Pub Date : 2019-05-29DOI: 10.2192/URSU-D-18-00011.1
Sean M. Murphy, J. Hast, B. Augustine, D. Weisrock, J. D. Clark, David M. Kocka, C. W. Ryan, Jaime L. Sajecki, J. Cox
Abstract: Habitat loss and overexploitation extirpated American black bears (Ursus americanus) from most of the Central Appalachians, USA, by the early 20th Century. To attempt to restore bears to the southwestern portion of this region, 2 reintroductions that used small founder groups (n = 27 and 55 bears), but different release methods (hard vs. soft), were conducted during the 1990s. We collected hair samples from black bears during 2004–2016 in the reintroduced Big South Fork (BSF) and Kentucky–Virginia populations (KVP), their respective Great Smoky Mountains (GSM) and Shenandoah National Park (SNP) source populations, and a neighboring population in southern West Virginia (SWV) to investigate the early genetic outcomes of bear reintroduction. Despite having undergone genetic bottlenecks, genetic diversity remained similar between reintroduced populations and their sources approximately 15 years after the founder events (ranges: AR = 4.86–5.61; HO = 0.67–0.75; HE = 0.65–0.71). Effective population sizes of the reintroduced KVP and BSF (NE = 31 and 36, respectively) were substantially smaller than their respective SNP and GSM sources (NE = 119 and 156, respectively), supporting founder effects. Genetic structure analysis indicated that the hard-released (i.e., no acclimation period) KVP founder group likely declined considerably, whereas the soft-released BSF founder group remained mostly intact, suggesting superior effectiveness of soft releases. Asymmetrical gene flow via immigration from the SWV has resulted in the KVP recovering from the initial founder group reduction. Sustained isolation, small NE, and small population size of the BSF may warrant continued genetic monitoring to determine if gene flow from neighboring populations is established or NE declines. For future bear reintroductions, we suggest managers consider sourcing founders from populations with high genetic diversity and soft-releasing bears to locales that are, if possible, within the dispersal capability of extant populations to mitigate the potential consequences of founder effects and isolation.
{"title":"Early genetic outcomes of American black bear reintroductions in the Central Appalachians, USA","authors":"Sean M. Murphy, J. Hast, B. Augustine, D. Weisrock, J. D. Clark, David M. Kocka, C. W. Ryan, Jaime L. Sajecki, J. Cox","doi":"10.2192/URSU-D-18-00011.1","DOIUrl":"https://doi.org/10.2192/URSU-D-18-00011.1","url":null,"abstract":"Abstract: Habitat loss and overexploitation extirpated American black bears (Ursus americanus) from most of the Central Appalachians, USA, by the early 20th Century. To attempt to restore bears to the southwestern portion of this region, 2 reintroductions that used small founder groups (n = 27 and 55 bears), but different release methods (hard vs. soft), were conducted during the 1990s. We collected hair samples from black bears during 2004–2016 in the reintroduced Big South Fork (BSF) and Kentucky–Virginia populations (KVP), their respective Great Smoky Mountains (GSM) and Shenandoah National Park (SNP) source populations, and a neighboring population in southern West Virginia (SWV) to investigate the early genetic outcomes of bear reintroduction. Despite having undergone genetic bottlenecks, genetic diversity remained similar between reintroduced populations and their sources approximately 15 years after the founder events (ranges: AR = 4.86–5.61; HO = 0.67–0.75; HE = 0.65–0.71). Effective population sizes of the reintroduced KVP and BSF (NE = 31 and 36, respectively) were substantially smaller than their respective SNP and GSM sources (NE = 119 and 156, respectively), supporting founder effects. Genetic structure analysis indicated that the hard-released (i.e., no acclimation period) KVP founder group likely declined considerably, whereas the soft-released BSF founder group remained mostly intact, suggesting superior effectiveness of soft releases. Asymmetrical gene flow via immigration from the SWV has resulted in the KVP recovering from the initial founder group reduction. Sustained isolation, small NE, and small population size of the BSF may warrant continued genetic monitoring to determine if gene flow from neighboring populations is established or NE declines. For future bear reintroductions, we suggest managers consider sourcing founders from populations with high genetic diversity and soft-releasing bears to locales that are, if possible, within the dispersal capability of extant populations to mitigate the potential consequences of founder effects and isolation.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85068867","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-29DOI: 10.2192/URSUS-D-18-00008.1
G. Hilderbrand, D. Gustine, K. Joly, B. Mangipane, W. Leacock, Matthew D. Cameron, M. Sorum, Lindsey S. Mangipane, Joy A. Erlenbach
