15 results on '"Kerry M. Murphy"'
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2. Prey Selection by Cougars and Wolves
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Douglas W. Smith, Kerry M. Murphy, Toni K. Ruth, Maurice G. Hornocker, and Polly C. Buotte
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Zoology ,Biology ,Selection (genetic algorithm) ,Predation - Published
- 2019
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3. Rates of Predation
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Toni K. Ruth, Kerry M. Murphy, Polly C. Buotte, and Maurice G. Hornocker
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Ecology ,Biology ,Predation - Published
- 2019
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4. Linking resource selection and mortality modeling for population estimation of mountain lions in Montana
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Mark Hebblewhite, Michael S. Mitchell, Kyran Kunkel, James Williams, Toni K. Ruth, Kerry M. Murphy, Rich DeSimone, Justin A. Gude, David C. Choate, Marc R. Matchett, and Hugh S. Robinson
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education.field_of_study ,biology ,Ecology ,Ecological Modeling ,Population ,Metapopulation ,Leslie matrix ,biology.organism_classification ,Population density ,Fishery ,Population decline ,Geography ,Mountain lion ,Biological dispersal ,Population growth ,education - Abstract
a b s t r a c t To be most effective, the scale of wildlife management practices should match the range of a particular species' movements. For this reason, combined with our inability to rigorously or regularly census moun- tain lion populations, several authors have suggested that mountain lions be managed in a source-sink or metapopulation framework. We used a combination of resource selection functions, mortality estima- tion, and dispersal modeling to estimate cougar population levels in Montana statewide and potential population level effects of planned harvest levels. Between 1980 and 2012, 236 independent mountain lions were collared and monitored for research in Montana. From these data we used 18,695 GPS loca- tions collected during winter from 85 animals to develop a resource selection function (RSF), and 11,726 VHF and GPS locations from 142 animals along with the locations of 6343 mountain lions harvested from 1988-2011 to validate the RSF model. Our RSF model validated well in all portions of the State, although it appeared to perform better in Montana Fish, Wildlife and Parks (MFWP) Regions 1, 2, 4 and 6, than in Regions 3, 5, and 7. Our mean RSF based population estimate for the total population (kittens, juveniles, and adults) of mountain lions in Montana in 2005 was 3926, with almost 25% of the entire population in MFWP Region 1. Estimates based on a high and low reference population estimates produce a possible range of 2784 to 5156 mountain lions statewide. Based on a range of possible survival rates we estimated the mountain lion population in Montana to be stable to slightly increasing between 2005 and 2010 with lambda ranging from 0.999 (SD = 0.05) to 1.02 (SD = 0.03). We believe these population growth rates to be a conservative estimate of true population growth. Our model suggests that proposed changes to female harvest quotas for 2013-2015 will result in an annual statewide population decline of 3% and shows that, due to reduced dispersal, changes to harvest in one management unit may affect population growth in neighboring units where smaller or even no changes were made. Uncertainty regarding dis- persal levels and initial population density may have a significant effect on predictions at a management unit scale (i.e. 2000 km 2 ), while at a regional scale (i.e. 50,000 km 2
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- 2015
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5. Human-caused mortality influences spatial population dynamics: Pumas in landscapes with varying mortality risks
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Rich DeSimone, Kerry M. Murphy, Toni K. Ruth, Daniel H. Pletscher, Howard Quigley, Michael S. Mitchell, Jesse Newby, and L. Scott Mills
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education.field_of_study ,National park ,Ecology ,Applied ecology ,Population ,Metapopulation ,Geography ,Biological dispersal ,Population growth ,Ecosystem ,Vital rates ,education ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Abstract
An understanding of how stressors affect dispersal attributes and the contribution of local populations to multi-population dynamics are of immediate value to basic and applied ecology. Puma (Puma concolor) populations are expected to be influenced by inter-population movements and susceptible to humaninduced source–sink dynamics. Using long-term datasets we quantified the contribution of two puma populations to operationally define them as sources or sinks. The puma population in the Northern Greater Yellowstone Ecosystem (NGYE) was largely insulated from human-induced mortality by Yellowstone National Park. Pumas in the western Montana Garnet Mountain system were exposed to greater human-induced mortality, which changed over the study due to the closure of a 915 km 2 area to hunting. The NGYE’s population growth depended on inter-population movements, as did its ability to act as a source to the larger region. The heavily hunted Garnet area was a sink with a declining population until the hunting closure, after which it became a source with positive intrinsic growth and a 16� increase in emigration. We also examined the spatial and temporal characteristics of individual dispersal attributes (emigration, dispersal distance, establishment success) of subadult pumas (N = 126). Human-caused mortality was found to negatively impact all three dispersal components. Our results demonstrate the influence of human-induced mortality on not only within population vital rates, but also inter-population vital rates, affecting the magnitude and mechanisms of local population’s contribution to the larger metapopulation.
