare animal species from community level analyses for wildlife management. Assessment of the number of species sampled and the number of species included in community-level analyses in different wildlife-related journals; Calculation of the percentage of species excluded from articles published in wildlife-related journals; Implications of the study for wildlife management.

• Bed site selection is associated with lower horizontal visibility and high stand basal area. • Den site selection is associated with low horizontal visibility. • There was little support for sex- or season-specific differences in bed or den site selection. • Black bears used some disturbed sites, but bed sites and den sites were mostly in undisturbed areas. • Wildfire and restoration treatments may alter habitat use until vegetation recovery has occurred. The combined effects of long-term fire suppression, logging, and overgrazing have negatively impacted many southwestern U.S. forests, resulting in decreased habitat quality for wildlife, and more frequent and severe wildfires. In response, land management agencies are implementing large-scale forest restoration treatments, but data on how wildlife respond to restoration treatments and wildfires are often limited. We investigated bed and den site selection of American black bears (Ursus americanus) using GPS location data and a use/available study design to assess the influence of habitat characteristics, including wildfires, prescribed burns, and thinning treatments on bed and den site selection in the Jemez Mountains, New Mexico. The most supported models suggested that black bears were more likely to select bed sites with a combination of low horizontal visibility (β = −0.007, SE = 0.002; P = 0.002) and high stand basal area (β = 0.013, SE = 0.005; P = 0.004). The highest-ranking model for den site selection indicated that black bears were more likely to select den sites with low horizontal visibility (β = −0.0102, SE = 0.004; P = 0.006). Black bears used all disturbed sites to varying degrees (45% of study area), although 48% of bed sites were located in undisturbed habitat (55% of study area) while only 11% and 2% of bed sites were located in thinned and prescribed burn sites, respectively. Thirty-nine percent of bed sites were located in previous wildfire locations; however, 67% of these sites were in areas with low burn severity. Thirty-eight percent of den sites were located in previously disturbed habitat, 8 of these sites were burned by wildfires. In order to develop effective management plans for black bears, it is essential to understand responses to landscape-scale habitat disturbances due to wildfires and restoration activities, all of which are becoming more prevalent and widespread across southwestern forests. Accounting for the timing, size, and proximity of future restoration efforts would aid in mitigating potential short-term negative effects on black bears. [ABSTRACT FROM AUTHOR]

Occupancy models have become a valuable tool for estimating wildlife-habitat relationships and for predicting species distributions. Highly-mobile species often violate the assumption that sampling units are geographically closed shifting the probability of occupancy to be interpreted as the probability of use. We used occupancy models, in conjunction with noninvasive sampling, to estimate habitat use and predict the distribution of a highly-mobile carnivore, the American black bear (Ursus americanus) in New Mexico, USA. The top model indicated that black bears use areas with higher primary productivity and fewer roads. The predictive performance of such models is rarely validated with independent data, so we validated our model predictions with 2-independent datasets. We first assessed the correlation between predicted and observed habitat use for 28 telemetry-collared bears in the Jemez Mountains. Predicted habitat use was positively correlated with observed use for all 3 years (2012: ρ = 0.81; 2013: ρ = 0.87; 2014: ρ = 0.90). We then predicted the probability of use within a cell where a bear mortality was documented using 2043 mortality locations from sport harvest, depredation, and vehicle collisions. The probability of habitat use at a mortality location was also positively correlated with observed use by the species (2012: ρ = 0.74; 2013: ρ = 0.89; 2014: ρ = 0.93). Our validation procedure supports the notion that occupancy models can be an effective tool for estimating habitat use and predicting the distribution of highly-mobile species when the assumption of geographic closure has been violated. Our findings may be of interest to studies that are estimating habitat use for highly-mobile species that are secretive or rare, difficult to capture, or expensive to monitor with other more intensive methods. [ABSTRACT FROM AUTHOR]

This article presents information related to the management for the survival of Sonoran pronghorn in the U.S. In 2000 the population of pronghorn was estimated at 799,200. Currently there are 5 recognized subspecies of pronghorn based on differences in color, size, and form--American pronghorn (A.a. americana), Mexican pronghorn (A.a. mexicana), peninsular pronghorn (A.a. peninsularis), Oregon pronghorn (A.a. oregona), and Sonoran pronghorn (A.a. sonoriensis). In the past decade, dedicated and determined individuals from the Arizona Game and Fish Department and the United States Fish and Wildlife Service initiated recovery efforts that had been proposed for nearly 3 decades. With Sonoran pronghorn numbers low, it is critical that biologists in the U.S. continue to work with biologists in Mexico to minimize effects of bottlenecks. The data are being carefully monitored, and biologists are approaching recovery in a positive manner. Without such efforts, the indigenous Sonoran pronghorn population in the U.S. could become a memory.