Abstract: Recruitment of brown bear (Ursus arctos) offspring into a population is the product of initial cub production and subsequent survival and is a critical component of overall population status and trend. We investigated the relationship between maternal body size, body condition, and age (as a surrogate for gained experience) and recruitment of dependent offspring (≥1 yr old) in 4 Alaska, USA (2014–2017), brown bear populations using logistic regression. Body size alone was our top predictor of the presence of offspring and appeared in all top models. Our data suggest that bear size is the primary driver of productivity across all 4 study populations, with larger bears having a greater chance of being observed with offspring. The effect of body condition was likely confounded by the increased energetic costs of supporting cubs through time and had a negative relationship with recruitment. Age (experience) was positively related to recruitment. Understanding the relative importance of body size, body condition, and age on the recruitment of offspring provides insights into life-history trade-offs female bears must manage as they strive to meet the nutritional costs of cub production and rearing, while minimizing risks to themselves and their offspring. Further assessment of long-term longitudinal studies of brown bears that assess the lifetime reproductive output of individuals would be highly informative to further assess the effect of experience on recruitment and to support the management of brown bear populations for recovery, conservation, sustained yield, and ecosystem function.
{"title":"Influence of maternal body size, condition, and age on recruitment of four brown bear populations","authors":"G. Hilderbrand, D. Gustine, K. Joly, B. Mangipane, W. Leacock, Matthew D. Cameron, M. Sorum, Lindsey S. Mangipane, Joy A. Erlenbach","doi":"10.2192/URSUS-D-18-00008.1","DOIUrl":"https://doi.org/10.2192/URSUS-D-18-00008.1","url":null,"abstract":"Abstract: Recruitment of brown bear (Ursus arctos) offspring into a population is the product of initial cub production and subsequent survival and is a critical component of overall population status and trend. We investigated the relationship between maternal body size, body condition, and age (as a surrogate for gained experience) and recruitment of dependent offspring (≥1 yr old) in 4 Alaska, USA (2014–2017), brown bear populations using logistic regression. Body size alone was our top predictor of the presence of offspring and appeared in all top models. Our data suggest that bear size is the primary driver of productivity across all 4 study populations, with larger bears having a greater chance of being observed with offspring. The effect of body condition was likely confounded by the increased energetic costs of supporting cubs through time and had a negative relationship with recruitment. Age (experience) was positively related to recruitment. Understanding the relative importance of body size, body condition, and age on the recruitment of offspring provides insights into life-history trade-offs female bears must manage as they strive to meet the nutritional costs of cub production and rearing, while minimizing risks to themselves and their offspring. Further assessment of long-term longitudinal studies of brown bears that assess the lifetime reproductive output of individuals would be highly informative to further assess the effect of experience on recruitment and to support the management of brown bear populations for recovery, conservation, sustained yield, and ecosystem function.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82581078","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-29DOI: 10.2192/URSUS-D-18-00015.1
K. Archibald, Kristina Baltutis, M. Stoskopf, C. Bailey
Abstract: Prolonged reproductive behavior of American black bears (Ursus americanus) has been reported in the southeastern United States compared with other regions, but functional spermatogenesis or potential fertility has not previously been described for these bears. Additionally, methods for gamete collection are only in early stages of development for ursids. Testicles were collected from 29 post-pubertal legally hunter-killed black bears in eastern North Carolina, USA, in November 2016. Active spermatogenesis was identified in 48.3% (14/29) of bears via histology. Epididymal sperm collection was attempted via mincing (n = 29), vas deferens flush (n = 24), and percutaneous aspiration (n = 5). Epididymal mincing identified sperm in 78.6%, and vas flush in 53.8%, of bears with spermatogenesis on histology. Percutaneous aspiration was unsuccessful. These findings provide evidence that male bears may maintain reproductive capabilities into the late autumn in this region, and that under the conditions of this study, sperm can be collected via epididymal mincing or vas deferens flush, but not percutaneous aspiration.
