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Feline Panleukopenia Virus in a Marsican Brown Bear and Crested Porcupine, Italy, 2022–2023
The virus species Protoparvovirus carnivoran 1 encompasses pathogens that infect both domestic and wild carnivores, including feline panleukopenia virus. We identified and characterized feline panleukopenia virus strains in a Marsican brown bear (Ursus arctos marsicanus) and a crested porcupine (Hystrix cristata) in Italy, extending the known host range of this virus.
Journal Article
Septic Arthritis and Osteomyelitis in Finger Caused by Mycoplasma phocimorsus from Brown Bear, Alaska, USA
Mycoplasma phocimorsus is an identified zoonotic agent of musculoskeletal infections. Osteomyelitis developed in a patient after injury sustained while skinning a bear, and he experienced delayed diagnosis after ineffective treatments. Clinicians should use doxycycline or moxifloxacin therapy in treatment-refractory cases with exposure to seals, cats, or bears while awaiting molecular diagnostics results.
Journal Article
Large carnivores under assault in Alaska
In Alaska, gray wolves (Canis lupis), brown bears (Ursus arctos), and black bears (U. americanus) are managed in most of the state in ways intended to significantly reduce their abundance in the expectation of increasing hunter harvests of ungulates. To our knowledge, Alaska is unique in the world because this management priority is both widespread and mandated by state law. Large carnivore management in Alaska is a reversion to outdated management concepts and occurs without effective monitoring programs designed to scientifically evaluate impacts on predator populations. Large carnivore management in Alaska should be based on rigorous science including the status and trends of carnivore populations.
Journal Article
Bears and berries: species-specific selective foraging on a patchily distributed food resource in a human-altered landscape
When animals are faced with extraordinary energyconsuming events, like hibernation, finding abundant, energy-rich food resources becomes particularly important. The profitability of food resources can vary spatially, depending on occurrence, quality, and local abundance. Here, we used the brown bear (Ursus arctos) as a model species to quantify selective foraging on berries in different habitats during hyperphagia in autumn prior to hibernation. During the peak berry season in August and September, we sampled berry occurrence, abundance, and sugar content, a proxy for quality, at locations selected by bears for foraging and at random locations in the landscape. The factors determining selection of berries were species specific across the different habitats. Compared to random locations, bears selected locations with a higher probability of occurrence and higher abundance of bilberries (Vaccinium myrtillus) and a higher probability of occurrence, but not abundance, of lingonberries (Vaccinium vitis-idaea). Crowberries (Empetrum hermaphroditum) were least available and least used. Sugar content affected the selection of lingonberries, but not of bilberries. Abundance of bilberries at random locations decreased and abundance of lingonberries increased during fall, but bears did not adjust their foraging strategy by increasing selection for lingonberries. Forestry practices had a large effect on berry occurrence and abundance, and brown bears responded by foraging most selectively in mature forests and on clearcuts. This study shows that bears are successful in navigating human-shaped forest landscapes by using areas of higher than average berry abundance in a period when abundant food intake is particularly important to increase body mass prior to hibernation. Significance statement Food resources heterogeneity, caused by spatial and temporal variation of specific foods, poses a challenge to foragers, particularly when faced with extraordinary energy-demanding events, like hibernation. Brown bears in Sweden inhabit a landscape shaped by forestry practices. Bilberries and lingonberries, the bears’ main food resources in autumn prior to hibernation, show different temporal and habitat-specific ripening patterns. We quantified the bears’ selective foraging on these berry species on clearcuts, bogs, young, and mature forests compared to random locations. Despite a temporal decline of ripe bilberries, bears used locations with a greater occurrence and abundance of bilberries, but not lingonberries. We conclude that bears successfully navigated in this heavily human-shaped landscape by selectively foraging in highreturn habitats for bilberries, but did not compensate for the decline in bilberries by eating more lingonberries.Bilberry . Brown bear . Lingonberry . Movement trajectories . Optimal foraging . Sugar content
Journal Article
Macronutrient optimization and energy maximization determine diets of brown bears
Many animals consume mixed diets that maximize their fitness by optimizing macronutrient intake. We tested whether brown bears (Ursus arctos), generalist omnivores that hibernate, regulated their diet to a common nutrient target, achieved a nutrient target related to fitness, and selected a nutrient target that differed between seasons and from other species with differing life histories. When given unlimited access to 2 or 3 highly digestible foods containing primarily protein, carbohydrate, or lipid, brown bears selected mixed diets in which protein provided 17% ± 4% SD of the metabolizable energy and 22% ± 6% of the dry matter. This dietary protein content maximized the rate of gain per unit of energy consumed, is similar to the level preferred by other omnivores, and is less than that preferred by obligate carnivores. Between seasons, bears selected similar dietary protein levels, although the proportion of lipid was higher during the fall than during the spring. Bears strongly preferred lipids over carbohydrates, as did other carnivores, but they used lipids and carbohydrates with equal efficiency to produce a dietary protein content that maximized mass gain per unit of energy intake. Thus, dietary sources of lipids and carbohydrates play an interchangeable and important role in determining the productivity of bears that goes beyond their role in providing energy.
