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Spatial Ecology of Coyotes and Cougars: Understanding the Influence of Multiple Prey on the Spatial Interactions of Two PredatorsMahoney, Peter J. 01 May 2017 (has links)
The extent to which predators regulate prey populations remains a subject of debate. Yet, when predator control is employed as a management strategy, it is often assumed that predators can and do regulate prey populations. From 2011 through 2015, I monitored the demography and space use of coyotes (Canis latrans) and cougars (Puma concolor) on Monroe Mountain in Fishlake National Forest, Utah as part of a larger collaboration investigating the impacts of coyote aerial control on mule deer (Odocoileus hemionus) neonate survival. My primary objective was to assess the impacts of anthropogenic regulation on the respective populations and identify any cascading effects relevant to mule deer management. To meet this objective, I established a monitoring program for both predators by deploying radio-telemetry collars (VHF and GPS) on each, documented predation events, established surveys for small mammals and lagomorphs to monitor primary prey populations during deer parturition (June – August), and collected data on the location and demographic composition of winter-removed coyotes. I analyzed these data primarily in a community-based, animal movement and resource selection framework permitting the integration of data from multiple sources. When evaluating coyote aerial removal as a management strategy, I identified a spatial dependency in the ability to match removals with indices of deer recruitment as Wildlife Services Operations personnel were primarily limited by terrain and tree cover. Thus, matching treatment with deer fawning was highly variable with only a small number of sites where removals were effective. In addition, I found that coyotes selected for sites with the highest densities of lagomorphs while avoiding areas with a high probability of encountering cougars. Coyotes did not select for mule deer fawning sites, although individual coyotes that occupied resource-poor home ranges were more likely to do so. Cougars strongly selected for mule deer high use areas throughout much of the year, only switching to elk (Cervus elaphus) during the cougar harvest season (i.e., winter). Data from cougar kill site investigations match the observed patterns in cougar space use. My results suggest that predator-prey processes are multi-dimensional and dynamic through time, which likely contribute to the lack of resolution regarding the efficacy of predator control and the regulatory potential of predators in general.
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Surveillance for chronic wasting disease and other infectious agents in mule deer (<i>Odocoileus hemionus</i>) and white-tailed deer (<i>Odocoileus virginianus</i>) in southern SaskatchewanFernando, Champika 25 February 2011
Chronic wasting disease (CWD) was detected in Saskatchewan wild deer populations in 2000 which prompted disease management actions consisting of population reduction. Little is known about population structure, health status, interactions or movement patterns of deer in Saskatchewan and these factors are important in designing a management program for CWD. As part of an ongoing study on deer movement patterns of wild deer in southern Saskatchewan, a survey was conducted to: 1) determine prevalence of CWD and selected infectious agents in mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus), and 2) identify infectious agents which could be used as a surrogate measure of the effectiveness of the adopted CWD management strategies. Tonsil biopsies, feces and blood were collected from 254 mule deer and 43 white-tailed deer during winters of 2006, 2007 and 2008. Immunohistochemical staining of tonsil biopsies for CWD revealed a prevalence of 2.4% (6/249) in mule deer and 0% (0/43) in white-tailed deer. Parasitological investigation of 253 fecal samples from mule deer identified eggs of nematodes in the superfamily Trichostrongyloidea (29.2%); and parasitic stages of the following genera: Nematodirus (7.1%), Skrjabinema (14.3%), Trichuris (0.8%), Moniezia (16.2%), Thysanosoma (12.2%), Orthostrongylus (35.2%), Eimeria (13.4%) and Giardia (0%, 0/137). A similar investigation of 42 white-tailed deer fecal samples identified parasitic stages of nematodes in the super family Trichostrongyloidea (4.8%) and in genera of Orthostrongylus (2.4%), Moniezia (2.4%) and Eimeria (2.4%). Dorsal-spined larvae were detected in 2.4% of the white-tailed deer fecal samples. In serum samples from 253 mule deer, antibodies (Ab) were detected against bovine herpesvirus1 (BoHV-1) (34.8%), parainfluenza-3 (PI-3) (56.5%), bovine virus diarrhoea virus (BVDV-1) (30.8%) and Neospora caninum (15.4%, 36/245). In serum samples from 40 white-tailed deer, Ab to BoHV-1(32.5%), PI-3 (35%), BVD-1 (12.5%) and Neospora caninum (20.5%, 8/39) was detected.