{"title":"Testicular activity and epididymal sperm collection from American black bears in November","authors":"K. Archibald, Kristina Baltutis, M. Stoskopf, C. Bailey","doi":"10.2192/URSUS-D-18-00015.1","DOIUrl":"https://doi.org/10.2192/URSUS-D-18-00015.1","url":null,"abstract":"Abstract: Prolonged reproductive behavior of American black bears (Ursus americanus) has been reported in the southeastern United States compared with other regions, but functional spermatogenesis or potential fertility has not previously been described for these bears. Additionally, methods for gamete collection are only in early stages of development for ursids. Testicles were collected from 29 post-pubertal legally hunter-killed black bears in eastern North Carolina, USA, in November 2016. Active spermatogenesis was identified in 48.3% (14/29) of bears via histology. Epididymal sperm collection was attempted via mincing (n = 29), vas deferens flush (n = 24), and percutaneous aspiration (n = 5). Epididymal mincing identified sperm in 78.6%, and vas flush in 53.8%, of bears with spermatogenesis on histology. Percutaneous aspiration was unsuccessful. These findings provide evidence that male bears may maintain reproductive capabilities into the late autumn in this region, and that under the conditions of this study, sperm can be collected via epididymal mincing or vas deferens flush, but not percutaneous aspiration.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82255198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Ruiz-Villar, A. Morales-González, G. Bombieri, A. Zarzo‐Arias, V. Penteriani
Abstract: We characterized a brown bear (Ursus arctos) feeding aggregation that occurred in an oak (Quercus spp.) forest in the Cantabrian Mountains (NW Spain), during the hyperphagia period 2017 (Sep to Dec), which was an atypical year in terms of low fructification success due to late frost events and drought. We described (1) number, sex, and age class of aggregated bears; (2) temporal use of the area; and (3) bear interactions. We identified a minimum of 31 individuals, representing 10% of the estimated Cantabrian bear population. The number of adults increased during the study period, whereas the number of subadults decreased, which could be related to a displacement of subadults by dominant adults. The proximity of the aggregation site to a public road attracted numerous people to observe the bears. To minimize adverse bear–human interactions, we recommend providing educational material on best bear-viewing practices as well as on-site staffing.
