The Experts below are selected from a list of 5136 Experts worldwide ranked by ideXlab platform
Susan Lingle - One of the best experts on this subject based on the ideXlab platform.
-
Male size and alternative mating tactics in white-tailed Deer and Mule Deer
Journal of Mammalogy, 2020Co-Authors: Jason I Airst, Susan LingleAbstract:Abstract Within populations, individual males adopt different courtship tactics due to differences in their competitive ability, which may vary depending on the animal’s age and size. To test the hypothesis that Mule Deer (Odocoileus hemionus) and white-tailed Deer (O. virginianus) males vary their courtship behavior based on their size, we conducted focal observations of 144 Mule Deer and 85 white-tailed males that varied in size, at a large grassland site in southern Alberta. The smallest Mule Deer males devoted more time to feeding, were less likely to engage in late-stage courtship than larger males and were less likely to move among female groups. Other males, including small white-tailed males, appeared to use a roving strategy to search for estrous females in different groups, which is consistent with recent research on male movements. Both medium and large males increased the time they spent in one-male groups, and specifically isolated pairs, as courtship advanced, presumably to reduce competition with other males. However, this trend was most pronounced for medium Mule Deer males, and for all size classes of white-tailed Deer. In contrast, large Mule Deer males spent a similar proportion of time tending females in all group types. Our results identified potential size-dependent tactics for Mule Deer males. In contrast, white-tailed males of all sizes appeared to rely on a tactic of finding and tending estrous females in isolation from other males.
-
interspecific variation in antipredator behaviour leads to differential vulnerability of Mule Deer and white tailed Deer fawns early in life
Journal of Animal Ecology, 2005Co-Authors: Susan Lingle, Sergio M. Pellis, Finbarr W WilsonAbstract:Summary 1 Ungulates are viewed as being highly susceptible to predation during the initial weeks or months of life. Yet aggressive defence by adult females is common in many ungulates and has the potential to reduce the vulnerability of the young significantly. 2 We observed naturally occurring predatory encounters between coyotes Canis latrans Say and Deer fawns to test the hypothesis that a difference in aggressive defence leads to the differential vulnerability of Mule Deer Odocoileus hemionus Rafinesque and white-tailed Deer O. virginianus Zimmermann fawns in summer, when fawns are 0–14 weeks in age. Whitetail fawns suffer higher levels of coyote predation than do Mule Deer fawns at that time. The two species of Deer are similar in size, but are known to differ in their antipredator behaviour in winter when fawns are older. 3 Coyotes were less likely to attack Mule Deer than whitetail fawns they encountered, and were less likely to kill Mule Deer than whitetail fawns they attacked. 4 The presence of a Mule Deer, but not a whitetail, female with a fawn deterred coyotes from attacking the fawn. Once attacked, fawns of both species were less likely to be killed when females defended them, but Mule Deer females were far more likely to defend fawns. 5 Mule Deer females defended fawns that were not their own offspring, including heterospecific fawns. Mule Deer fawns were more likely to be defended if they had a larger number of females nearby when encountered. These observations raise the possibility that Mule Deer, and even whitetail, fawns may have improved survival in areas with higher densities of Mule Deer females. 6 These results show that higher levels of defence by Mule Deer females reduced the vulnerability of Mule Deer fawns, contributing to the lower predation rates reported for Mule Deer than for whitetail fawns of this age group.