Based on relative host specificity, moderate prevalence and horizontal routes of transmission, herpesvirus, parainfluenza 3, Eimeria and Skrjabinema were identified as infectious agents which could potentially be used to evaluate the effectiveness of disease management strategies, which may in turn predict the response of CWD to these same strategies. Using polymerase chain reaction (PCR) a herpesvirus was detected, in 42.1% (40/95) of retropharyngeal lymph nodes from hunter-submitted mule deer and white-tailed deer heads from Saskatchewan in 2007. DNA sequences of the partial DNA polymerase gene from this virus were 98 - 100% identical to mule deer lymphotropic herpesvirus (mule deer-LHV). A 3.6 kb contiguous sequence of mule deer-LHV genome was generated by genome walking (GenBank Accession number: HM014314). Use of a mule deer-LHV-specific PCR on buffy coat samples collected during winters of 2007 and 2008, detected mule deer-LHV in 42.1% (67/158) of mule deer and 33.3% (8/24) of white-tailed deer. Very little DNA sequence diversity in the partial sequences of glycoprotein B (gB) gene and the intergenic spacer regions between DPOL and gB gene of mule deer-LHV was observed among deer from different wildlife management zones.
Mule deer-LHV is also a potential marker for evaluating the effectiveness of disease management activities because of its moderate prevalence, host specificity, ease of sample collection and the availability of a rapid and low-cost method for its detection. A variable region of the mule deer-LHV genome needs to be identified if this virus to be used as an inferential tool for studying host population structure.
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Surveillance for chronic wasting disease and other infectious agents in mule deer (<i>Odocoileus hemionus</i>) and white-tailed deer (<i>Odocoileus virginianus</i>) in southern SaskatchewanFernando, Champika 25 February 2011 (has links)
Chronic wasting disease (CWD) was detected in Saskatchewan wild deer populations in 2000 which prompted disease management actions consisting of population reduction. Little is known about population structure, health status, interactions or movement patterns of deer in Saskatchewan and these factors are important in designing a management program for CWD. As part of an ongoing study on deer movement patterns of wild deer in southern Saskatchewan, a survey was conducted to: 1) determine prevalence of CWD and selected infectious agents in mule deer (Odocoileus hemionus) and white-tailed deer (Odocoileus virginianus), and 2) identify infectious agents which could be used as a surrogate measure of the effectiveness of the adopted CWD management strategies. Tonsil biopsies, feces and blood were collected from 254 mule deer and 43 white-tailed deer during winters of 2006, 2007 and 2008. Immunohistochemical staining of tonsil biopsies for CWD revealed a prevalence of 2.4% (6/249) in mule deer and 0% (0/43) in white-tailed deer. Parasitological investigation of 253 fecal samples from mule deer identified eggs of nematodes in the superfamily Trichostrongyloidea (29.2%); and parasitic stages of the following genera: Nematodirus (7.1%), Skrjabinema (14.3%), Trichuris (0.8%), Moniezia (16.2%), Thysanosoma (12.2%), Orthostrongylus (35.2%), Eimeria (13.4%) and Giardia (0%, 0/137). A similar investigation of 42 white-tailed deer fecal samples identified parasitic stages of nematodes in the super family Trichostrongyloidea (4.8%) and in genera of Orthostrongylus (2.4%), Moniezia (2.4%) and Eimeria (2.4%). Dorsal-spined larvae were detected in 2.4% of the white-tailed deer fecal samples. In serum samples from 253 mule deer, antibodies (Ab) were detected against bovine herpesvirus1 (BoHV-1) (34.8%), parainfluenza-3 (PI-3) (56.5%), bovine virus diarrhoea virus (BVDV-1) (30.8%) and Neospora caninum (15.4%, 36/245). In serum samples from 40 white-tailed deer, Ab to BoHV-1(32.5%), PI-3 (35%), BVD-1 (12.5%) and Neospora caninum (20.5%, 8/39) was detected.