Abstract Increasing tree canopy cover has led to increasing wildfire activity in conifer dominated areas of the southwestern United States. Estimating historical changes in the spatial distribution of tree canopy cover can provide further insights into the dynamics of forest and fuel conditions in these landscapes and help prioritize areas for restoration to mitigate wildfire risks and restore biological functioning. In this study, we explored the relationship between LiDAR derived canopy cover data and Landsat reflectance values, and derived a model to estimate percent canopy cover (PCC) on historical Landsat data from 1987 to 2015 for the Valles Caldera National Preserve (VCNP), located in the southwest Jemez Mountains of New Mexico. We developed a regression model between LiDAR generated canopy cover collected in June 2010 and Landsat Thematic Mapper (TM) reflectance values (bands 1–7 except band 6) and vegetation indices collected for the same date. About 5% (17,000) of the total LiDAR points (329,102) were used as training points and a separate, non-overlapping set of 17,000 points as test points to validate the regression model. A simple linear model with the red band (band 3; R 2 = 0.70) was selected as the best model to predict PCC in the rest of the images for 1987–2015. In general, we found a strong consistency between the spatial dynamics of modelled tree canopy cover based on historical Landsat data, wildfire events and forest management practices that occurred during the same period. Results showed that about 11% of the study area experienced an increase in PCC for the period of 1987–2015 while 41% of the study area experienced a reduction in PCC during the same time period, mostly in the areas which were affected by stand replacing wildfires in 2011 and 2013. The results indicate an overall increase in medium and high canopy cover classes in specific regions of the study area, which could lead to hazardous wildfires such as those in 2011 and 2013. In the context of ongoing ecological restoration of these montane forests, predicted PCC of contemporary forests could help local managers to identify the areas in the need of immediate restoration efforts by focusing management practices on the areas with closed canopy. Highlights • We integrated LiDAR and Landsat data to estimate canopy cover dynamics in conifer forests of southwestern United States. • Analysis showed that Landsat TM band 3 (red) as the best predictor of LiDAR derived percent canopy cover (R 2 = 0.70). • We found an overall increase in percent canopy cover (1987–2015) except the areas affected by stand-replacing wildfires. • The findings could help local forest managers to identify potential areas for ecological restoration. [ABSTRACT FROM AUTHOR]

Vireo atricapilla (Black-capped Vireo) is an endangered songbird whose habitat use has been well studied in central portions of its breeding range, which is characterized by successional vegetation communities. To expand our understanding of habitat use as it relates to reproductive success, we studied Black-capped Vireo habitat use at the territory and nest-site scales in southwest Texas in 2009 and 2010, an area characterized by xeric and stable vegetation communities. We measured vegetation in territories and at nests to evaluate the influence of habitat variables on nest parasitism and nest survival. Our results showed that Black-capped Vireo nest-site use in southwest Texas differed from that in breeding areas of central Texas and Oklahoma. Black-capped Vireos in southwest Texas used nest sites with a wide range of woody cover (70 ±13%) and used Juniperus spp. (junipers) as a nest substrate proportionately more than its availability in territories, which is contradictory to previously published literature. Nest parasitism increased significantly with greater nest height, likely due to increased visibility to Molothrus ater (Brown-headed Cowbird). Increasing height of vertical cover above the nest was associated with decreased overall nest survival, likely because nests placed in habitat with taller vegetation are more susceptible to avian predators and Brown-headed Cowbird parasitism. Unlike the findings of studies conducted in the northern part of the species'breeding range, we found that parasitism did not increase the likelihood of depredation or abandonment. Our results indicate that Black-capped Vireo habitat structure and composition, as well as factors influencing nest success in Southwest Texas, differ from their breeding habitat in central Texas and Oklahoma, indicating that management guidelines need to be regi on-specific. [ABSTRACT FROM AUTHOR]

During March 2001-December 2003, we measured use of forage and height of stubble in pastures at low, middle, and high elevations. In years with higher precipitation, use of forage by cattle (Bos taurus) and elk (Cervus elaphus) was less in the middle elevation compared to low and high elevations. In the worst drought year on record (2002), use of forage increased with elevation. Overall, use of forage was greater in 2002 than in 2001 and 2003. Shorter stubble corresponded to lower production and higher use of forage. Total use of forage did not exceed 50%. [ABSTRACT FROM AUTHOR]