-
Interspecific variation in antipredator behaviour leads to differential vulnerability of Mule Deer and white‐tailed Deer fawns early in life
Journal of Animal Ecology, 2005Co-Authors: Susan Lingle, Sergio M. Pellis, W. Finbarr WilsonAbstract:Summary 1 Ungulates are viewed as being highly susceptible to predation during the initial weeks or months of life. Yet aggressive defence by adult females is common in many ungulates and has the potential to reduce the vulnerability of the young significantly. 2 We observed naturally occurring predatory encounters between coyotes Canis latrans Say and Deer fawns to test the hypothesis that a difference in aggressive defence leads to the differential vulnerability of Mule Deer Odocoileus hemionus Rafinesque and white-tailed Deer O. virginianus Zimmermann fawns in summer, when fawns are 0–14 weeks in age. Whitetail fawns suffer higher levels of coyote predation than do Mule Deer fawns at that time. The two species of Deer are similar in size, but are known to differ in their antipredator behaviour in winter when fawns are older. 3 Coyotes were less likely to attack Mule Deer than whitetail fawns they encountered, and were less likely to kill Mule Deer than whitetail fawns they attacked. 4 The presence of a Mule Deer, but not a whitetail, female with a fawn deterred coyotes from attacking the fawn. Once attacked, fawns of both species were less likely to be killed when females defended them, but Mule Deer females were far more likely to defend fawns. 5 Mule Deer females defended fawns that were not their own offspring, including heterospecific fawns. Mule Deer fawns were more likely to be defended if they had a larger number of females nearby when encountered. These observations raise the possibility that Mule Deer, and even whitetail, fawns may have improved survival in areas with higher densities of Mule Deer females. 6 These results show that higher levels of defence by Mule Deer females reduced the vulnerability of Mule Deer fawns, contributing to the lower predation rates reported for Mule Deer than for whitetail fawns of this age group.
-
Anti-Predator Strategies and Grouping Patterns in White-Tailed Deer and Mule Deer
Ethology, 2001Co-Authors: Susan LingleAbstract:White-tailed Deer (Odocoileus virginianus) and Mule Deer (O. hemionus) are closely related species of similar size that differ in their anti-predator behavior. White-tails flee from coyotes (Canis latrans), whereas Mule Deer typically stand their ground and attack this predator. I used observations of coyotes hunting Deer to identify: (i) changes in group structure made in response to coyotes; and (ii) the relationship between group structure and the risk of predation for each species. In response to coyotes, groups of Mule Deer merged with other groups and individuals bunched together. Predation attempts were more likely to escalate when groups split and individuals failed to bunch. Coyotes typically attacked Mule Deer that were in outlying positions, and these Deer had to move to central positions to end attacks. Due to the high frequency of attacks on small groups as well as to the level of dilution of risk, individuals in small Mule Deer groups were at high risk of being attacked compared with those in larger groups. In contrast to Mule Deer, white-tails made no consistent changes in group size or formation, and coyotes attacked individuals in central as well as in outlying positions. Variation in aspects of group cohesion was not related to the vulnerability of white-tails, and there was no obvious difference in the risk of attack facing individuals in groups of different size. These results suggest that coyote predation selects for relatively large, cohesive groups in Mule Deer, apparently because this type of group improves their ability to deter coyotes. Coyote predation does not have similar effects on groups formed by white-tails, which use flight rather than deterrence to avoid predation. The benefits of responding cohesively, occupying certain positions within groups, and forming groups of a certain size can vary widely depending on the anti-predator strategies used by an animal.
-
Detection and Avoidance of Predators in White-Tailed Deer (Odocoileus virginianus) and Mule Deer (O. hemionus)
Ethology, 2001Co-Authors: Susan Lingle, W. Finbarr WilsonAbstract:In this paper, we investigate the relationship between early detection of predators and predator avoidance in white-tailed Deer (Odocoileus virginianus) and Mule Deer (O. hemionus), two closely related species that differ in their habitat preferences and in their anti-predator behavior. We used observations of coyotes (Canis latrans) hunting Deer to test whether the distance at which white-tails and Mule Deer alerted to coyotes was related to their vulnerability to predation. Coyote encounters with both species were more likely to escalate when Deer alerted at shorter distances. However, coyote encounters with Mule Deer progressed further than encounters with white-tails that alerted at the same distance, and this was not due to species differences in group size or habitat. We then conducted an experiment in which a person approached groups of Deer to compare the detection abilities and the form of alert response for white-tails and Mule Deer, and for age groups within each species. Mule Deer alerted to the approacher at longer distances than white-tails, even after controlling for variables that were potentially confounding. Adult females of both species alerted sooner than conspecific juveniles. Mule Deer almost always looked directly at the approacher as their initial response, whereas white-tails were more likely to flee or to look in another direction with no indication that they pinpointed the approacher during the trial. Mule Deer may have evolved the ability to detect predators earlier than white-tails as an adaptation to their more open habitats, or because they need more time to coordinate subsequent anti-predator defenses.