Based on relative host specificity, moderate prevalence and horizontal routes of transmission, herpesvirus, parainfluenza 3, Eimeria and Skrjabinema were identified as infectious agents which could potentially be used to evaluate the effectiveness of disease management strategies, which may in turn predict the response of CWD to these same strategies. Using polymerase chain reaction (PCR) a herpesvirus was detected, in 42.1% (40/95) of retropharyngeal lymph nodes from hunter-submitted mule deer and white-tailed deer heads from Saskatchewan in 2007. DNA sequences of the partial DNA polymerase gene from this virus were 98 - 100% identical to mule deer lymphotropic herpesvirus (mule deer-LHV). A 3.6 kb contiguous sequence of mule deer-LHV genome was generated by genome walking (GenBank Accession number: HM014314). Use of a mule deer-LHV-specific PCR on buffy coat samples collected during winters of 2007 and 2008, detected mule deer-LHV in 42.1% (67/158) of mule deer and 33.3% (8/24) of white-tailed deer. Very little DNA sequence diversity in the partial sequences of glycoprotein B (gB) gene and the intergenic spacer regions between DPOL and gB gene of mule deer-LHV was observed among deer from different wildlife management zones.
Mule deer-LHV is also a potential marker for evaluating the effectiveness of disease management activities because of its moderate prevalence, host specificity, ease of sample collection and the availability of a rapid and low-cost method for its detection. A variable region of the mule deer-LHV genome needs to be identified if this virus to be used as an inferential tool for studying host population structure.
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Influence of Release Timing on Survival and Movements of Translocated Mule Deer (<em>Odocoileus hemionus</em>) in UtahSmedley, David C. 01 June 2016 (has links)
Translocation of wildlife has become common practice for wildlife managers charged with management of animals on increasingly modified landscapes. Translocation can be used to reduce population density in the source area, supplement existing populations, reestablish extirpated populations, and establish new populations. Mule deer (Odocoileus hemionus) are a species of great interest to the public in western North America. Although translocations have been used to manage mule deer, very little has been done to document the outcomes of this management practice. The purpose of this research was to evaluate movement, site fidelity, space use, and survival of translocated mule deer in relation to the timing of release (early versus late winter) and to provide managers with information useful in judging the relative value of translocation as a management strategy for this species. We captured 102 mule deer in January and March 2013 and translocated them from winter range near Parowan, UT, to winter range along the Pahvant Mountain Range near Holden, UT (approximately 144 km north of the capture location). Each deer was fitted with a radio transmitter (21 GPS collars, 81 VHF collars) prior to release to document outcomes. In January 2013 and 2014 we also captured and marked a total of 70 resident deer (non-translocated deer; 9 GPS collars, 61 VHF collars) to serve as a reference group within our study area. Following release, we monitored deer weekly through March 2015. We found that translocated deer had lower annual survival rates than resident deer during the first year following release, but similar annual survival rates to resident deer during the second year following release. Additionally, we found that age strongly influenced the survival of translocated deer; young deer (e.g., 2.5 year olds) were more than twice as likely to survive the initial year following translocation than old deer (e.g., 7.5 year olds). We also found that translocated deer had larger home ranges compared to resident deer during the first and second years following release. However, the average size of translocated deer home ranges decreased from year 1 to year 2 following release. Despite these large home ranges and extended movements during the summer months, most surviving deer (96 %) returned (within < 30 km) to winter range where they were released. We found no difference in movement, site fidelity, or survival for transplanted deer released in January and March. Based on our findings, wildlife managers that elect to translocate mule deer should not expect a difference in survival between early and late winter releases, but will likely see high site fidelity, higher survival rates during the second year following translocation (compared to the first year), and higher survival rates for younger deer compared to older deer.