{"title":"Characterization of a brown bear aggregation during the hyperphagia period in the Cantabrian Mountains, NW Spain","authors":"H. Ruiz-Villar, A. Morales-González, G. Bombieri, A. Zarzo‐Arias, V. Penteriani","doi":"10.2192/URSU-D-29-1.1","DOIUrl":"https://doi.org/10.2192/URSU-D-29-1.1","url":null,"abstract":"Abstract: We characterized a brown bear (Ursus arctos) feeding aggregation that occurred in an oak (Quercus spp.) forest in the Cantabrian Mountains (NW Spain), during the hyperphagia period 2017 (Sep to Dec), which was an atypical year in terms of low fructification success due to late frost events and drought. We described (1) number, sex, and age class of aggregated bears; (2) temporal use of the area; and (3) bear interactions. We identified a minimum of 31 individuals, representing 10% of the estimated Cantabrian bear population. The number of adults increased during the study period, whereas the number of subadults decreased, which could be related to a displacement of subadults by dominant adults. The proximity of the aggregation site to a public road attracted numerous people to observe the bears. To minimize adverse bear–human interactions, we recommend providing educational material on best bear-viewing practices as well as on-site staffing.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-05-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74125732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-24DOI: 10.2192/URSUS-D-18-00012.1
F. Bled, J. Belant
Abstract: Management of large carnivore populations represents an important challenge in conservation, requiring balancing their cultural, economic, and ecological value with potential risks of human–wildlife conflicts. Harvest can provide an effective tool for managing populations, but it can be difficult to define appropriate harvest quotas or assess the consequences of other conservation measures. We introduce the web-application ‘demetR’ (“Dynamic Environment for Modeling and Estimating Trajectories in R,” available at https://pop-eco.shinyapps.io/demetR/) to evaluate the effects of harvest scenarios and other conservation policies on brown bear (Ursus arctos) and American black bear (U. americanus) populations. We developed a Bayesian population trajectory model to simulate brown bear and black bear populations in response to user-defined demographic parameters and harvest. Model simulations are performed using fixed or stochastic demographic parameters, allowing for informative and non-informative priors. We provide an overview of the general layout, along with descriptions of model inputs and outputs. We then provide examples of bear populations simulated using deterministic and stochastic approaches with varying levels of harvest. Performing computer simulations of different management scenarios offers an economical and efficient way to test practices before their application, and can be valuable for decision-making. This model can also be applied to other species with similar life-history traits. Future developments will provide users with greater input flexibility and adaptations to specific population structures of other large carnivores. Management decisions can be costly, with long-lasting ecological and economic consequences. Models such as the one we present here, in the context of structured decision-making and adaptive management, can improve the quality and quantity of information needed to make these decisions.
{"title":"demetR: a Bayesian population simulation web-application for harvest management","authors":"F. Bled, J. Belant","doi":"10.2192/URSUS-D-18-00012.1","DOIUrl":"https://doi.org/10.2192/URSUS-D-18-00012.1","url":null,"abstract":"Abstract: Management of large carnivore populations represents an important challenge in conservation, requiring balancing their cultural, economic, and ecological value with potential risks of human–wildlife conflicts. Harvest can provide an effective tool for managing populations, but it can be difficult to define appropriate harvest quotas or assess the consequences of other conservation measures. We introduce the web-application ‘demetR’ (“Dynamic Environment for Modeling and Estimating Trajectories in R,” available at https://pop-eco.shinyapps.io/demetR/) to evaluate the effects of harvest scenarios and other conservation policies on brown bear (Ursus arctos) and American black bear (U. americanus) populations. We developed a Bayesian population trajectory model to simulate brown bear and black bear populations in response to user-defined demographic parameters and harvest. Model simulations are performed using fixed or stochastic demographic parameters, allowing for informative and non-informative priors. We provide an overview of the general layout, along with descriptions of model inputs and outputs. We then provide examples of bear populations simulated using deterministic and stochastic approaches with varying levels of harvest. Performing computer simulations of different management scenarios offers an economical and efficient way to test practices before their application, and can be valuable for decision-making. This model can also be applied to other species with similar life-history traits. Future developments will provide users with greater input flexibility and adaptations to specific population structures of other large carnivores. Management decisions can be costly, with long-lasting ecological and economic consequences. Models such as the one we present here, in the context of structured decision-making and adaptive management, can improve the quality and quantity of information needed to make these decisions.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78605605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2019-05-16DOI: 10.2192/URSUS-D-18-00009.1
Abbey E. Wilson, D. Sparks, Katrina K. Knott, S. Willard, Ashli Brown, T. Connor, Zejun Zhang
Abstract: Giant pandas (Ailuropoda melanoleuca) use chemical cues to determine identity, gender, and sexual receptivity of conspecifics. We hypothesized that volatile chemical profiles of free-ranging giant pandas are detectable in air. Therefore, we aimed to identify volatile compounds produced by free-ranging giant pandas residing in the Wolong Nature Reserve (Sichuan, China) through field air analysis/solid phase microextraction/gas chromatography–mass spectrometry (FAA/SPME/GCMS). From 28 June to 12 July 2017, 3 SPME fibers were secured to trees that appeared to have previous marking activity. Trail cameras confirmed that a single giant panda performed scent-marking behavior at one sampling location. The abundance of 7 compounds were elevated in samples collected from the tree visited by the giant panda compared with controls. Three of these compounds (Ethane, 1,1-dinitro-; Octane, 4-ethyl-; 2(1H)-Pyridinethione, 3-ethoxy-6-methyl-) were unique to the giant panda visit. Novel methods to detect giant pandas would benefit conservation efforts. We suggest our method also may be used to study chemical communication in other bear species.