Matthew J. Kauffman - One of the best experts on this subject based on the ideXlab platform.
-
endemic chronic wasting disease causes Mule Deer population decline in wyoming
PLOS ONE, 2017Co-Authors: Melia T Devivo, Matthew J. Kauffman, David R Edmunds, Brant A Schumaker, Justin Binfet, Terry J Kreeger, Bryan J Richards, Hermann M Schatzl, Todd E CornishAbstract:Chronic wasting disease (CWD) is a fatal transmissible spongiform encephalopathy affecting white-tailed Deer (Odocoileus virginianus), Mule Deer (Odocoileus hemionus), Rocky Mountain elk (Cervus elaphus nelsoni), and moose (Alces alces shirasi) in North America. In southeastern Wyoming average annual CWD prevalence in Mule Deer exceeds 20% and appears to contribute to regional population declines. We determined the effect of CWD on Mule Deer demography using age-specific, female-only, CWD transition matrix models to estimate the population growth rate (λ). Mule Deer were captured from 2010–2014 in southern Converse County Wyoming, USA. Captured adult (≥ 1.5 years old) Deer were tested ante-mortem for CWD using tonsil biopsies and monitored using radio telemetry. Mean annual survival rates of CWD-negative and CWD-positive Deer were 0.76 and 0.32, respectively. Pregnancy and fawn recruitment were not observed to be influenced by CWD. We estimated λ = 0.79, indicating an annual population decline of 21% under current CWD prevalence levels. A model derived from the demography of only CWD-negative individuals yielded; λ = 1.00, indicating a stable population if CWD were absent. These findings support CWD as a significant contributor to Mule Deer population decline. Chronic wasting disease is difficult or impossible to eradicate with current tools, given significant environmental contamination, and at present our best recommendation for control of this disease is to minimize spread to new areas and naive cervid populations.
-
conserving migratory Mule Deer through the umbrella of sage grouse
Ecosphere, 2014Co-Authors: Holly E. Copeland, Hall Sawyer, Kevin L. Monteith, David E. Naugle, Amy Pocewicz, N. Graf, Matthew J. KauffmanAbstract:Conserving migratory ungulates in increasingly human-dominated landscapes presents a difficult challenge to land managers and conservation practitioners. Nevertheless, ungulates may receive ancillary benefits from conservation actions designed to protect species of greater conservation priority where their ranges are sympatric. Greater Sage-Grouse (Centrocerus urophasianus), for example, have been proposed as an umbrella species for other sagebrush (Artemesia spp.)-dependent fauna. We examined a landscape where conservation efforts for sage-grouse overlap spatially with Mule Deer (Odocoileus hemionus) to determine whether sage-grouse conservation measures also might protect important Mule Deer migration routes and seasonal ranges. We conducted a spatial analysis to determine what proportion of migration routes, stopover areas, and winter ranges used by Mule Deer were located in areas managed for sage-grouse conservation. Conservation measures overlapped with 66–70% of migration corridors, 74–75% of stopovers, and 52–91% of wintering areas for two Mule Deer populations in the upper Green River Basin of Wyoming. Of those proportions, conservation actions targeted towards sage-grouse accounted for approximately half of the overlap in corridors and stopover areas, and nearly all overlap on winter ranges, indicating that sage-grouse conservation efforts represent an important step in conserving migratory Mule Deer. Conservation of migratory species presents unique challenges because although overlap with conserved lands may be high, connectivity of the entire route must be maintained as barriers to movement anywhere within the migration corridor could render it unviable. Where Mule Deer habitats overlap with sage-grouse core areas, our results indicate that increased protection is afforded to winter ranges and migration routes within the umbrella of sage-grouse conservation, but this protection is contingent on concentrated developments within core areas not intersecting with high-priority stopovers or corridors, and that the policy in turn does not encourage development on Deer ranges outside of core areas. With the goal of protecting entire migration routes, our analysis highlights areas of potential conservation focus for Mule Deer, which are characterized by high exposure to residential development and use by a large proportion of migrating Deer.
