Pub Date : 2021-08-20DOI: 10.2192/URSUS-D-19-00031.3
U. Goursi, M. Anwar, L. Bosso, M. Nawaz, M. Kabir
Abstract: The Asiatic black bear (Ursus thibetanus) is globally listed as “Vulnerable.” Here, we documented its current distribution and the human–bear conflict in Machiara National Park (MNP, northern Pakistan) from 2009 to 2013. Our observations indicated that this bear occurs in all areas of MNP, especially at elevations between 1,600 and 3,300 m above sea level. We recorded the greatest activity in May and September. Our questionnaire survey indicated that the majority of survey participants were not in favor of coexistence with this bear. The Asiatic black bear urgently needs effective management plans to guarantee its conservation in Pakistan.
{"title":"Spatial distribution of the threatened Asiatic black bear in northern Pakistan","authors":"U. Goursi, M. Anwar, L. Bosso, M. Nawaz, M. Kabir","doi":"10.2192/URSUS-D-19-00031.3","DOIUrl":"https://doi.org/10.2192/URSUS-D-19-00031.3","url":null,"abstract":"Abstract: The Asiatic black bear (Ursus thibetanus) is globally listed as “Vulnerable.” Here, we documented its current distribution and the human–bear conflict in Machiara National Park (MNP, northern Pakistan) from 2009 to 2013. Our observations indicated that this bear occurs in all areas of MNP, especially at elevations between 1,600 and 3,300 m above sea level. We recorded the greatest activity in May and September. Our questionnaire survey indicated that the majority of survey participants were not in favor of coexistence with this bear. The Asiatic black bear urgently needs effective management plans to guarantee its conservation in Pakistan.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"2 1","pages":"1 - 5"},"PeriodicalIF":1.3,"publicationDate":"2021-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81290634","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 : 2021-08-20DOI: 10.2192/URSUS-D-20-00005.3
Wilhelm H. A. Osterman, F. Cornejo, J. Osterman
Abstract: Peru is probably home to the largest population of Andean bears (Tremarctos ornatus; Peyton 1999); however, no studies have assessed the density and ecology of the species in this region in the past 20 years. Population density estimates are a cornerstone of species conservation because they help guide decision-making and monitoring of species trends. Here, we study Andean bear population density in a small area (i.e., visible area: 352 ha), Copal, in the Amazonas region in Peru between 2015 and 2017. To estimate Andean bear density, we used 3 methods: one based on capture–recapture data of bears, one based on an occupancy model, and one based on the frequency of a uniquely colored bear compared with the frequency of other black Andean bears. Our results estimated Andean bear densities between 8.85 and 17.39 bears/100 km2; we considered our estimate of 10.38 bears/100 km2 from capture–recapture data to be the most reliable. We also recalculated Andean bear density results from Ecuador by Molina et al. (2017), which provided a similar estimate of 11.49 bears/100 km2. Additionally, we report a unique finding of a bear with a golden brown pelage, which we suspect to be the first case in Andean bears. During behavioral observations, Andean bears were predominantly feeding. We suggest that, although Andean bears have large home ranges, a few small areas may be of disproportionate importance to a population. Protecting small areas frequently used by a large number of bears could be an effective mean for Andean bear conservation where large reserves are not a feasible option. We also recognize the need for large-scale studies using a spatial capture–recapture framework, and to associate the results of Andean bear density with resource use in order to successfully protect high-value Andean bear habitat.