{"title":"Field air analysis of volatile compounds from free-ranging giant pandas","authors":"Abbey E. Wilson, D. Sparks, Katrina K. Knott, S. Willard, Ashli Brown, T. Connor, Zejun Zhang","doi":"10.2192/URSUS-D-18-00009.1","DOIUrl":"https://doi.org/10.2192/URSUS-D-18-00009.1","url":null,"abstract":"Abstract: Giant pandas (Ailuropoda melanoleuca) use chemical cues to determine identity, gender, and sexual receptivity of conspecifics. We hypothesized that volatile chemical profiles of free-ranging giant pandas are detectable in air. Therefore, we aimed to identify volatile compounds produced by free-ranging giant pandas residing in the Wolong Nature Reserve (Sichuan, China) through field air analysis/solid phase microextraction/gas chromatography–mass spectrometry (FAA/SPME/GCMS). From 28 June to 12 July 2017, 3 SPME fibers were secured to trees that appeared to have previous marking activity. Trail cameras confirmed that a single giant panda performed scent-marking behavior at one sampling location. The abundance of 7 compounds were elevated in samples collected from the tree visited by the giant panda compared with controls. Three of these compounds (Ethane, 1,1-dinitro-; Octane, 4-ethyl-; 2(1H)-Pyridinethione, 3-ethoxy-6-methyl-) were unique to the giant panda visit. Novel methods to detect giant pandas would benefit conservation efforts. We suggest our method also may be used to study chemical communication in other bear species.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2019-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91086243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.2192/URSUS-D-17-00004.2
Toryn L. J. Schafer, S. Breck, S. Baruch‐Mordo, D. Lewis, K. R. Wilson, J. Mao, Thomas L. Day
Abstract Selection of den sites is a crucial aspect of American black bear (Ursus americanus) life history. High-quality dens provide thermal insulation, protection from disturbance, suitable environment for parturition and cub development, and proximity to available forage upon emergence. Black bears are increasingly coexisting with people in human-dominated landscapes; however, little is known about whether urban environments influence characteristics of dens and den site selection. Our objective was to determine the effect of housing density (a proxy for human activity and availability of anthropogenic resources) on selection of den sites in years of good and poor natural forage. We additionally compared size, shape, and location of dens of males and females to describe den characteristics and explore whether differences existed between males and females. We revisited 34 den locations detected during a 6-year (2005–2010) urban black bear study in Aspen, Colorado, USA, and measured den entrance and den volume. We fit a conditional logistic regression model using a resource selection function framework to determine the importance of housing density and other landscape variables (elevation, slope, aspect, and vegetation type) associated with den site selection. Slope was the best predictor of den site selection and there was no relationship between den selection and housing density, indicating that black bears were neither avoiding nor seeking urban areas for denning. Dens were smaller for females ( = 3.30 m3, SE = 1.94, n = 22) than for males ( = 7.56 m3, SE = 3.31, n = 8), supporting the idea that females have greater constraints in den characteristics, possibly related to cub development and security from predation or because females generally are smaller than males.