-
Conserving migratory Mule Deer through the umbrella of sage‐grouse
Ecosphere, 2014Co-Authors: Holly E. Copeland, Hall Sawyer, Kevin L. Monteith, David E. Naugle, Amy Pocewicz, N. Graf, Matthew J. KauffmanAbstract:Conserving migratory ungulates in increasingly human-dominated landscapes presents a difficult challenge to land managers and conservation practitioners. Nevertheless, ungulates may receive ancillary benefits from conservation actions designed to protect species of greater conservation priority where their ranges are sympatric. Greater Sage-Grouse (Centrocerus urophasianus), for example, have been proposed as an umbrella species for other sagebrush (Artemesia spp.)-dependent fauna. We examined a landscape where conservation efforts for sage-grouse overlap spatially with Mule Deer (Odocoileus hemionus) to determine whether sage-grouse conservation measures also might protect important Mule Deer migration routes and seasonal ranges. We conducted a spatial analysis to determine what proportion of migration routes, stopover areas, and winter ranges used by Mule Deer were located in areas managed for sage-grouse conservation. Conservation measures overlapped with 66–70% of migration corridors, 74–75% of stopovers, and 52–91% of wintering areas for two Mule Deer populations in the upper Green River Basin of Wyoming. Of those proportions, conservation actions targeted towards sage-grouse accounted for approximately half of the overlap in corridors and stopover areas, and nearly all overlap on winter ranges, indicating that sage-grouse conservation efforts represent an important step in conserving migratory Mule Deer. Conservation of migratory species presents unique challenges because although overlap with conserved lands may be high, connectivity of the entire route must be maintained as barriers to movement anywhere within the migration corridor could render it unviable. Where Mule Deer habitats overlap with sage-grouse core areas, our results indicate that increased protection is afforded to winter ranges and migration routes within the umbrella of sage-grouse conservation, but this protection is contingent on concentrated developments within core areas not intersecting with high-priority stopovers or corridors, and that the policy in turn does not encourage development on Deer ranges outside of core areas. With the goal of protecting entire migration routes, our analysis highlights areas of potential conservation focus for Mule Deer, which are characterized by high exposure to residential development and use by a large proportion of migrating Deer.
-
influence of well pad activity on winter habitat selection patterns of Mule Deer
Journal of Wildlife Management, 2009Co-Authors: Hall Sawyer, Matthew J. Kauffman, Ryan M NielsonAbstract:Abstract Conversion of native winter range into producing gas fields can affect the habitat selection and distribution patterns of Mule Deer (Odocoileus hemionus). Understanding how levels of human activity influence Mule Deer is necessary to evaluate mitigation measures and reduce indirect habitat loss to Mule Deer on winter ranges with natural gas development. We examined how 3 types of well pads with varying levels of vehicle traffic influenced Mule Deer habitat selection in western Wyoming during the winters of 2005–2006 and 2006–2007. Well pad types included producing wells without a liquids gathering system (LGS), producing wells with a LGS, and well pads with active directional drilling. We used 36,699 Global Positioning System locations collected from a sample (n = 31) of adult (>1.5-yr-old) female Mule Deer to model probability of use as a function of traffic level and other habitat covariates. We treated each Deer as the experimental unit and developed a population-level resource selection fun...
Hall Sawyer - One of the best experts on this subject based on the ideXlab platform.
-
Mule Deer and energy development long term trends of habituation and abundance
Global Change Biology, 2017Co-Authors: Hall Sawyer, Kevin L. Monteith, Nicole M Korfanta, Ryan M Nielson, Dale StricklandAbstract:As the extent and intensity of energy development in North America increases, so do disturbances to wildlife and the habitats they rely upon. Impacts to Mule Deer are of particular concern because some of the largest gas fields in the USA overlap critical winter ranges. Short-term studies of 2–3 years have shown that Mule Deer and other ungulates avoid energy infrastructure; however, there remains a common perception that ungulates habituate to energy development, and thus, the potential for a demographic effect is low. We used telemetry data from 187 individual Deer across a 17-year period, including 2 years predevelopment and 15 years during development, to determine whether Mule Deer habituated to natural gas development and if their response to disturbance varied with winter severity. Concurrently, we measured abundance of Mule Deer to indirectly link behavior with demography. Mule Deer consistently avoided energy infrastructure through the 15-year period of development and used habitats that were an average of 913 m further from well pads compared with predevelopment patterns of habitat use. Even during the last 3 years of study, when most wells were in production and reclamation efforts underway, Mule Deer remained >1 km away from well pads. The magnitude of avoidance behavior, however, was mediated by winter severity, where aversion to well pads decreased as winter severity increased. Mule Deer abundance declined by 36% during the development period, despite aggressive onsite mitigation efforts (e.g. directional drilling and liquid gathering systems) and a 45% reduction in Deer harvest. Our results indicate behavioral effects of energy development on Mule Deer are long term and may affect population abundance by displacing animals and thereby functionally reducing the amount of available habitat.