Journal Article
Living with a large predator: Assessing the root causes of Human–brown bear conflict and their spatial patterns in Lahaul valley, Himachal Pradesh
Brown bear‐mediated conflicts have caused immense economic loss to the local people living across the distribution range. In India, limited knowledge is available on the Himalayan brown bear (HBB), making human–brown bear conflict (HBC) mitigation more challenging. In this study, we studied HBC in the Lahaul valley using a semi‐structured questionnaire survey by interviewing 398 respondents from 37 villages. About 64.8% of respondents reported conflict in two major groups—crop damage (30.6%) and livestock depredations (6.2%), while 28% reported both. Conflict incidences were relatively high in summer and frequently occurred in areas closer to the forest (<500 m) and between the elevations range of 2700 m to 3000 m above sea level (asl). The dependency of locals on forest resources (70%) for their livelihood makes them vulnerable to HBC. The “upper lower” class respondents were most impacted among the various socioeconomic classes. Two of the four clusters were identified as HBC hot spots in Lahaul valley using SaTscan analysis. We also obtained high HBC in cluster II with a 14.35 km radius. We found that anthropogenic food provisioning for HBB, livestock grazing in bear habitats, and poor knowledge of animal behavior among the communities were the major causes of HBC. We suggest horticulture crop waste management, controlled and supervised grazing, ecotourism, the constitution of community watch groups, and others to mitigate HBC. We also recommend notifying a few HBB abundant sites in the valley as protected areas for the long‐term viability of the HBB in the landscape. 1. About 64.8% of respondents reported conflict into two major groups ‐ crop damage (31.4%) and livestock depredations (6.2%) and were relatively high in summer and frequently occurred in areas closer forest between the 2700m to 3000m asl. We identified four clusters of HBC, and the hotspots lies in clusters 2 and 4. #10; #10;2. We found that anthropogenic food provisioning of bears, livestock grazing in bear habitats and poor knowledge of animal behaviour among the communities are the major causes of HBC. #10;3. We suggest proper disposal of horticulture crop waste, mass awareness among communities, controlled and supervised grazing as an immediate management strategy to reduce the HBC.
Journal Article
Hibernation and seasonal fasting in bears: the energetic costs and consequences for polar bears
Global warming has the potential to reduce arctic sea ice and thereby increase the length of summer–fall fasting when polar bears (Ursus maritimus) lose access to most marine mammals. To evaluate the consequences of such changes, we compared the cost of fasting by polar bears with hibernation by brown bears (U. arctos), American black bears (U. americanus), and polar bears and made projections about tissue reserves polar bears will need to survive and reproduce as fasts become longer. Hibernating polar bears expend energy at the same rate per unit mass as do brown bears and black bears. However, daily mass losses, energy expenditures, and the losses of lean mass are much higher in fasting, active polar bears than in hibernating bears. The average pregnant polar bear living around Hudson Bay during the 1980s and 1990s could fast for 10.0 ± 2.3 months (X̄ ± SD), and the average lactating female with cubs born during the preceding winter could fast for 4.2 ± 1.9 months. Thus, some pregnant or lactating females with lower levels of body fat content were already approaching or beyond the constraint of being able to produce cubs and survive the required 8 months of fasting if producing new offspring or 4 months if accompanied by older offspring. Pregnant or lactating females and their dependent offspring have the most tenuous future as global warming occurs. Thus, we predict a significant reduction in productivity with even modest increases in global warming for polar bears living in the very southern part of their range and are concerned about more northern populations depending on their ability to accumulate increasing amounts of fat.