{"title":"An Andean bear population hotspot in Northern Peru","authors":"Wilhelm H. A. Osterman, F. Cornejo, J. Osterman","doi":"10.2192/URSUS-D-20-00005.3","DOIUrl":"https://doi.org/10.2192/URSUS-D-20-00005.3","url":null,"abstract":"Abstract: Peru is probably home to the largest population of Andean bears (Tremarctos ornatus; Peyton 1999); however, no studies have assessed the density and ecology of the species in this region in the past 20 years. Population density estimates are a cornerstone of species conservation because they help guide decision-making and monitoring of species trends. Here, we study Andean bear population density in a small area (i.e., visible area: 352 ha), Copal, in the Amazonas region in Peru between 2015 and 2017. To estimate Andean bear density, we used 3 methods: one based on capture–recapture data of bears, one based on an occupancy model, and one based on the frequency of a uniquely colored bear compared with the frequency of other black Andean bears. Our results estimated Andean bear densities between 8.85 and 17.39 bears/100 km2; we considered our estimate of 10.38 bears/100 km2 from capture–recapture data to be the most reliable. We also recalculated Andean bear density results from Ecuador by Molina et al. (2017), which provided a similar estimate of 11.49 bears/100 km2. Additionally, we report a unique finding of a bear with a golden brown pelage, which we suspect to be the first case in Andean bears. During behavioral observations, Andean bears were predominantly feeding. We suggest that, although Andean bears have large home ranges, a few small areas may be of disproportionate importance to a population. Protecting small areas frequently used by a large number of bears could be an effective mean for Andean bear conservation where large reserves are not a feasible option. We also recognize the need for large-scale studies using a spatial capture–recapture framework, and to associate the results of Andean bear density with resource use in order to successfully protect high-value Andean bear habitat.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"24 1","pages":"1 - 10"},"PeriodicalIF":1.3,"publicationDate":"2021-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89672866","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 : 2021-08-03DOI: 10.2192/URSUS-D-19-00024.2
Tomoki Mori, R. Sugiura, Makoto Kato, Kensuke Miura, Haruna Ogawa, Shota Umano, Haruki Kato, S. Izumiyama, Y. Niizuma
Abstract: Increased occurrences of bears in human settlements in search of food have led to a high incidence of human–bear interactions in Japan; therefore, a better understanding of bear occurrence in relation to bears' diet is required to establish effective management practices. In this study, we investigated the composition of the diet of Asiatic black bears (Ursus thibetanus) and the number of bear sightings in Shirakawa Village, Gifu Prefecture, Japan, during pre- and hyperphagic periods (Aug–Dec) from 2008 to 2016. In years with low numbers of sightings, bears consumed natural foods in natural areas, such as fruits of Japanese bird cherry (Prunus grayana), dogwood (Swida controversa), oak (Quercus spp.), and beech (Fagus crenata), which constituted the main part of the bears' diet in our study area. In years with a medium number of sightings, bears consumed both natural and anthropogenic foods in or near human habitations, such as Japanese chestnut (Castanea crenata) and kaki (Diospyros kaki). In the high-sighting year of 2014, bears exhibited a particularly strong preference for Japanese walnut (Juglans mandshurica) and kaki. The number of bear sightings was negatively related to the consumption rates of Japanese bird cherry, dogwood, oak, and beech, and positively related to the consumption rates of Japanese walnut, Japanese chestnut, and kaki. These findings suggest that consumption of fleshy fruits in late summer or hard mast in autumn in or near human settlements has a large effect on the risk of bear–human interactions.
{"title":"Relationship between diet and occurrence around human settlements in Asiatic black bears","authors":"Tomoki Mori, R. Sugiura, Makoto Kato, Kensuke Miura, Haruna Ogawa, Shota Umano, Haruki Kato, S. Izumiyama, Y. Niizuma","doi":"10.2192/URSUS-D-19-00024.2","DOIUrl":"https://doi.org/10.2192/URSUS-D-19-00024.2","url":null,"abstract":"Abstract: Increased occurrences of bears in human settlements in search of food have led to a high incidence of human–bear interactions in Japan; therefore, a better understanding of bear occurrence in relation to bears' diet is required to establish effective management practices. In this study, we investigated the composition of the diet of Asiatic black bears (Ursus thibetanus) and the number of bear sightings in Shirakawa Village, Gifu Prefecture, Japan, during pre- and hyperphagic periods (Aug–Dec) from 2008 to 2016. In years with low numbers of sightings, bears consumed natural foods in natural areas, such as fruits of Japanese bird cherry (Prunus grayana), dogwood (Swida controversa), oak (Quercus spp.), and beech (Fagus crenata), which constituted the main part of the bears' diet in our study area. In years with a medium number of sightings, bears consumed both natural and anthropogenic foods in or near human habitations, such as Japanese chestnut (Castanea crenata) and kaki (Diospyros kaki). In the high-sighting year of 2014, bears exhibited a particularly strong preference for Japanese walnut (Juglans mandshurica) and kaki. The number of bear sightings was negatively related to the consumption rates of Japanese bird cherry, dogwood, oak, and beech, and positively related to the consumption rates of Japanese walnut, Japanese chestnut, and kaki. These findings suggest that consumption of fleshy fruits in late summer or hard mast in autumn in or near human settlements has a large effect on the risk of bear–human interactions.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"8 1","pages":"1 - 10"},"PeriodicalIF":1.3,"publicationDate":"2021-08-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75049041","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 : 2021-07-29DOI: 10.2192/URSUS-D-20-00008.1
M. L. Allen, H. Wittmer, Akino Ingaki, K. Yamazaki, S. Koike
Abstract: Food caching is a common behavior for many mammals, but less is known about the prevalence and importance of food caching for some species. Here we report the first documented caching events by Asiatic black bears (Ursus thibetanus, n = 5) in Japan and 3 additional caching events by American black bears (U. americanus) in California, USA. We also performed a systematic literature review on caching by bears as a reference point for future investigations. Caching was most frequently reported for brown bears (U. arctos), and most caching by bears occurred with large prey. Caching is most likely used to protect large carcasses from spoiling or detection by scavengers, allowing bears to consume more of the carcass. The lack of published studies on caching by bears may be due to the behavior being infrequently used and difficult to record. We encourage an increase, but also consistency, in future reporting, including specific descriptions of caching behavior.