-
conserving migratory Mule Deer through the umbrella of sage grouse
Ecosphere, 2014Co-Authors: Holly E. Copeland, Hall Sawyer, Kevin L. Monteith, David E. Naugle, Amy Pocewicz, N. Graf, Matthew J. KauffmanAbstract:Conserving migratory ungulates in increasingly human-dominated landscapes presents a difficult challenge to land managers and conservation practitioners. Nevertheless, ungulates may receive ancillary benefits from conservation actions designed to protect species of greater conservation priority where their ranges are sympatric. Greater Sage-Grouse (Centrocerus urophasianus), for example, have been proposed as an umbrella species for other sagebrush (Artemesia spp.)-dependent fauna. We examined a landscape where conservation efforts for sage-grouse overlap spatially with Mule Deer (Odocoileus hemionus) to determine whether sage-grouse conservation measures also might protect important Mule Deer migration routes and seasonal ranges. We conducted a spatial analysis to determine what proportion of migration routes, stopover areas, and winter ranges used by Mule Deer were located in areas managed for sage-grouse conservation. Conservation measures overlapped with 66–70% of migration corridors, 74–75% of stopovers, and 52–91% of wintering areas for two Mule Deer populations in the upper Green River Basin of Wyoming. Of those proportions, conservation actions targeted towards sage-grouse accounted for approximately half of the overlap in corridors and stopover areas, and nearly all overlap on winter ranges, indicating that sage-grouse conservation efforts represent an important step in conserving migratory Mule Deer. Conservation of migratory species presents unique challenges because although overlap with conserved lands may be high, connectivity of the entire route must be maintained as barriers to movement anywhere within the migration corridor could render it unviable. Where Mule Deer habitats overlap with sage-grouse core areas, our results indicate that increased protection is afforded to winter ranges and migration routes within the umbrella of sage-grouse conservation, but this protection is contingent on concentrated developments within core areas not intersecting with high-priority stopovers or corridors, and that the policy in turn does not encourage development on Deer ranges outside of core areas. With the goal of protecting entire migration routes, our analysis highlights areas of potential conservation focus for Mule Deer, which are characterized by high exposure to residential development and use by a large proportion of migrating Deer.
-
Conserving migratory Mule Deer through the umbrella of sage‐grouse
Ecosphere, 2014Co-Authors: Holly E. Copeland, Hall Sawyer, Kevin L. Monteith, David E. Naugle, Amy Pocewicz, N. Graf, Matthew J. KauffmanAbstract:Conserving migratory ungulates in increasingly human-dominated landscapes presents a difficult challenge to land managers and conservation practitioners. Nevertheless, ungulates may receive ancillary benefits from conservation actions designed to protect species of greater conservation priority where their ranges are sympatric. Greater Sage-Grouse (Centrocerus urophasianus), for example, have been proposed as an umbrella species for other sagebrush (Artemesia spp.)-dependent fauna. We examined a landscape where conservation efforts for sage-grouse overlap spatially with Mule Deer (Odocoileus hemionus) to determine whether sage-grouse conservation measures also might protect important Mule Deer migration routes and seasonal ranges. We conducted a spatial analysis to determine what proportion of migration routes, stopover areas, and winter ranges used by Mule Deer were located in areas managed for sage-grouse conservation. Conservation measures overlapped with 66–70% of migration corridors, 74–75% of stopovers, and 52–91% of wintering areas for two Mule Deer populations in the upper Green River Basin of Wyoming. Of those proportions, conservation actions targeted towards sage-grouse accounted for approximately half of the overlap in corridors and stopover areas, and nearly all overlap on winter ranges, indicating that sage-grouse conservation efforts represent an important step in conserving migratory Mule Deer. Conservation of migratory species presents unique challenges because although overlap with conserved lands may be high, connectivity of the entire route must be maintained as barriers to movement anywhere within the migration corridor could render it unviable. Where Mule Deer habitats overlap with sage-grouse core areas, our results indicate that increased protection is afforded to winter ranges and migration routes within the umbrella of sage-grouse conservation, but this protection is contingent on concentrated developments within core areas not intersecting with high-priority stopovers or corridors, and that the policy in turn does not encourage development on Deer ranges outside of core areas. With the goal of protecting entire migration routes, our analysis highlights areas of potential conservation focus for Mule Deer, which are characterized by high exposure to residential development and use by a large proportion of migrating Deer.