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- 2013
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6. Cougar survival and source-sink structure on Greater Yellowstone's Northern Range
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Toni K. Ruth, Howard Quigley, Mark A. Haroldson, Kerry M. Murphy, Polly C. Buotte, and Maurice G. Hornocker
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Biomass (ecology) ,Ungulate ,Ecology ,biology ,Range (biology) ,National park ,Population size ,Wildlife ,biology.organism_classification ,Canis ,General Earth and Planetary Sciences ,Population study ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation ,General Environmental Science - Abstract
We studied survival and causes of mortality of radiocollared cougars (Puma concolor) on the Greater Yellowstone Northern Range (GYNR) prior to (1987-1994) and after wolf (Canis lupus) reintro- duction (1998-2005) and evaluated temporal, spatial, and environmental factors that explain variation in adult, subadult, and kitten survival. Using Program MARK and multimodel inference, we modeled cougar survival based on demographic status, season, and landscape attributes. Our best models for adult and independent subadults indicated that females survived better than males and survival increased with age until cougars reached older ages. Lower elevations and increasing density of roads, particularly in areas open to cougar hunting north of Yellowstone National Park (YNP), increased mortality risks for cougars on the GYNR. Indices of ungulate biomass, cougar and wolf population size, winter severity, rainfall, and individual characteristics such as the presence of dependent young, age class, and use of Park or Wilderness were not important predictors of survival. Kitten survival increased with age, was lower during winter, increased with increasing minimum estimates of elk calf biomass, and increased with increasing density of adult male cougars. Using our best model, we mapped adult cougar survival on the GYNR landscape. Results of receiver operating characteristic (ROC) analysis indicated a good model fit for both female (area under the curve (AUC) ¼ 0.81, 95%CI ¼ 0.70-0.92, n ¼ 35 locations) and male cougars (AUC ¼ 0.84, 95%CI ¼ 0.74- 0.94, n ¼ 49 locations) relative to hunter harvest locations in our study area. Using minimum estimates of survival necessary to sustain the study population, we developed a source-sink surface and we identify several measures that resource management agencies can take to enhance cougar population management based on a source-sink strategy. 2011 The Wildlife Society.
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- 2011
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7. Distribution and Abundance of Snowshoe Hares in Yellowstone National Park
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Karen E. Hodges, L. Scott Mills, and Kerry M. Murphy
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Pinus contorta ,Ecology ,biology ,National park ,Range (biology) ,Snowshoe hare ,biology.organism_classification ,Geography ,Boreal ,Seral community ,Abundance (ecology) ,Threatened species ,Genetics ,Animal Science and Zoology ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation - Abstract
Snowshoe hares (Lepus americanus) are widespread in boreal and montane forests of North America, vary in their temporal dynamics, and are major drivers in their food webs. In Yellowstone National Park, Wyoming, hare abundance, distribution, and temporal dynamics are unknown, yet Yellowstone contains a large area within their southern range that is relatively unfragmented by human activities. The 1988 Yellowstone fires have led to extensive regenerating stands, a seral condition that elsewhere supports relatively high numbers of hares. To examine snowshoe hare dynamics in the park from 2002 to 2007, we surveyed stands within 7 cover types and estimated abundance for a subset of sites. Both livetrapping data and fecal pellet count surveys showed that snowshoe hares are rare in Yellowstone. More than 36% of surveyed stands did not support any hares. Mature forest cover types were more likely to have hares than were stands regenerating after the 1988 fires, but very few stands supported high numbers; 96% of stands had ,0.5 hares/ha. Three stands that burned in 2003 had hares before the fire, but none afterward. Hare numbers fluctuated modestly over time, but patterns were not indicative of a cycle. Taken altogether, our results indicate that snowshoe hares in Yellowstone are rare, patchily distributed, and apparently acyclic, important findings both for understanding hare dynamics and for implications for the Yellowstone food web that includes the federally Threatened Canada lynx (Lynx canadensis).