摘要:食物贮藏是许多哺乳动物的一种常见行为，但对某些物种食物贮藏的普遍性和重要性知之甚少。本文首次报道了亚洲黑熊(Ursus thibetanus, n = 5)在日本和美国黑熊(U. americanus)在美国加利福尼亚州的贮藏事件。我们还对熊的贮藏行为进行了系统的文献综述，作为未来研究的参考点。据报道，在棕熊(U. arctos)中最常见的是缓存行为，而且大多数熊的缓存行为发生在大型猎物身上。贮藏最有可能用来保护大型尸体不被腐烂或被食腐动物发现，让熊吃掉更多的尸体。关于熊的缓存行为缺乏发表的研究可能是由于这种行为不经常使用且难以记录。我们鼓励在未来的报告中增加，但也要保持一致性，包括对缓存行为的具体描述。
{"title":"Food caching by bears: A literature review and new observations for Asiatic and American black bears","authors":"M. L. Allen, H. Wittmer, Akino Ingaki, K. Yamazaki, S. Koike","doi":"10.2192/URSUS-D-20-00008.1","DOIUrl":"https://doi.org/10.2192/URSUS-D-20-00008.1","url":null,"abstract":"Abstract: Food caching is a common behavior for many mammals, but less is known about the prevalence and importance of food caching for some species. Here we report the first documented caching events by Asiatic black bears (Ursus thibetanus, n = 5) in Japan and 3 additional caching events by American black bears (U. americanus) in California, USA. We also performed a systematic literature review on caching by bears as a reference point for future investigations. Caching was most frequently reported for brown bears (U. arctos), and most caching by bears occurred with large prey. Caching is most likely used to protect large carcasses from spoiling or detection by scavengers, allowing bears to consume more of the carcass. The lack of published studies on caching by bears may be due to the behavior being infrequently used and difficult to record. We encourage an increase, but also consistency, in future reporting, including specific descriptions of caching behavior.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"1 1","pages":"1 - 8"},"PeriodicalIF":1.3,"publicationDate":"2021-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88921259","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 : 2021-07-01DOI: 10.2192/URSUS-D-20-00022.3
C. Tattoni, N. Bragalanti, M. Ciolli, C. Groff, F. Rovero
Abstract: The rubbing of trees by bears is an example of scent-marking that has been studied only in a limited number of bear species in the world. Our study analyzes the marking behavior of the European brown bear (Ursus arctos), based on filming by remote cameras placed in front of 25 rub trees in the central Italian Alps during 2012 to 2014. We obtained 546 videos of bears from a sampling effort of 9,302 camera-days. The bears captured in the videos were classified according to age and sex, and type and duration of each behavior was recorded. The data allowed us to assess temporal patterns of rubbing behavior and differences within sex, age, and among individuals. Rubbing was performed significantly more by adult males, with a peak during the breeding season. Adult males also used a variety of positions to mark the trees as compared with the other sex–age classes. Rubbing also was observed during the nonbreeding season, but with lower frequency, whereas investigation of rub trees was performed by bears of all ages and sexes throughout the seasons. The only 3 female bears that rubbed the trees were recorded in autumn, outside the breeding season. The results showed that scent-marking triggered a response in individuals that subsequently passed by the same rub tree; in 62% of the cases, the second bear either rubbed or investigated the tree, regardless of the time since the passage of the first bear. Our results supported the hypothesis that tree-rubbing during the breeding season is a means of communication, as already documented for brown bears and American black bears (U. americanus) in North America, but the function of this display outside the breeding season remains unclear.