-
influence of well pad activity on winter habitat selection patterns of Mule Deer
Journal of Wildlife Management, 2009Co-Authors: Hall Sawyer, Matthew J. Kauffman, Ryan M NielsonAbstract:Abstract Conversion of native winter range into producing gas fields can affect the habitat selection and distribution patterns of Mule Deer (Odocoileus hemionus). Understanding how levels of human activity influence Mule Deer is necessary to evaluate mitigation measures and reduce indirect habitat loss to Mule Deer on winter ranges with natural gas development. We examined how 3 types of well pads with varying levels of vehicle traffic influenced Mule Deer habitat selection in western Wyoming during the winters of 2005–2006 and 2006–2007. Well pad types included producing wells without a liquids gathering system (LGS), producing wells with a LGS, and well pads with active directional drilling. We used 36,699 Global Positioning System locations collected from a sample (n = 31) of adult (>1.5-yr-old) female Mule Deer to model probability of use as a function of traffic level and other habitat covariates. We treated each Deer as the experimental unit and developed a population-level resource selection fun...
-
Mule Deer and pronghorn migration in western wyoming
Wildlife Society Bulletin, 2005Co-Authors: Hall Sawyer, Fred Lindzey, Doug McwhirterAbstract:Abstract Migratory Mule Deer (Odocoileus hemionus) and pronghorn (Antilocapra americana) populations rely on seasonal ranges to meet their annual nutritional and energetic requirements. Because seasonal ranges often occur great distances apart and across a mix of vegetation types and land ownership, maintaining migration corridors to and from these ranges can be difficult, especially if managers do not have detailed information on Mule Deer and pronghorn seasonal movements. We captured, radiomarked, and monitored Mule Deer (n=171) and pronghorn (n=34) in western Wyoming to document seasonal distribution patterns and migration routes. Mule Deer and pronghorn migrated 20–158 km and 116–258 km, respectively, between seasonal ranges. These distances represented the longest recorded migrations for either species. We identified a number of bottlenecks along the migration routes of Mule Deer and pronghorn, but the most critical appeared to be the 1.6-km-wide Trapper's Point bottleneck, which was used by both mul...
W. Finbarr Wilson - One of the best experts on this subject based on the ideXlab platform.
-
Interspecific variation in antipredator behaviour leads to differential vulnerability of Mule Deer and white‐tailed Deer fawns early in life
Journal of Animal Ecology, 2005Co-Authors: Susan Lingle, Sergio M. Pellis, W. Finbarr WilsonAbstract:Summary 1 Ungulates are viewed as being highly susceptible to predation during the initial weeks or months of life. Yet aggressive defence by adult females is common in many ungulates and has the potential to reduce the vulnerability of the young significantly. 2 We observed naturally occurring predatory encounters between coyotes Canis latrans Say and Deer fawns to test the hypothesis that a difference in aggressive defence leads to the differential vulnerability of Mule Deer Odocoileus hemionus Rafinesque and white-tailed Deer O. virginianus Zimmermann fawns in summer, when fawns are 0–14 weeks in age. Whitetail fawns suffer higher levels of coyote predation than do Mule Deer fawns at that time. The two species of Deer are similar in size, but are known to differ in their antipredator behaviour in winter when fawns are older. 3 Coyotes were less likely to attack Mule Deer than whitetail fawns they encountered, and were less likely to kill Mule Deer than whitetail fawns they attacked. 4 The presence of a Mule Deer, but not a whitetail, female with a fawn deterred coyotes from attacking the fawn. Once attacked, fawns of both species were less likely to be killed when females defended them, but Mule Deer females were far more likely to defend fawns. 5 Mule Deer females defended fawns that were not their own offspring, including heterospecific fawns. Mule Deer fawns were more likely to be defended if they had a larger number of females nearby when encountered. These observations raise the possibility that Mule Deer, and even whitetail, fawns may have improved survival in areas with higher densities of Mule Deer females. 6 These results show that higher levels of defence by Mule Deer females reduced the vulnerability of Mule Deer fawns, contributing to the lower predation rates reported for Mule Deer than for whitetail fawns of this age group.