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Efficacy of Translocation as a Management Tool for Urban Mule Deer in UtahHoward, Channing R. 01 December 2018 (has links)
An increase in urbanization in the United States has led to an increase in human-wildlife interactions with deer (Odocoileus spp.) which have been able to adapt and thrive in these urban environments. In Utah, urbanization has occurred along the Wasatch Front which was once traditional mule deer (Odocoileus hemionus) winter range habitat. This urban expansion coupled with an increasing use of these urban areas by mule deer, have led to increasing conflicts with deer. Overabundant urban deer have led to increased concerns over safety from deer-vehicle collisions, and damage to personal property including gardens and landscaping. Lethal methods of urban deer control, such as controlled hunting or sharpshooting have proven prohibitive due to perceptions of safety or local ordinance prohibiting discharge of weapons. Managers have thus begun to investigate translocation as an alternative method of reducing deer and deer related problems.
I evaluated the efficacy of translocation by determining factors influencing the survival of translocated urban mule deer, reporting the costs per deer of translocation, and determining change in public attitudes toward urban deer after 2 years of removing deer via translocation. Results indicate that translocated urban deer survival is reduced by age and injuries, and that male survival is much lower than that of females, however survival was higher among deer that made it into the second year post-release. Overall survival of translocated urban deer is still lower than the average statewide survival for wild mule deer in Utah. Public perception of the amount of deer decreased slightly after 2 years of deer removals and attitudes were influenced by the severity of damage to gardens and landscaping.
This research can provide managers with information on the hazards influencing survival of translocated urban mule deer as well as the costs associated with implementing and maintaining a translocation program to mitigate urban mule deer problems. It can also provide managers with information on the social impacts such a program has on the attitudes and perceptions of urban deer.
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Development of an Innovative Statewide Population Monitoring Program for Mule DeerBernales, Heather H. 01 May 2010 (has links)
Monitoring population trend and estimating vital demographic parameters are essential for effective management of a mule deer (Odocoileus hemionus) population. Because of financial constraints, many wildlife agencies use computer models to obtain indirect indices of population size and trend as an alternative to annual field-based estimates of population size. These models are based primarily on herd composition counts and harvest rates from hunter-harvest surveys, and are rarely field validated. I developed an alternative method for monitoring population dynamics of wintering populations of mule deer. I designed a hybrid monitoring program that combined annual vital rate monitoring to track changes in population growth rate with a field-based approach for estimating population abundance. The program allocated resources optimally towards the most critical components of mule deer population dynamics, and consisted of 4 field surveys: annual monitoring of age ratios, overwinter fawn survival, and annual doe survival, with field-based estimates of population size only once every 4 years. Surveys were conducted from 2006 to 2008 in Wildlife Management Unit (WMU) 2, Utah, and cost $29,298 per year, prorated over 4 years. Unfortunately, financial constraints prohibit the implementation of this monitoring program in every WMU in Utah. Instead, the program can be implemented in select WMUs throughout the state, with survival data collected in these core units, providing estimates for nearby satellite units. To establish core-satellite unit pairs, I developed a proxy method for determining correlation in survival rates between core and satellite units using model-simulated estimates. I demonstrated this core-satellite method using WMU 2 as a core and WMU 3, an adjacent unit, as a satellite. Finally, I compared a multiple data sources (MDS) model with a herd composition-based population model, POP-II. The MDS model better approximated observed data, and provided statistical rigor. Overall, the hybrid program was less costly and provided more precise estimates of population trend than could be achieved with a monitoring program focused on abundance alone, and was more defensible than herd composition monitoring. After establishing correlations in doe and fawn survival between core and satellite units, data collected in core units via the hybrid program could then be used to model the mule deer population dynamics of other units using MDS modeling procedures. This combined approach could be an effective statewide program for monitoring mule deer populations.