{"title":"Behavior of the European brown bear at rub trees","authors":"C. Tattoni, N. Bragalanti, M. Ciolli, C. Groff, F. Rovero","doi":"10.2192/URSUS-D-20-00022.3","DOIUrl":"https://doi.org/10.2192/URSUS-D-20-00022.3","url":null,"abstract":"Abstract: The rubbing of trees by bears is an example of scent-marking that has been studied only in a limited number of bear species in the world. Our study analyzes the marking behavior of the European brown bear (Ursus arctos), based on filming by remote cameras placed in front of 25 rub trees in the central Italian Alps during 2012 to 2014. We obtained 546 videos of bears from a sampling effort of 9,302 camera-days. The bears captured in the videos were classified according to age and sex, and type and duration of each behavior was recorded. The data allowed us to assess temporal patterns of rubbing behavior and differences within sex, age, and among individuals. Rubbing was performed significantly more by adult males, with a peak during the breeding season. Adult males also used a variety of positions to mark the trees as compared with the other sex–age classes. Rubbing also was observed during the nonbreeding season, but with lower frequency, whereas investigation of rub trees was performed by bears of all ages and sexes throughout the seasons. The only 3 female bears that rubbed the trees were recorded in autumn, outside the breeding season. The results showed that scent-marking triggered a response in individuals that subsequently passed by the same rub tree; in 62% of the cases, the second bear either rubbed or investigated the tree, regardless of the time since the passage of the first bear. Our results supported the hypothesis that tree-rubbing during the breeding season is a means of communication, as already documented for brown bears and American black bears (U. americanus) in North America, but the function of this display outside the breeding season remains unclear.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"37 1","pages":"1 - 11"},"PeriodicalIF":1.3,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77113999","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 : 2021-06-08DOI: 10.2192/URSUS-D-20-00015.2
A. Karamanlidis, N. Panagiotopoulos
Abstract: Understanding animal behavior is essential for the conservation of endangered species. We document the case of a female brown bear (Ursus arctos) burying her 2 cubs-of-the-year, following their death in a car accident in May 2020 in the Prefecture of Kastoria, northern Greece. Both cubs were partially buried, half-covered with earth in an open field. We explore the circumstances and causes of this unusual behavior in relation to 2 potential explanations: caching of food and ‘grieving.’ Although the evidence collected is not conclusive enough to accept either of the 2 explanations, we report this observation to draw attention to this type of behavior in brown bears in the wild and hope that it will serve as a source for motivating future research.
{"title":"Burying of dead cubs by a brown bear in Greece: Food caching or ‘grief’ behavior?","authors":"A. Karamanlidis, N. Panagiotopoulos","doi":"10.2192/URSUS-D-20-00015.2","DOIUrl":"https://doi.org/10.2192/URSUS-D-20-00015.2","url":null,"abstract":"Abstract: Understanding animal behavior is essential for the conservation of endangered species. We document the case of a female brown bear (Ursus arctos) burying her 2 cubs-of-the-year, following their death in a car accident in May 2020 in the Prefecture of Kastoria, northern Greece. Both cubs were partially buried, half-covered with earth in an open field. We explore the circumstances and causes of this unusual behavior in relation to 2 potential explanations: caching of food and ‘grieving.’ Although the evidence collected is not conclusive enough to accept either of the 2 explanations, we report this observation to draw attention to this type of behavior in brown bears in the wild and hope that it will serve as a source for motivating future research.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"15 1","pages":"1 - 5"},"PeriodicalIF":1.3,"publicationDate":"2021-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76852254","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 : 2021-06-08DOI: 10.2192/URSUS-D-20-00023.2
K. Lomac-MacNair, Sheyna S. Wisdom, José Pedro De Andrade, J. Stepanuk, E. Esteves
Abstract: Evaluating the impacts of anthropogenic activities on Arctic wildlife is a key issue in current management and conservation strategies. With global climate change, expanding shipping routes, and increasing industrial development in the Arctic, the polar bear (Ursus maritimus) faces new challenges to its survival. Polar bear behavioral response to vessel presence is not well-documented. During the 2008–2014 Chukchi Sea Environmental Studies Program (CSESP), polar bear occurrence and behavioral data were collected during summer–autumn vessel surveys. We examined polar bear occurrence and behavioral response to vessel presence by distance. During this study, 56,901 km of observation effort occurred from 3 survey vessels and 42 groups (50 individuals) of polar bears were recorded. Over half of the groups exhibited a behavioral response (i.e., vigilance or flee) including all groups of mothers with cubs. The mean distance at which bears responded to vessels (805 ± 648 m) was closer than the mean distance at which no response was observed (2,001 ± 1,368 m). Logistic regression analysis revealed that response was associated with distance and our model indicated the estimated distance at which 50% of the polar bears would exhibit a behavioral response to be 1,645 m. Our findings are relevant to assess potential impacts of increasing vessel activity in the Arctic and to assist in the development of effective monitoring and mitigation strategies for polar bears.