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- 2009
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8. Examining effects of persistent retroviral infection on fitness and pathogen susceptibility in a natural feline host
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Toni K. Ruth, Mary Poss, Roman Biek, Kerry M. Murphy, and Charles R. Anderson
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Host (biology) ,Ecology ,Retroviral infection ,Animal Science and Zoology ,Biology ,Pathogen ,Virology ,Ecology, Evolution, Behavior and Systematics ,Natural (archaeology) ,Virus - Abstract
Many animal populations carry endemic (i.e., permanently present) viruses but few studies have assessed the demographic consequences of these infections under natural conditions. We examined the effects of chronic infection with FIVPco, a feline retrovirus, on the fitness and pathogen susceptibility of its natural host, the cougar (Puma concolor (L., 1771)), in the wild. Based on data obtained through intensive monitoring of 160 cougars from two populations, we estimated survival and different measures of host fecundity of infected and uninfected individuals. In addition, we used serological data collected from 207 cougars to test whether FIVPcopredisposes individuals to a higher probability of infection with other pathogens. We found no evidence for an overall reduction in survival due to FIVPcowhen accounting for other sources of demographic variation (age, sex, and population). There was a consistent but nonsignificant trend towards poorer reproductive performance in FIVPco-infected females. We found no serological evidence for a higher probability of secondary infections associated with FIVPco. Overall, these results support the premise that chronic FIVPcoinfection is asymptomatic in its natural cougar host, probably because of a long evolutionary association between virus and host. However, results of stochastic simulations indicate that only larger reductions in annual survival (>20%) can be excluded with confidence. Also, the possibility of a so far unrecognized cost of FIVPcoinfection on cougar fecundity remains.
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- 2006
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9. WINTER PREY SELECTION AND ESTIMATION OF WOLF KILL RATES IN YELLOWSTONE NATIONAL PARK, 1995–2000
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Douglas W. Smith, Debra S. Guernsey, Thomas D. Drummer, Kerry M. Murphy, and Shaney B. Evans
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Estimation ,Ecology ,biology ,Kill rate ,National park ,Late winter ,biology.organism_classification ,Predation ,Canis ,Geography ,Recovery rate ,General Earth and Planetary Sciences ,Ecosystem ,Ecology, Evolution, Behavior and Systematics ,Nature and Landscape Conservation ,General Environmental Science - Abstract
Wolf (Canis lupus) impacts on prey are a central post-wolf-reintroduction issue in the greater Yellowstone ecosystem (GYE) of the western United States. Further, estimates of wolf kill rates, used to understand these impacts, can be biased due to unrecovered kills. In Yellowstone National Park (YNP), visibility of wolves allowed us to combine independent aerial and ground observations and use a double-count method to estimate the probability of recovering kills. We consequently used these data to adjust estimates of wolf kill rates. We conducted monitoring annually from 1995 to 2000 during 2 30-day periods in early (15 Nov–14 Dec) and late winter (Mar). Estimated recovery rates of wolf kills for ground and aerial crews were 50% and 45%, respectively, although we determined that this varied by location (distance from road) and possibly age (calf or adult) of the kill. The estimated combined recovery rate was 73%. Estimated wolf kill rates were higher in late winter (2.2 kills/wolf/month) compared ...
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- 2004
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10. Trophic facilitation by introduced top predators: grey wolf subsidies to scavengers in Yellowstone National Park
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Douglas W. Smith, Christopher C. Wilmers, Wayne M. Getz, Kerry M. Murphy, and Robert L. Crabtree
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Canis ,Ecology ,Foraging ,Animal Science and Zoology ,Carrion ,Biology ,biology.organism_classification ,Keystone species ,Ecology, Evolution, Behavior and Systematics ,Predation ,Optimal foraging theory ,Apex predator ,Trophic level - Abstract
Summary 1. The reintroduction of grey wolves Canis lupus (L.) to Yellowstone National Park provides a natural experiment in which to study the effects of a keystone predator on ecosystem function. 2. Grey wolves often provision scavengers with carrion by partially consuming their prey. 3. In order to examine how grey wolf foraging behaviour influences the availability of carrion to scavengers, we observed consumption of 57 wolf-killed elk Cervus elaphus (L.) and determined the percentage of edible biomass eaten by wolves from each carcass. 4. We found that the percentage of a carcass consumed by wolves increases as snow depth decreases and the ratio of wolf pack size to prey size and distance to the road increases. In addition, wolf packs of intermediate size provide the most carrion to scavengers. 5. Applying linear regression models to the years prior to reintroduction, we calculate carrion biomass availability had wolves been present, and contrast this to a previously published index of carrion availability. Our results demonstrate that wolves increase the time period over which carrion is available, and change the variability in scavenge from a late winter pulse dependent primarily on abiotic environmental conditions to one that is relatively constant across the winter and primarily dependent on wolf demographics. Wolves also decrease the year-to-year and month-to-month variation in carrion availability. 6. By transferring the availability of carrion from the highly productive late winter, to the less productive early winter and from highly productive years to less productive ones, wolves provide a temporal subsidy to scavengers.
