black bears
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2022 ◽  
Author(s):  
Babar Zahoor ◽  
Xuehua Liu ◽  
Basharat Ahmad

Abstract The Asiatic black bear is considered an indicator species of the environment, hence, any change in the environment may alter its activity pattern. We monitored the monthly activity pattern of black bears in the moist temperate forests of Machiara National Park, AJ&K, Pakistan. We used infrared camera traps and indigenous knowledge for data collection from April 2019 to April 2021. Camera traps recorded 109 (inside the forest = 107, outside the forest = 2) independent registrations (IR) within 5541 (692.63 ± 36.72, mean ± SD) camera days. We found that (i) spring and autumn were the lowest activity seasons of black bears inside the forest. (ii) Whereas, the highest activities were recorded in summer with peak activities in August followed by July (χ2 = 203.5, df= 7, P< 0.05). (iii) The activity level sharply declined after August and halted from late November to late April which was clear indication of bears’ hibernation period. We collected indigenous knowledge from 70 selected persons, including hunters, herders, temporary residents and crop raiding victims. We used the data of human observation of latest three years and found that (i) bears remained active from May to November and hibernated rest of the period. (ii) The activities were at their peak inside the forest in summer (May – August) and out of the forest in autumn (September – November) when it preferred to raid the widely cultivated maize crop (Zea mays) in the area. The capturing of black bears by camera traps outside the forest further supported the data provided by local people. Such switching over might have occurred due to the food preferences for Zea mays or easy access to abundant food availability out of the forest area. The current data can help mitigate human black bears conflict and consequently future conservation of black bears in the area.


2022 ◽  
Author(s):  
Dusit Ngoprasert ◽  
Robert Steinmetz ◽  
Kriangsak Sribuarod ◽  
George A. Gale
Keyword(s):  

Ursus ◽  
2021 ◽  
Vol 2021 (32e24) ◽  
Author(s):  
Yoh Ogawa ◽  
Kahoko Tochigi ◽  
Tomoko Naganuma ◽  
Bainah S. Dewi ◽  
Shinsuke Koike
Keyword(s):  

Ursus ◽  
2021 ◽  
Vol 2021 (32e23) ◽  
Author(s):  
Muhammad Naeem Awan ◽  
Muhammad Sidique Awan ◽  
Muhammad Ali Nawaz ◽  
Shoab Hameed ◽  
Muhammad Kabir ◽  
...  
Keyword(s):  

2021 ◽  
Author(s):  
Naomi X Louchouarn ◽  
Adrian Treves

Abstract Given the ecological importance of top predators, societies are turning to non-lethal methods for coexistence. Coexistence is challenging when livestock are released within wild predator habitats, even when people supervise or use lethal methods. We report a randomized, controlled design to evaluate low-stress livestock handling (L-SLH), a form of range riding, to deter grizzly (brown) bears, gray wolves, cougars, black bears, and coyotes in Southwestern Alberta. The treatment condition was supervision by two newly hired and trained range riders and an L-SLH practicing range rider. This treatment was compared against a baseline pseudo-control condition of the single experienced range rider working alone. Cattle experienced zero injuries or deaths in either condition. We infer that inexperienced range riders trained and supervised by an experienced rider did not raise or lower the risk to cattle. Also, predators did not shift to the cattle herds protected by fewer range riders. Pending experimental evaluation of other designs, we recommend use of L-SLH.


Nature ◽  
2021 ◽  
Author(s):  
Ellison J. McNutt ◽  
Kevin G. Hatala ◽  
Catherine Miller ◽  
James Adams ◽  
Jesse Casana ◽  
...  

AbstractBipedal trackways discovered in 1978 at Laetoli site G, Tanzania and dated to 3.66 million years ago are widely accepted as the oldest unequivocal evidence of obligate bipedalism in the human lineage1–3. Another trackway discovered two years earlier at nearby site A was partially excavated and attributed to a hominin, but curious affinities with bears (ursids) marginalized its importance to the paleoanthropological community, and the location of these footprints fell into obscurity3–5. In 2019, we located, excavated and cleaned the site A trackway, producing a digital archive using 3D photogrammetry and laser scanning. Here we compare the footprints at this site with those of American black bears, chimpanzees and humans, and we show that they resemble those of hominins more than ursids. In fact, the narrow step width corroborates the original interpretation of a small, cross-stepping bipedal hominin. However, the inferred foot proportions, gait parameters and 3D morphologies of footprints at site A are readily distinguished from those at site G, indicating that a minimum of two hominin taxa with different feet and gaits coexisted at Laetoli.