{"title":"Polar bear behavioral response to vessel surveys in northeastern Chukchi Sea, 2008–2014","authors":"K. Lomac-MacNair, Sheyna S. Wisdom, José Pedro De Andrade, J. Stepanuk, E. Esteves","doi":"10.2192/URSUS-D-20-00023.2","DOIUrl":"https://doi.org/10.2192/URSUS-D-20-00023.2","url":null,"abstract":"Abstract: Evaluating the impacts of anthropogenic activities on Arctic wildlife is a key issue in current management and conservation strategies. With global climate change, expanding shipping routes, and increasing industrial development in the Arctic, the polar bear (Ursus maritimus) faces new challenges to its survival. Polar bear behavioral response to vessel presence is not well-documented. During the 2008–2014 Chukchi Sea Environmental Studies Program (CSESP), polar bear occurrence and behavioral data were collected during summer–autumn vessel surveys. We examined polar bear occurrence and behavioral response to vessel presence by distance. During this study, 56,901 km of observation effort occurred from 3 survey vessels and 42 groups (50 individuals) of polar bears were recorded. Over half of the groups exhibited a behavioral response (i.e., vigilance or flee) including all groups of mothers with cubs. The mean distance at which bears responded to vessels (805 ± 648 m) was closer than the mean distance at which no response was observed (2,001 ± 1,368 m). Logistic regression analysis revealed that response was associated with distance and our model indicated the estimated distance at which 50% of the polar bears would exhibit a behavioral response to be 1,645 m. Our findings are relevant to assess potential impacts of increasing vessel activity in the Arctic and to assist in the development of effective monitoring and mitigation strategies for polar bears.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"2009 1","pages":"1 - 14"},"PeriodicalIF":1.3,"publicationDate":"2021-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82526951","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 : 2021-05-03DOI: 10.2192/URSUS-D-19-0008.1
Daisuke Fujiki
Abstract: This study analyzed how 3 Fagaceae species (Fagus crenata, Quercus crispula, and Q. serrata) affect the occurrence of Asiatic black bears (Ursus thibetanus) in and around residential areas from generalized linear mixed models based on monitoring data of bear occurrence and masting over 14 years (2005–2018) in municipalities in Hyogo Prefecture, Japan. The constructed models suggest that it is important to consider the effects of mast production by multiple dominant Fagaceae species, not only within a municipality but also in the surrounding area, to predict bear occurrence with practical accuracy at the municipal level. The accuracy of the predictive model increased as the number of Fagaceae species in the model increased. Models differed among municipalities in their accuracy to predict bear occurrence, which was related to the effect of F. crenata mast production, which was correlated with the proportion of F. crenata forests in each municipality. I suggest that the accuracy of prediction at the municipal level depended on the effect of F. crenata mast production because the spatial and temporal synchrony of F. crenata mast production was stronger than that of other species. To take preventive action to reduce conflict between humans and bears, it would be useful to construct a model to predict bear occurrence at the municipal level based on monitoring data of mast production in multiple Fagaceae species.