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Tooth lesions and fluoride content in teeth, bones and antlers of mule deer (Odocoileus hemionus)Borrero D., Luz Mercedes 23 June 2009 (has links)
Mule deer (Odocoileus hemionus) from the US Air Force Academy (USAF A) at Colorado Springs, Colorado have shown antler fractures and tooth lesions. Brittle bones and tooth lesions have been associated with high ingestion of fluorides. The present study compared prevalence and severity of tooth lesions with fluoride content in teeth, bones and antlers of mule deer from USAF A with deer from other two areas in Colorado. Mule deer tissues were collected during 1993-1995 from: USAF A (N=262), Pinon Canyon Maneuver Site (pCMS, N=24), and game management units (GMU's) in northwestern Colorado (N=16). The severity of tooth lesions was rated using a 0 (normal) to 5 (severe hypoplasia) scale. In all areas the median lesion score was 1; the highest score in USAFA was 5 vs. 3 in the other areas. Median fluodide concentrations (Jlg/g d.w.) were higher (p<0.002) in second incisors and bones of mule deer collected at the USAFA (669.9, N=246 incisors, 744.5, N=247 bones) than in deer from PCMS (507.3; 494.7, N=24) and GMU's (426.2,466.2, N=16), respectively.
Within the USAF A, median fluoride concentrations in teeth and bones were lower (P<O. 001) in fawns and yearlings than in older animals and in males (> I. 5 years) than in females. Median fluoride concentrations were lower (P<O. 001) in deciduous than in permanent teeth. Median concentrations of fluoride were higher (P<O.OO1) in non-erupted teeth than in deciduous teeth and bone indicating a high rate of accumulating fluoride in growing hard tissue. Fluoride concentration was higher (P<O. 00 1) in teeth with lesions than without lesions. / Master of Science
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Migration, dispersal, and survival patterns of mule deer (<i>Odocoileus hemionus</i>) in a chronic wasting disease-endemic area of southern SaskatchewanSkelton, Nicole Kimberly 21 September 2010
Chronic wasting disease (CWD) has infected wild deer of Saskatchewan for at least the past 10 years. Disease management plans have evolved over the years, but without information on mule deer (<i>Odocoileus hemionus</i>) habits and movements in the grasslands of southern Saskatchewan. We radio-collared and monitored the survival and movements of 206 mule deer from 2006 to 2009. Long distance movements by deer have potential to transfer disease to previously naïve areas. Survival rates had not yet been evaluated in this area; baseline data will provide a useful measure for population-level impacts of the disease in the future.<p>
Juvenile dispersals and adult migrations were contrasted from 4 study areas along the South Saskatchewan River. Dispersal distance (median = 22.8 km, n = 14) was similar to migration distance (median = 16.0 km, n = 49). Median migration distance was similar between males (15.7 km, n = 51) and females (19.7 km, n = 65). Obligatory migrants were more likely to be female. Deer from an area of extensive grassland were more likely to be migratory than their counterparts in fragmented grassland of an agricultural landscape. Maximum migration and dispersal distances were 113 km and 195 km, respectively. Movement paths of 33 GPS-collared deer were best explained by high terrain ruggedness values and proximity to grassland.<p>
Seasonal survival rates showed that deer had lowest survival in autumn months during hunting season. Juveniles had lower survival than adults in all seasons. Harvest regime changes in 2008 improved the autumn survival of adult females but adult males had lower survival than in 2007. Body condition of captured deer was evaluated from residuals of mass-length regression. Cox regression analyses suggested that deer in good body condition (75th percentile) were half as likely to die and that those in very poor body condition (10th percentile) were twice as likely to die. Radio collars that weighed > 2% of body mass negatively affected survival and we recommend future researchers take this into consideration. <p>
Survival, dispersal, and migration rates and patterns are crucial parameters in modeling CWD in local mule deer populations. Saskatchewan wildlife managers aim to prevent CWD spread into new areas, and can use mule deer movement orientations to target surveillance accordingly. White-tailed deer (<i>Odocoileus virginianus</i>) movements are briefly discussed; further knowledge of their movements is required for CWD management in all of Saskatchewan.