2021 ◽  
pp. 104063872110611
Author(s):  
Kristin A. Clothier ◽  
Katherine D. Watson ◽  
Aslı Mete ◽  
Federico Giannitti ◽  
Mark Anderson ◽  
...  

From 2014–2019, 8 juvenile black bears ( Ursus americanus) from different geographic regions were presented to the California Department of Fish and Wildlife because of emaciation, alopecia, and exfoliative dermatitis that resulted in death or euthanasia. Autopsy and histopathology revealed that all 8 bears had generalized hyperkeratotic dermatitis, folliculitis, and furunculosis. Skin structures were heavily colonized by fungal hyphae and arthrospores; fungal cultures of skin from 7 bears yielded Trichophyton equinum, a zoophilic dermatophyte reported only rarely in non-equid species. Additional skin conditions included mites (5), ticks (2), and coagulase-negative Staphylococcus sp. infections (2). No other causes of morbidity or mortality were identified. Molecular comparisons performed at the University of Texas Fungal Reference Laboratory determined that all isolates produced identical banding patterns, potentially representing a clonal population. Dermatophytosis is commonly localized and limited to the stratum corneum of the epidermis and hair follicles. Generalized disease with dermal involvement is rare in immunocompetent individuals; illness, malnutrition, age, or immunosuppression may increase susceptibility. Underlying causes for the severe disease impact in these bears were not evident after physical or postmortem examination. The mechanism by which bears from different geographic locations had severe, T. equinum–associated dermatophytosis from a potentially clonal dermatophyte could not be explained and warrants further investigation.


2021 ◽  
Author(s):  
◽  
Maximilian L. Allen

<p>Large carnivores are important components of many ecosystems and play an integral role in determining the composition and structure of ecological communities. The influences of pumas (Puma concolor) on other species, including prey and competitors, vary across their range and among individuals. I used novel methodologies, including intensive real-time GPS investigations of potential kill sites using ARGOS satellite collars, and motion-triggered video cameras to study the intra- and inter-specific interactions of pumas and understand their influences on ecological communities. Results from my dissertation support previous findings that pumas play an integral role in shaping their respective ecosystem, but that pumas are also influenced substantially by their local environment. Overall, my dissertation highlights the importance of understanding intra- and inter-specific interactions of large carnivores when attempting to understand their influences on ecological communities. I tested whether pumas exhibited sexual variation in their use of communication behaviours at community scrape areas, and what factors influenced their mating strategies. I found that males more frequently exhibited and spent longer durations on ‘producing’ behaviours (scraping and body rubbing), while females more frequently exhibited and spent longer durations on ‘consuming’ behaviours (olfactory investigation and flehmen response behaviours). This suggests that male reproductive strategy is based on advertisement for possible mates, while female reproductive strategy is based on assessment of potential mates. Pumas also exhibited sexual variation in their patterns of visitation. Males were regular visitors, while females were irregular visitors whose visitation cycles were apparently correlated with oestrus. Mate selection by females was complex and based on multiple cues, the two most important of which were the visitation rate and mass of males. The frequency of male visits and the display of some behaviours were influenced most by visits from female pumas, but were also influenced by visits from competing males. I used real-time and fine-scale GPS location data to find prey killed by individual pumas, and analysed seasonal patterns to understand local influences on puma behaviour and feeding ecology. I found that black-tailed deer (Odocoileus hemionus columbianus) were the main prey of pumas, constituting 98.6% of their diet by mass, and that the elevations at which pumas killed black-tailed deer correlated significantly with seasonal elevations used by black-tailed deer. I found pumas had relatively high ungulate kill rates ( ̅ = 1.07 ungulates/week, and ̅ = 5.78 kg/day), and that kill rates in ungulates/week varied among seasons and were highest in summer and autumn. Importantly, the handling times of black-tailed deer >1 year old showed an inverse seasonal relationship with kill rates in ungulates/week, and the lower handling times may have been due to black bear kleptoparasitism. These findings suggest that puma feeding ecology can be strongly influenced by seasonal behaviour of their prey and dominant scavengers. Given the potential for large carnivores to influence scavengers, I studied the influences of both pumas and black bears on the scavenger community. I found that pumas and black bears were a source of limitation for scavengers, both on the species richness and sum feeding times of the scavenger community, as well as the occurrence, total feeding times, and mean feeding bout durations of scavenger species. However, pumas had some positive influences, for example they facilitated the acquisition of carrion by scavengers, and they apparently initiated a cascading pattern that led to an increase in the acquisition of carrion by small carnivores. In contrast, black bears, as dominant scavengers, monopolized carrion resources and substantially limited the acquisition of carrion by other scavengers, and in fact they had larger limitations for scavengers than pumas as top-level predators. The influences on carrion acquisition suggest that large carnivores have important influences on the scavenger community, and their influences could be a mechanism for the effects large carnivores have on community composition.</p>