{"title":"A model to predict the occurrence of Asiatic black bears at the municipal level using mast production data","authors":"Daisuke Fujiki","doi":"10.2192/URSUS-D-19-0008.1","DOIUrl":"https://doi.org/10.2192/URSUS-D-19-0008.1","url":null,"abstract":"Abstract: This study analyzed how 3 Fagaceae species (Fagus crenata, Quercus crispula, and Q. serrata) affect the occurrence of Asiatic black bears (Ursus thibetanus) in and around residential areas from generalized linear mixed models based on monitoring data of bear occurrence and masting over 14 years (2005–2018) in municipalities in Hyogo Prefecture, Japan. The constructed models suggest that it is important to consider the effects of mast production by multiple dominant Fagaceae species, not only within a municipality but also in the surrounding area, to predict bear occurrence with practical accuracy at the municipal level. The accuracy of the predictive model increased as the number of Fagaceae species in the model increased. Models differed among municipalities in their accuracy to predict bear occurrence, which was related to the effect of F. crenata mast production, which was correlated with the proportion of F. crenata forests in each municipality. I suggest that the accuracy of prediction at the municipal level depended on the effect of F. crenata mast production because the spatial and temporal synchrony of F. crenata mast production was stronger than that of other species. To take preventive action to reduce conflict between humans and bears, it would be useful to construct a model to predict bear occurrence at the municipal level based on monitoring data of mast production in multiple Fagaceae species.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"44 1","pages":"1 - 11"},"PeriodicalIF":1.3,"publicationDate":"2021-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76202106","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 : 2021-04-21DOI: 10.2192/URSUS-D-19-00029.1
M. Barrett, Najah J. Harriel, Sarah E. Barrett
Abstract: Measuring the body mass of American black bears (Ursus americanus) can be challenging because of their large size, and if equipment to weigh individuals is undersupplied. Our purpose was to estimate body mass of Florida black bears (U. a. floridanus) by developing models (linear and non-linear) that use morphometrics that can be reasonably easy to obtain (e.g., chest girth and body length). We compared our models with a previously published model for Florida black bears to determine whether prediction of body mass could be improved. Our models were built with current data (2012–2018; n = 532) collected across Florida, USA, by the Florida Fish and Wildlife Conservation Commission. We partitioned the data into training and test subsets using 10-fold cross-validation with 100 iterations. Model fit was assessed by comparing root mean square error (RMSE), mean absolute error (MAE), and coefficient of determination (R2) of observed and predicted values. Based on RMSE, MAE, and R2, our optimal regression model for predicting mass (M) of both female and male bears used both chest girth (G) and total body length (L) as predictors in the non-linear form M = aGb × Lc. Our optimal model was a better fit than the previously published model when both were applied to the full data sets from the current and previous study and to an independent data set. We applied our optimal non-linear regression models built from live bear data to morphological data collected from bear carcasses (n = 544), mainly road mortalities. We found that the live-bear models acceptably estimated mass of dead bears for both sexes. Estimating the mass of live and dead bears can expedite handling time of individuals, fill in data gaps, and provide valuable information on the Florida black bear; our approach may be applicable to American black bears range-wide.
{"title":"Improving estimates of body mass in American black bears using morphometrics and non-linear models","authors":"M. Barrett, Najah J. Harriel, Sarah E. Barrett","doi":"10.2192/URSUS-D-19-00029.1","DOIUrl":"https://doi.org/10.2192/URSUS-D-19-00029.1","url":null,"abstract":"Abstract: Measuring the body mass of American black bears (Ursus americanus) can be challenging because of their large size, and if equipment to weigh individuals is undersupplied. Our purpose was to estimate body mass of Florida black bears (U. a. floridanus) by developing models (linear and non-linear) that use morphometrics that can be reasonably easy to obtain (e.g., chest girth and body length). We compared our models with a previously published model for Florida black bears to determine whether prediction of body mass could be improved. Our models were built with current data (2012–2018; n = 532) collected across Florida, USA, by the Florida Fish and Wildlife Conservation Commission. We partitioned the data into training and test subsets using 10-fold cross-validation with 100 iterations. Model fit was assessed by comparing root mean square error (RMSE), mean absolute error (MAE), and coefficient of determination (R2) of observed and predicted values. Based on RMSE, MAE, and R2, our optimal regression model for predicting mass (M) of both female and male bears used both chest girth (G) and total body length (L) as predictors in the non-linear form M = aGb × Lc. Our optimal model was a better fit than the previously published model when both were applied to the full data sets from the current and previous study and to an independent data set. We applied our optimal non-linear regression models built from live bear data to morphological data collected from bear carcasses (n = 544), mainly road mortalities. We found that the live-bear models acceptably estimated mass of dead bears for both sexes. Estimating the mass of live and dead bears can expedite handling time of individuals, fill in data gaps, and provide valuable information on the Florida black bear; our approach may be applicable to American black bears range-wide.