-
Detection and Avoidance of Predators in White-Tailed Deer (Odocoileus virginianus) and Mule Deer (O. hemionus)
Ethology, 2001Co-Authors: Susan Lingle, W. Finbarr WilsonAbstract:In this paper, we investigate the relationship between early detection of predators and predator avoidance in white-tailed Deer (Odocoileus virginianus) and Mule Deer (O. hemionus), two closely related species that differ in their habitat preferences and in their anti-predator behavior. We used observations of coyotes (Canis latrans) hunting Deer to test whether the distance at which white-tails and Mule Deer alerted to coyotes was related to their vulnerability to predation. Coyote encounters with both species were more likely to escalate when Deer alerted at shorter distances. However, coyote encounters with Mule Deer progressed further than encounters with white-tails that alerted at the same distance, and this was not due to species differences in group size or habitat. We then conducted an experiment in which a person approached groups of Deer to compare the detection abilities and the form of alert response for white-tails and Mule Deer, and for age groups within each species. Mule Deer alerted to the approacher at longer distances than white-tails, even after controlling for variables that were potentially confounding. Adult females of both species alerted sooner than conspecific juveniles. Mule Deer almost always looked directly at the approacher as their initial response, whereas white-tails were more likely to flee or to look in another direction with no indication that they pinpointed the approacher during the trial. Mule Deer may have evolved the ability to detect predators earlier than white-tails as an adaptation to their more open habitats, or because they need more time to coordinate subsequent anti-predator defenses.
Finbarr W Wilson - One of the best experts on this subject based on the ideXlab platform.
-
interspecific variation in antipredator behaviour leads to differential vulnerability of Mule Deer and white tailed Deer fawns early in life
Journal of Animal Ecology, 2005Co-Authors: Susan Lingle, Sergio M. Pellis, Finbarr W WilsonAbstract:Summary 1 Ungulates are viewed as being highly susceptible to predation during the initial weeks or months of life. Yet aggressive defence by adult females is common in many ungulates and has the potential to reduce the vulnerability of the young significantly. 2 We observed naturally occurring predatory encounters between coyotes Canis latrans Say and Deer fawns to test the hypothesis that a difference in aggressive defence leads to the differential vulnerability of Mule Deer Odocoileus hemionus Rafinesque and white-tailed Deer O. virginianus Zimmermann fawns in summer, when fawns are 0–14 weeks in age. Whitetail fawns suffer higher levels of coyote predation than do Mule Deer fawns at that time. The two species of Deer are similar in size, but are known to differ in their antipredator behaviour in winter when fawns are older. 3 Coyotes were less likely to attack Mule Deer than whitetail fawns they encountered, and were less likely to kill Mule Deer than whitetail fawns they attacked. 4 The presence of a Mule Deer, but not a whitetail, female with a fawn deterred coyotes from attacking the fawn. Once attacked, fawns of both species were less likely to be killed when females defended them, but Mule Deer females were far more likely to defend fawns. 5 Mule Deer females defended fawns that were not their own offspring, including heterospecific fawns. Mule Deer fawns were more likely to be defended if they had a larger number of females nearby when encountered. These observations raise the possibility that Mule Deer, and even whitetail, fawns may have improved survival in areas with higher densities of Mule Deer females. 6 These results show that higher levels of defence by Mule Deer females reduced the vulnerability of Mule Deer fawns, contributing to the lower predation rates reported for Mule Deer than for whitetail fawns of this age group.