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Migration, dispersal, and survival patterns of mule deer (<i>Odocoileus hemionus</i>) in a chronic wasting disease-endemic area of southern SaskatchewanSkelton, Nicole Kimberly 21 September 2010 (has links)
Chronic wasting disease (CWD) has infected wild deer of Saskatchewan for at least the past 10 years. Disease management plans have evolved over the years, but without information on mule deer (<i>Odocoileus hemionus</i>) habits and movements in the grasslands of southern Saskatchewan. We radio-collared and monitored the survival and movements of 206 mule deer from 2006 to 2009. Long distance movements by deer have potential to transfer disease to previously naïve areas. Survival rates had not yet been evaluated in this area; baseline data will provide a useful measure for population-level impacts of the disease in the future.<p>
Juvenile dispersals and adult migrations were contrasted from 4 study areas along the South Saskatchewan River. Dispersal distance (median = 22.8 km, n = 14) was similar to migration distance (median = 16.0 km, n = 49). Median migration distance was similar between males (15.7 km, n = 51) and females (19.7 km, n = 65). Obligatory migrants were more likely to be female. Deer from an area of extensive grassland were more likely to be migratory than their counterparts in fragmented grassland of an agricultural landscape. Maximum migration and dispersal distances were 113 km and 195 km, respectively. Movement paths of 33 GPS-collared deer were best explained by high terrain ruggedness values and proximity to grassland.<p>
Seasonal survival rates showed that deer had lowest survival in autumn months during hunting season. Juveniles had lower survival than adults in all seasons. Harvest regime changes in 2008 improved the autumn survival of adult females but adult males had lower survival than in 2007. Body condition of captured deer was evaluated from residuals of mass-length regression. Cox regression analyses suggested that deer in good body condition (75th percentile) were half as likely to die and that those in very poor body condition (10th percentile) were twice as likely to die. Radio collars that weighed > 2% of body mass negatively affected survival and we recommend future researchers take this into consideration. <p>
Survival, dispersal, and migration rates and patterns are crucial parameters in modeling CWD in local mule deer populations. Saskatchewan wildlife managers aim to prevent CWD spread into new areas, and can use mule deer movement orientations to target surveillance accordingly. White-tailed deer (<i>Odocoileus virginianus</i>) movements are briefly discussed; further knowledge of their movements is required for CWD management in all of Saskatchewan.
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Survival of Neonate Mule Deer Fawns in Southern Utah: Effects of Coyote Removal and Synchrony of ParturitionHall, Jacob Tyler 01 April 2018 (has links)
Mule deer (Odocoileus hemionus) are an iconic species of wildlife, and populations of mule deer across much of the western U.S. have experienced recent fluctuations in size. Factors that affect the survival and subsequent recruitment of juveniles may be the preeminent cause of population fluctuations for mule deer in many areas. Many factors, including habitat loss, extreme weather, intense predation, timing and synchrony of parturition, and competition with other species may be influencing these changes. We studied two potential factors that can influence the survival of neonate mule deer in southern Utah. To better understand how predation affects mule deer, we first implemented a study of the response of mule deer to removal of coyotes in southern Utah. We monitored survival and cause-specific mortality of neonate mule deer in areas where coyotes were removed and where they were not removed. We used multi-model inference within Program MARK and a known-fate model to estimate survival of neonate mule deer in both treatments (removal and non-removal), and to investigate factors potentially influencing survival. Our results indicated that coyote control can decrease mortality and increase survival of neonate mule deer in some situations. Removal of coyotes was most effective when removal efforts occurred for multiple consecutive years, and when control efforts occurred in or near fawning habitat. Second, we examined how synchrony of parturition affects the survival and cause-specific mortality of neonate mule deer. Reproductive synchrony is a strategy that influences the survival of juveniles and the growth of populations. Our objective was to test three possible explanations for the synchrony of parturition in mule deer; 1) pressure of predation on newborns, 2) a hybrid of predation and environmental effects, and 3) weather and food availability. To determine the effects of the timing of parturition on the survival and predator-related mortality of neonate mule deer, we used multi-model inference within Program MARK and a known-fate model. Our results indicated that the timing of parturition influenced survival and predator-related mortality of neonate mule deer. There was a lag between the onset of parturition of mule deer and predation of mule deer by fawns; individuals born close to the onset of parturition had higher survival and lower predator-related mortality than those whose births were delayed relative to the onset of parturition. Since predators selected for neonate mule deer that were born late, predator learning may partially explain reproductive synchrony in mule deer. Environmental factors may have a greater effect than predation on the survival of early-born individuals.
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