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"C-21 1","pages":"1 - 9"},"PeriodicalIF":1.3,"publicationDate":"2021-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85076839","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 : 2021-04-01DOI: 10.2192/URSUS-D-19-00036.2
R. V. Van Horn, James K. Sheppard, R. Swaisgood, R. Appleton, R. Sanchez, D. Vallejos, Javier Vallejos, M. Owen
Abstract: Natal dens are critical for reproduction in bears, yet we know virtually nothing of Andean bear (Tremarctos ornatus) denning ecology, nor whether female Andean bears select dens or den sites with specific characteristics. We analyzed data from 2008 to 2013 on characteristics of 8 natal dens (shelter and surroundings within 5 m) and den sites (context at ≥50 m from den) used by 4–5 females, with 21 potential (suitable but unused) natal dens and 30 potential den sites in the equatorial dry forest of Cerro Venado, Lambayeque, Peru. All observed natal dens were preexisting cavities under rocks, <5 m from a cliff. Natal dens had 1–2 entrances that varied in diameter (mean ± SE = 66.3 ± 9.01 cm). Maximum resting dimension within these dens was >2 m (242.3 ± 32.97 cm) and minimum vertical height within the resting area was <1.5 m (71.0 ± 10.93 cm). We found no evidence that female Andean bears preferred natal dens with any of the measured characteristics. Thus, if females in this area are selective when seeking a natal den, they are selective based on den site characteristics. All natal den sites were <50 m from a cliff and at relatively high elevations for this study area (887.8 ± 73.73 m above sea level). Sites were relatively steep (37.4 ± 6.38°), rugged (168.4 ± 26.29), and not obviously close to water (0.9 ± 0.21 km). Variables based on elevation and slope best described female use of natal den sites. Food, water, and solar heating seemed not to affect use of sites. Our results suggest that topographic resistance to travel by humans and other large mammals affects natal den site use in this area, and possibly elsewhere. The relevant topographical characteristics can be evaluated remotely, so conservation planners can model where natal den sites may occur in other habitats.
{"title":"Site characteristics influence Andean bear natal-den selection in dry forest habitat","authors":"R. V. Van Horn, James K. Sheppard, R. Swaisgood, R. Appleton, R. Sanchez, D. Vallejos, Javier Vallejos, M. Owen","doi":"10.2192/URSUS-D-19-00036.2","DOIUrl":"https://doi.org/10.2192/URSUS-D-19-00036.2","url":null,"abstract":"Abstract: Natal dens are critical for reproduction in bears, yet we know virtually nothing of Andean bear (Tremarctos ornatus) denning ecology, nor whether female Andean bears select dens or den sites with specific characteristics. We analyzed data from 2008 to 2013 on characteristics of 8 natal dens (shelter and surroundings within 5 m) and den sites (context at ≥50 m from den) used by 4–5 females, with 21 potential (suitable but unused) natal dens and 30 potential den sites in the equatorial dry forest of Cerro Venado, Lambayeque, Peru. All observed natal dens were preexisting cavities under rocks, <5 m from a cliff. Natal dens had 1–2 entrances that varied in diameter (mean ± SE = 66.3 ± 9.01 cm). Maximum resting dimension within these dens was >2 m (242.3 ± 32.97 cm) and minimum vertical height within the resting area was <1.5 m (71.0 ± 10.93 cm). We found no evidence that female Andean bears preferred natal dens with any of the measured characteristics. Thus, if females in this area are selective when seeking a natal den, they are selective based on den site characteristics. All natal den sites were <50 m from a cliff and at relatively high elevations for this study area (887.8 ± 73.73 m above sea level). Sites were relatively steep (37.4 ± 6.38°), rugged (168.4 ± 26.29), and not obviously close to water (0.9 ± 0.21 km). Variables based on elevation and slope best described female use of natal den sites. Food, water, and solar heating seemed not to affect use of sites. Our results suggest that topographic resistance to travel by humans and other large mammals affects natal den site use in this area, and possibly elsewhere. The relevant topographical characteristics can be evaluated remotely, so conservation planners can model where natal den sites may occur in other habitats.","PeriodicalId":49393,"journal":{"name":"Ursus","volume":"10 1","pages":"1 - 14"},"PeriodicalIF":1.3,"publicationDate":"2021-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86594916","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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