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- 2003
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11. Population size estimation in Yellowstone wolves with error‐prone noninvasive microsatellite genotypes
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Janet Zeigle, Kerry M. Murphy, Douglas W. Smith, Jay J. Rotella, Jennifer L. Sands, Göran Spong, Lawrence Joe, and Scott Creel
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Wyoming ,Conservation of Natural Resources ,Population ,Biology ,Polymerase Chain Reaction ,Population density ,law.invention ,law ,Genotype ,Genetics ,Animals ,Allele ,education ,Genotyping ,Alleles ,Ecology, Evolution, Behavior and Systematics ,Polymerase chain reaction ,Population Density ,education.field_of_study ,Wolves ,Population size ,Research Design ,Evolutionary biology ,Microsatellite ,Electrophoresis, Polyacrylamide Gel ,Microsatellite Repeats - Abstract
Determining population sizes can be difficult, but is essential for conservation. By counting distinct microsatellite genotypes, DNA from noninvasive samples (hair, faeces) allows estimation of population size. Problems arise because genotypes from noninvasive samples are error-prone, but genotyping errors can be reduced by multiple polymerase chain reaction (PCR). For faecal genotypes from wolves in Yellowstone National Park, error rates varied substantially among samples, often above the 'worst-case threshold' suggested by simulation. Consequently, a substantial proportion of multilocus genotypes held one or more errors, despite multiple PCR. These genotyping errors created several genotypes per individual and caused overestimation (up to 5.5-fold) of population size. We propose a 'matching approach' to eliminate this overestimation bias.
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- 2003
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12. Ovarian Function after Uterine Artery Embolization for Leiomyomata: Assessment with Use of Serum Follicle Stimulating Hormone Assay
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Antoinette R. Roth, Kerry M. Murphy-Skrzyniarz, James B. Spies, and Sheila M. Gonsalves
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Adult ,medicine.medical_specialty ,media_common.quotation_subject ,medicine.medical_treatment ,Physiology ,Follicle-stimulating hormone ,Basal (phylogenetics) ,Uterine artery embolization ,Humans ,Medicine ,Radiology, Nuclear Medicine and imaging ,Menstrual cycle ,media_common ,Gynecology ,Analysis of Variance ,Chi-Square Distribution ,Leiomyoma ,business.industry ,Ovary ,Uterus ,Uterus neoplasm ,Repeated measures design ,Arteries ,Middle Aged ,Embolization, Therapeutic ,Treatment Outcome ,Uterine Neoplasms ,Female ,Analysis of variance ,Follicle Stimulating Hormone ,Cardiology and Cardiovascular Medicine ,business ,Chi-squared distribution - Abstract
PURPOSE To determine if uterine artery embolization (UAE) for leiomyomata causes a change in ovarian function as measured by serial basal follicle stimulating hormone (FSH) assay. MATERIALS AND METHODS Sixty-three patients undergoing UAE for symptomatic leiomyomata had blood samples obtained on day 3 of a menstrual cycle before UAE and on day 3 during menstrual cycles 3 and 6 months after treatment. Analysis of variance was used to detect differences in FSH levels among age groups at each interval. Repeated measures analysis of variance was used to determine if individual mean change occurred for the group as a whole and for each age group. Onset of new menopausal symptoms was compared between groups with use of the x 2 test. RESULTS There was no significant change in basal FSH levels for the group as a whole ( P = .16), but there was a statistically significant difference when age groups were compared ( P = .03). Individual change of >2 SD from baseline mean FSH level occurred at 6 months in seven patients, all 45–50 years of age. Four of these patients (15% of patients over age 44) had FSH levels increase to more than 20 IU/L. x 2 analysis did not reveal any difference among the groups studied in the onset of menopausal symptoms. CONCLUSIONS Most patients had no change in ovarian function as measured by basal FSH after UAE. For patients aged 45 or older, there is approximately a 15% chance of an increase in basal FSH into the perimenopausal range.