穴址的选择是美洲黑熊生活史的一个重要方面。高质量的洞穴提供隔热，保护免受干扰，适合分娩和幼崽发育的环境，并且在出现时接近可用的饲料。黑熊越来越多地在人类主导的景观中与人类共存;然而，关于城市环境是否影响洞穴特征和洞穴选址，人们知之甚少。我们的目标是确定房屋密度(人类活动和人为资源可用性的代表)在自然饲料质量好和质量差的年份对洞穴地点选择的影响。此外，我们还比较了雄性和雌性洞穴的大小、形状和位置，以描述洞穴特征，并探讨雄性和雌性之间是否存在差异。我们重新考察了美国科罗拉多州阿斯彭市6年(2005-2010年)城市黑熊研究中发现的34个洞穴位置，并测量了洞穴入口和洞穴体积。我们使用资源选择函数框架拟合条件逻辑回归模型，以确定住房密度和其他与洞穴选址相关的景观变量(海拔、坡度、坡向和植被类型)的重要性。坡度是熊穴选择的最佳预测因子，而熊穴选择与生境密度之间没有关系，说明熊穴既不躲避也不寻找城市区域。雌鼠的洞穴(= 3.30 m3, SE = 1.94, n = 22)小于雄鼠(= 7.56 m3, SE = 3.31, n = 8)，这支持了雌性在洞穴特征方面受到更大约束的观点，可能与幼崽发育和捕食安全有关，或者因为雌性通常比雄性小。
{"title":"American black bear den-site selection and characteristics in an urban environment","authors":"Toryn L. J. Schafer, S. Breck, S. Baruch‐Mordo, D. Lewis, K. R. Wilson, J. Mao, Thomas L. Day","doi":"10.2192/URSUS-D-17-00004.2","DOIUrl":"https://doi.org/10.2192/URSUS-D-17-00004.2","url":null,"abstract":"Abstract Selection of den sites is a crucial aspect of American black bear (Ursus americanus) life history. High-quality dens provide thermal insulation, protection from disturbance, suitable environment for parturition and cub development, and proximity to available forage upon emergence. Black bears are increasingly coexisting with people in human-dominated landscapes; however, little is known about whether urban environments influence characteristics of dens and den site selection. Our objective was to determine the effect of housing density (a proxy for human activity and availability of anthropogenic resources) on selection of den sites in years of good and poor natural forage. We additionally compared size, shape, and location of dens of males and females to describe den characteristics and explore whether differences existed between males and females. We revisited 34 den locations detected during a 6-year (2005–2010) urban black bear study in Aspen, Colorado, USA, and measured den entrance and den volume. We fit a conditional logistic regression model using a resource selection function framework to determine the importance of housing density and other landscape variables (elevation, slope, aspect, and vegetation type) associated with den site selection. Slope was the best predictor of den site selection and there was no relationship between den selection and housing density, indicating that black bears were neither avoiding nor seeking urban areas for denning. Dens were smaller for females ( = 3.30 m3, SE = 1.94, n = 22) than for males ( = 7.56 m3, SE = 3.31, n = 8), supporting the idea that females have greater constraints in den characteristics, possibly related to cub development and security from predation or because females generally are smaller than males.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83055650","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.2192/URSUS-D-16-00017.1
Mehdi Ansari H., A. Ghoddousi
Abstract Large carnivores are among the most threatened species in the world because of their natural low densities and need for expansive habitats. The brown bear (Ursus arctos) is the largest carnivore in the southwestern Asia, and faces threats in much of its range from conflict with humans over shared resources and shrinkage of habitat. In this study, we surveyed for brown bear sign and scat during spring–autumn from April 2013 to November 2015 in 24 randomly selected, 25-km2 grid cells, and developed a model of potential brown bear occurrence in one of its globally southernmost distribution ranges in Iran. To better understand its conservation needs and management priorities at the landscape scale, we used a combination of field surveys to develop a Maximum Entropy (Maxent) model. The model was developed using 10 environmental and anthropogenic predictors. Potential brown bear occurrence was strongly influenced by availability of water resources (54.1%) as the most important variable; and distance to roads (16.1%), aspect (7.6%), and vegetation types (5.9%) were the other important factors. The model showed an area of 581 km2 (35%) within the study area has high to good bear-occurrence probability values; 86% of this area is located in 2 patches, each larger than the average bear home range. Identification of these patches may support establishment of a reserve in the area, which would ensure long-term survival of the brown bear and sustainable water use and resource extraction from Pistacia atlantica forests by resident and nomadic communities in the region.