2021 ◽  
Author(s):  
◽  
Maximilian L. Allen

<p>Large carnivores are important components of many ecosystems and play an integral role in determining the composition and structure of ecological communities. The influences of pumas (Puma concolor) on other species, including prey and competitors, vary across their range and among individuals. I used novel methodologies, including intensive real-time GPS investigations of potential kill sites using ARGOS satellite collars, and motion-triggered video cameras to study the intra- and inter-specific interactions of pumas and understand their influences on ecological communities. Results from my dissertation support previous findings that pumas play an integral role in shaping their respective ecosystem, but that pumas are also influenced substantially by their local environment. Overall, my dissertation highlights the importance of understanding intra- and inter-specific interactions of large carnivores when attempting to understand their influences on ecological communities. I tested whether pumas exhibited sexual variation in their use of communication behaviours at community scrape areas, and what factors influenced their mating strategies. I found that males more frequently exhibited and spent longer durations on ‘producing’ behaviours (scraping and body rubbing), while females more frequently exhibited and spent longer durations on ‘consuming’ behaviours (olfactory investigation and flehmen response behaviours). This suggests that male reproductive strategy is based on advertisement for possible mates, while female reproductive strategy is based on assessment of potential mates. Pumas also exhibited sexual variation in their patterns of visitation. Males were regular visitors, while females were irregular visitors whose visitation cycles were apparently correlated with oestrus. Mate selection by females was complex and based on multiple cues, the two most important of which were the visitation rate and mass of males. The frequency of male visits and the display of some behaviours were influenced most by visits from female pumas, but were also influenced by visits from competing males. I used real-time and fine-scale GPS location data to find prey killed by individual pumas, and analysed seasonal patterns to understand local influences on puma behaviour and feeding ecology. I found that black-tailed deer (Odocoileus hemionus columbianus) were the main prey of pumas, constituting 98.6% of their diet by mass, and that the elevations at which pumas killed black-tailed deer correlated significantly with seasonal elevations used by black-tailed deer. I found pumas had relatively high ungulate kill rates ( ̅ = 1.07 ungulates/week, and ̅ = 5.78 kg/day), and that kill rates in ungulates/week varied among seasons and were highest in summer and autumn. Importantly, the handling times of black-tailed deer >1 year old showed an inverse seasonal relationship with kill rates in ungulates/week, and the lower handling times may have been due to black bear kleptoparasitism. These findings suggest that puma feeding ecology can be strongly influenced by seasonal behaviour of their prey and dominant scavengers. Given the potential for large carnivores to influence scavengers, I studied the influences of both pumas and black bears on the scavenger community. I found that pumas and black bears were a source of limitation for scavengers, both on the species richness and sum feeding times of the scavenger community, as well as the occurrence, total feeding times, and mean feeding bout durations of scavenger species. However, pumas had some positive influences, for example they facilitated the acquisition of carrion by scavengers, and they apparently initiated a cascading pattern that led to an increase in the acquisition of carrion by small carnivores. In contrast, black bears, as dominant scavengers, monopolized carrion resources and substantially limited the acquisition of carrion by other scavengers, and in fact they had larger limitations for scavengers than pumas as top-level predators. The influences on carrion acquisition suggest that large carnivores have important influences on the scavenger community, and their influences could be a mechanism for the effects large carnivores have on community composition.</p>


2021 ◽  
Vol 107 (3) ◽  
pp. 202-212
Author(s):  
Robert J. Schaefer ◽  
Dennis Moyles ◽  
Steven McDonald ◽  
Monty Cervelli ◽  
Daniel Beck

Black bear (Ursus americanus) populations in California have increased in abundance and distribution despite rising trends in the urban encroachment of wildlands. As human-black bear conflicts increase, opportunities to study the relocation of black bears in an adaptive management setting are important for improving the management of this highprofile species. Habituated black bears, some tamed and made tractable through human-controlled food conditioning, were relocated to a remote region of the Klamath Mountains to analyze home range use, survival, return rates, and mortality. Relocated black bears with known outcomes demonstrated an 80% return rate, with 55% not surviving beyond five months. Female bears established home ranges significantly larger than males, and may suggest an enhanced maternal instinct in search of similar nutritional conditions prior to relocation. This study showed that the relocation of food-conditioned black bears resulted in high return rates, poor survival, and risk to public safety.


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