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- 2001
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13. Genetic consequences of sex-biased dispersal in a solitary carnivore: Yellowstone cougars
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Michael K. Schwartz, Naomi Akamine, Toni K. Ruth, Roman Biek, Kerry M. Murphy, and Mary Poss
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Male ,Reproductive success ,National park ,Ecology ,Population Dynamics ,Zoology ,Biology ,Agricultural and Biological Sciences (miscellaneous) ,United States ,Sex Factors ,Trait ,Biological dispersal ,Inbreeding avoidance ,Animals ,Philopatry ,Female ,Inbreeding ,Puma ,Carnivore ,General Agricultural and Biological Sciences ,Research Article - Abstract
Male-biased dispersal is a common trait in mammals, including carnivores, but its genetic consequences at the population level have been rarely considered for solitary species. We used long-term genetic data from cougars ( Puma concolor ) in and around Yellowstone National Park to test predictions based on differences in dispersal behaviour among males and females. Consistent with frequent long-distance dispersal of males, we found support for our prediction of less than expected allele sharing in pair-wise comparisons. In contrast, female residents present at the same time and females separated by few generations failed to share more alleles than expected, contrary to our predictions based on limited female dispersal. However, we find that genetic contributions of females with higher reproductive success were still noticeable in subsequent generations, consistent with female offspring showing fidelity to their natal area. These results highlight the importance of male dispersal for inbreeding avoidance, but do not indicate that short-distance dispersal or philopatry in female cougars results in spatial clustering of related individuals.
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- 2006
14. Factors associated with pathogen seroprevalence and infection in Rocky Mountain cougars
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Toni K. Ruth, Roman Biek, Mark K. Johnson, Colin Gillin, Maurice G. Hornocker, Richard DeSimone, Kerry M. Murphy, Mary Poss, Rachel Gray, and Charles R. Anderson
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Male ,Feline immunodeficiency virus ,Feline coronavirus ,Yersinia pestis ,animal diseases ,viruses ,Animals, Wild ,Immunodeficiency Virus, Feline ,medicine.disease_cause ,Antibodies, Viral ,Virus ,Parvovirus ,Sex Factors ,Risk Factors ,Seroepidemiologic Studies ,medicine ,Seroprevalence ,Animals ,Coronavirus, Feline ,Distemper Virus, Canine ,Ecology, Evolution, Behavior and Systematics ,Herpesviridae ,Coronavirus ,Feline calicivirus ,Plague ,Ecology ,biology ,Canine distemper ,Transmission (medicine) ,Age Factors ,virus diseases ,biology.organism_classification ,medicine.disease ,Virology ,Antibodies, Bacterial ,United States ,Virus Diseases ,Immunology ,Female ,Puma ,Calicivirus, Feline - Abstract
Serological and genetic material collected over 15 years (1990-2004) from 207 cougars (Puma concolor) in four populations in the Rocky Mountains were examined for evidence of current or prior exposure to feline immunodeficiency virus (FIV), feline parvovirus (FPV), feline coronavirus (FCoV), feline calicivirus (FCV), canine distemper virus (CDV), feline herpesvirus (FHV), and Yersinia pestis. Serologic data were analyzed for annual variation in seroconversions to assess whether these pathogens are epidemic or endemic in cougars, and to determine whether family membership, age, sex, or location influence risk of exposure. FIV and FPV were clearly endemic in the studied populations, whereas exposure to FCoV, FCV, CDV, and Y. pestis was more sporadic. No evidence was found for FHV. Age was the most consistent predictor of increased exposure risk, often with no other important factors emerging. Evidence for transmission within family groups was limited to FIV and FCoV, whereas some indication for host sex affecting exposure probability was found for FIV and Y. pestis. Overall, cougar populations exhibited few differences in terms of pathogen presence and prevalence, suggesting the presence of similar risk factors throughout the study region.
- Published
- 2006
15. Winter Severity and Wolf Predation on a Formerly Wolf-Free Elk Herd
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L. David Mech, Kerry M. Murphy, Douglas W. Smith, and Daniel R. MacNulty
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Ecology ,biology ,National park ,animal diseases ,biology.organism_classification ,Predation ,Canis ,Animal science ,Repoblación ,Herd ,General Earth and Planetary Sciences ,Cervus elaphus ,Predator ,Ecology, Evolution, Behavior and Systematics ,Sex ratio ,Nature and Landscape Conservation ,General Environmental Science - Abstract
We studied wolf (Canis lupus) predation on elk (Cervus elaphus) in Yellowstone National Park from 17 March to 15 April 1997 (severe winter conditions) and from 2 to 31 March 1998 (mild winter conditions) 2-3 years after wolves were reintroduced to the park. Elk composed 91% of 117 kills. Data comparisons for 1997 versus 1998 were: hunting success rate, 26% versus 15%; kill rate, 17.1 kg/wolf/day versus 6.1; percent of kill consumed in first day 7 versus 86; percent femur marrow fat of adult kills, 27 versus 70; calf:adult ratios of kills, 2:33 versus 17:23; sex ratio of kills, 14M:19F versus 17M:6F; mean age of elk killed, males 6.1 years, females 15.2 versus males, 4.8, females 13.0. Winter severity influenced the wolf-elk relationship more than the naivete of the elk herd to predation by wolves.
- Published
- 2001
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