Journal Article
Seasonal and annual variation in the food habits of Apennine brown bears, central Italy
Only scanty and outdated knowledge is available on the food habits of the Apennine brown bear (Ursus arctos marsicanus) population, despite its critical conservation status. Based on 2,359 scats, collected from June 2006 through December 2009, we documented seasonal and annual variation in the diet of this bear population within its 1,294-km2 core distribution in Abruzzo, Lazio, and Molise National Park and its external buffer area in central Italy. Using correction factors to estimate digestible energy, we revealed substantial consumption of plant matter by bears, including herbaceous vegetation in spring (mean ± SD; 31.7% ± 25%) and early summer (19.0% ± 7%), a variety of naturally occurring berries in summer (56.5% ± 14%), and hard mast (66.9% ± 21%), largely supplemented by fleshy fruits (26.3% ± 18%), in the fall. Bears also consumed insects, mostly ants, in early summer (38.3% ± 7%), and wild ungulates in spring (10.2% ± 11%). Hard mast production strongly influenced year-to-year variation in the diet. High-quality foods, such as berries and other fleshy fruits, were increasingly consumed by bears in years of low to null hard mast productivity, suggesting that habitat productivity is currently high and diversified enough to allow bears to avoid the risk of nutritional stress during occasional hard mast failures. Nevertheless, as exemplified by a negative trend in late-summer consumption of buckthorn (Rhamnus spp.) berries by bears, our findings demonstrate the need to implement management strategies that will ensure long-term habitat productivity and provide optimal foraging opportunities for Apennine brown bears.
Journal Article
Human Perceptions about the Himalayan Brown Bear and other Carnivores in Chitral District in the Hindu Kush Range, Pakistan
The Himalayan brown bear (Ursus arctos isabellinus) historically occupied the vast mountain ranges of South and Central Asia. Their range has shrunken significantly in the past century and they currently live in small and isolated populations. Most of their range has not been surveyed; hence information on their distribution is largely based on anecdotal information and expert judgments. The present study investigated the species’ current distribution in the Hindu Kush Range in Pakistan, gathering information on human-brown bear conflict along with other large carnivore species in the study area. Multiple survey techniques questionnaire surveys, sign surveys and camera trapping were used during the period 2008–2010 in five study blocks delineated on natural watersheds in Pakistan’s Chitral district. Based on questionnaire surveys, sign surveys and direct sighting, Himalayan brown bear presence was confirmed only in the Yarkhun and Laspur valleys. Ninety-six respondents (59 from Laspur Valley and 37 from Broghil Valley) reported a total of 449 livestock losses (90 heads per year) to carnivore species—grey wolf (Canis lupus), snow leopard (Panthera pardus), Himalayan lynx (Lynx lynx isabellinus)—during the five-year (2005–2009) period, which translated into an economic loss of USD 34,297 (PKR 2,931,022); USD 357 (PKR 30,531) per household. Himalayan brown bear was not accounted for any livestock loss. Though the public was seen to be strongly against large carnivores, brown bear was considered ‘less dangerous’. Despite limited conflict with humans, brown bear has lost a large part of its historical range in the Hindu Kush Range. The species is confined to the eastern valleys where it is maintaining connectivity with brown bear in Gilgit-Baltistan towards the east and with Afghan populations towards the west.
Journal Article