{"title":"Water availability limits brown bear distribution at the southern edge of its global range","authors":"Mehdi Ansari H., A. Ghoddousi","doi":"10.2192/URSUS-D-16-00017.1","DOIUrl":"https://doi.org/10.2192/URSUS-D-16-00017.1","url":null,"abstract":"Abstract Large carnivores are among the most threatened species in the world because of their natural low densities and need for expansive habitats. The brown bear (Ursus arctos) is the largest carnivore in the southwestern Asia, and faces threats in much of its range from conflict with humans over shared resources and shrinkage of habitat. In this study, we surveyed for brown bear sign and scat during spring–autumn from April 2013 to November 2015 in 24 randomly selected, 25-km2 grid cells, and developed a model of potential brown bear occurrence in one of its globally southernmost distribution ranges in Iran. To better understand its conservation needs and management priorities at the landscape scale, we used a combination of field surveys to develop a Maximum Entropy (Maxent) model. The model was developed using 10 environmental and anthropogenic predictors. Potential brown bear occurrence was strongly influenced by availability of water resources (54.1%) as the most important variable; and distance to roads (16.1%), aspect (7.6%), and vegetation types (5.9%) were the other important factors. The model showed an area of 581 km2 (35%) within the study area has high to good bear-occurrence probability values; 86% of this area is located in 2 patches, each larger than the average bear home range. Identification of these patches may support establishment of a reserve in the area, which would ensure long-term survival of the brown bear and sustainable water use and resource extraction from Pistacia atlantica forests by resident and nomadic communities in the region.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89758663","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.2192/URSUS-D-17-00024.2
P. Thatte, Kaushalkumar Patel, U. Ramakrishnan
Abstract Once common throughout the Indian subcontinent, the sloth bear (Melursus ursinus) is restricted to certain areas and is classified as vulnerable by the International Union for Conservation of Nature. Habitat loss and fragmentation is the primary reason for population decline, but there is a dearth of information about the effects of fragmentation on connectivity and genetic variation. Non-invasive DNA samples are commonly used to investigate connectivity and monitor populations in the wild. We developed a polymerase chain reaction (PCR) –based technique to identify sloth bears from non-invasively collected samples. Three sets of primers were designed to amplify short fragments of mitochondrial DNA to reduce false negatives, which is an issue with non-invasively collected DNA. The PCR success rate in both fresh and dry samples was high (88%). Failure to amplify DNA from other co-occurring mammals confirmed species specificity. This approach provides an efficient method to identify sloth bear samples using non-invasively collected DNA.
{"title":"Rapid species identification of sloth bears from non-invasive samples: a PCR-based assay","authors":"P. Thatte, Kaushalkumar Patel, U. Ramakrishnan","doi":"10.2192/URSUS-D-17-00024.2","DOIUrl":"https://doi.org/10.2192/URSUS-D-17-00024.2","url":null,"abstract":"Abstract Once common throughout the Indian subcontinent, the sloth bear (Melursus ursinus) is restricted to certain areas and is classified as vulnerable by the International Union for Conservation of Nature. Habitat loss and fragmentation is the primary reason for population decline, but there is a dearth of information about the effects of fragmentation on connectivity and genetic variation. Non-invasive DNA samples are commonly used to investigate connectivity and monitor populations in the wild. We developed a polymerase chain reaction (PCR) –based technique to identify sloth bears from non-invasively collected samples. Three sets of primers were designed to amplify short fragments of mitochondrial DNA to reduce false negatives, which is an issue with non-invasively collected DNA. The PCR success rate in both fresh and dry samples was high (88%). Failure to amplify DNA from other co-occurring mammals confirmed species specificity. This approach provides an efficient method to identify sloth bear samples using non-invasively collected DNA.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90645224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-12-01DOI: 10.2192/URSU-D-17-00016.2
Hungling Liu, R. Sharp
Abstract Applying an integrative approach incorporating attitudes toward wildlife in general and toward a specific species (American black bear [Ursus americanus]) can help land managers make decisions about the complex issue of human–bear interactions. The purpose of our study was to (1) assess park visitors’ attitudes toward wildlife, black bears, and possible management actions related to black bears in a park setting; (2) identify the impact of general attitudes toward wildlife and specific attitudes toward black bear on park visitors’ support for various black bear management actions; and (3) to examine whether visitor demographics affect their support for management actions. From March through September 2013, 364 visitors to the Big South Fork National River and Recreation Area (a unit of the U.S. National Park Service located in the southeastern United States) completed a survey, resulting in a 72% response rate. Park visitors generally expressed a positive attitude toward wildlife education and enjoyment of seeing wildlife, while they were more polarized on the importance of wildlife management and their appreciation of wildlife through hunting. Hierarchical regression analyses indicated that park visitors’ attitudes were better predictors of support for management than were their demographic characteristics. Park visitors who agreed that “people appreciate wildlife through hunting” and “bears are a threat to people” were likely to accept lethal management actions. Their attitudes toward hunting in general were the most significant predictors of acceptance of lethal management actions. Park visitors’ positive attitudes toward black bear conservation and acceptance of the current number of black bears in the park were predictors of their acceptance of non-lethal management actions. The number of human–bear interactions in the park currently is small; and this proactive study expands possible management options with the intent of preventing and minimizing human–bear conflicts in a protected area where people recreate and wildlife coexists.
{"title":"Influence of attitudes toward wildlife on preferences for management of American black bears","authors":"Hungling Liu, R. Sharp","doi":"10.2192/URSU-D-17-00016.2","DOIUrl":"https://doi.org/10.2192/URSU-D-17-00016.2","url":null,"abstract":"Abstract Applying an integrative approach incorporating attitudes toward wildlife in general and toward a specific species (American black bear [Ursus americanus]) can help land managers make decisions about the complex issue of human–bear interactions. The purpose of our study was to (1) assess park visitors’ attitudes toward wildlife, black bears, and possible management actions related to black bears in a park setting; (2) identify the impact of general attitudes toward wildlife and specific attitudes toward black bear on park visitors’ support for various black bear management actions; and (3) to examine whether visitor demographics affect their support for management actions. From March through September 2013, 364 visitors to the Big South Fork National River and Recreation Area (a unit of the U.S. National Park Service located in the southeastern United States) completed a survey, resulting in a 72% response rate. Park visitors generally expressed a positive attitude toward wildlife education and enjoyment of seeing wildlife, while they were more polarized on the importance of wildlife management and their appreciation of wildlife through hunting. Hierarchical regression analyses indicated that park visitors’ attitudes were better predictors of support for management than were their demographic characteristics. Park visitors who agreed that “people appreciate wildlife through hunting” and “bears are a threat to people” were likely to accept lethal management actions. Their attitudes toward hunting in general were the most significant predictors of acceptance of lethal management actions. Park visitors’ positive attitudes toward black bear conservation and acceptance of the current number of black bears in the park were predictors of their acceptance of non-lethal management actions. The number of human–bear interactions in the park currently is small; and this proactive study expands possible management options with the intent of preventing and minimizing human–bear conflicts in a protected area where people recreate and wildlife coexists.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":null,"pages":null},"PeriodicalIF":1.3,"publicationDate":"2018-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75199277","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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