Regulation of mitochondrial metabolism by hibernating bear serum: Insights into seasonal metabolic adaptations.

Hibernating animals undergo a unique and reversible decrease in their whole-body metabolism, which is often accompanied by a suppression of mitochondrial respiration. However, the precise mechanisms underlying these seasonal shifts in mitochondrial metabolism remain unclear. In this study, the effect of the serum from active and hibernating Japanese black bears on mitochondrial respiration was assessed. Stromal-vascular cells were obtained from bear white adipose tissue and cultured with or without an adipocyte differentiation cocktail. When the oxygen consumption was measured in the presence of bear serum, the hibernating bear serum reduced maximal respiration by 15.5 % (p < 0.05) and spare respiratory capacity by 46.0 % (p < 0.01) in the differentiated adipocytes in comparison to the active bear serum. Similar reductions of 23.4 % (p = 0.06) and 40.6 % (p < 0.05) respectively were observed in undifferentiated cells, indicating the effect is cell type-independent. Blue native PAGE analysis revealed that hibernating bear serum suppressed cellular metabolism independently of the assembly of mitochondrial respiratory chain complexes. RNA-seq analysis identified 1094 differentially expressed genes (fold change>1.5, FDR<0.05) related to insulin signaling and glucose metabolism pathways. These findings suggest that the rapid alterations in mitochondrial metabolism during hibernation are likely induced by a combination of reduced insulin signaling and suppressed mitochondrial function, rather than changes in respiratory complex assembly.

Plant species richness at archaeological sites suggests ecological legacy of Indigenous subsistence on the Colorado Plateau.

Humans have both intentional and unintentional impacts on their environment, yet identifying the enduring ecological legacies of past small-scale societies remains difficult, and as such, evidence is sparse. The present study found evidence of an ecological legacy that persists today within an semiarid ecosystem of western North America. Specifically, the richness of ethnographically important plant species is strongly associated with archaeological complexity and ecological diversity at Puebloan sites in a region known as Bears Ears on the Colorado Plateau. A multivariate model including both environmental and archaeological predictors explains 88% of the variation in ethnographic species richness (ESR), with growing degree days and archaeological site complexity having the strongest effects. At least 31 plant species important to five tribal groups (Navajo, Hopi, Zuni, Ute Mountain Ute, and Apache), including the Four Corners potato (Solanum jamesii), goosefoot (Chenopodium sp.), wolfberry (Lycium pallidum), and sumac (Rhus trilobata), occurred at archaeological sites, despite being uncommon across the wider landscape. Our results reveal a clear ecological legacy of past human behavior: even when holding environmental variables constant, ESR increases significantly as a function of past investment in habitation and subsistence. Consequently, we suggest that propagules of some species were transported and cultivated, intentionally or not, establishing populations that persist to this day. Ensuring persistence will require tribal input for conserving and restoring archaeo-ecosystems containing "high-priority" plant species, especially those held sacred as lifeway medicines. This transdisciplinary approach has important implications for resource management planning, especially in areas such as Bears Ears that will experience greater visitation and associated impacts in the near future.

Influenza A(H5N1) Virus Infections in 2 Free-Ranging Black Bears (Ursus americanus), Quebec, Canada.

Wholly Eurasian highly pathogenic avian influenza H5N1 clade 2.3.4.4b virus was isolated from 2 free-ranging black bears with meningoencephalitis in Quebec, Canada. We found that isolates from both animals had the D701N mutation in the polymerase basic 2 gene, previously known to promote adaptation of H5N1 viruses to mammal hosts.

Body mass is associated with hibernation length, body temperature, and heart rate in free-ranging brown bears.

BACKGROUND: Despite centuries of research, debate remains on the scaling of metabolic rate to mass especially for intraspecific cases. The high variation of body mass within brown bears presents a unique opportunity to study the intraspecific effects of body mass on physiological variables. The amplitude of metabolic rate reduction in hibernators is dependent on body mass of the species. Small hibernators have high metabolic rates when euthermic but experience a drastic decrease in body temperature during torpor, which is necessary to reach a very low metabolic rate. Conversely, large hibernators, such as the brown bear (Ursus arctos), show a moderate decrease in temperature during hibernation, thought to be related to the bear's large size. We studied body mass, abdominal body temperature, heart rate, and accelerometer-derived activity from 63 free-ranging brown bears (1-15 years old, 15-233 kg). We tested for relationships between body mass and body temperature, heart rate, and hibernation duration. RESULTS: The smallest individuals maintained lower body temperatures during hibernation, hibernated longer, and ended hibernation later than large bears. Unlike body temperature, winter heart rates were not associated with body mass. In summer, the opposite pattern was found, with smaller individuals having higher body temperature and daytime heart rates. Body mass was associated with body temperature in the winter hypometabolic state, even in a large hibernating mammal. Smaller bears, which are known to have higher thermal conductance, reached lower body temperatures during hibernation. During summer, smaller bears had higher body temperatures and daytime heart rates, a phenomenon not previously documented within a single mammalian species. CONCLUSION: We conclude that the smallest bears hibernated more deeply and longer than large bears, likely from a combined effect of basic thermodynamics, the higher need for energy savings, and a lower cost of warming up a smaller body.

Bone adaptation and osteoporosis prevention in hibernating mammals.

Hibernating bears and rodents have evolved mechanisms to prevent disuse osteoporosis during the prolonged physical inactivity that occurs during hibernation. Serum markers and histological indices of bone remodeling in bears indicate reduced bone turnover during hibernation, which is consistent with organismal energy conservation. Calcium homeostasis is maintained by balanced bone resorption and formation since hibernating bears do not eat, drink, urinate, or defecate. Reduced and balanced bone remodeling protect bear bone structure and strength during hibernation, unlike the disuse osteoporosis that occurs in humans and other animals during prolonged physical inactivity. Conversely, some hibernating rodents show varying degrees of bone loss such as osteocytic osteolysis, trabecular loss, and cortical thinning. However, no negative effects of hibernation on bone strength in rodents have been found. More than 5000 genes in bear bone tissue are differentially expressed during hibernation, highlighting the complexity of hibernation induced changes in bone. A complete picture of the mechanisms that regulate bone metabolism in hibernators still alludes us, but existing data suggest a role for endocrine and paracrine factors such as cocaine- and amphetamine-regulated transcript (CART) and endocannabinoid ligands like 2-arachidonoyl glycerol (2-AG) in decreasing bone remodeling during hibernation. Hibernating bears and rodents evolved the capacity to preserve bone strength during long periods of physical inactivity, which contributes to their survival and propagation by allowing physically activity (foraging, escaping predators, and mating) without risk of bone fracture following hibernation. Understanding the biological mechanisms regulating bone metabolism in hibernators may inform novel treatment strategies for osteoporosis in humans.

Lions and brown bears colonized North America in multiple synchronous waves of dispersal across the Bering Land Bridge.

The Bering Land Bridge connecting North America and Eurasia was periodically exposed and inundated by oscillating sea levels during the Pleistocene glacial cycles. This land connection allowed the intermittent dispersal of animals, including humans, between Western Beringia (far northeast Asia) and Eastern Beringia (northwest North America), changing the faunal community composition of both continents. The Pleistocene glacial cycles also had profound impacts on temperature, precipitation and vegetation, impacting faunal community structure and demography. While these palaeoenvironmental impacts have been studied in many large herbivores from Beringia (e.g., bison, mammoths, horses), the Pleistocene population dynamics of the diverse guild of carnivorans present in the region are less well understood, due to their lower abundances. In this study, we analyse mitochondrial genome data from ancient brown bears (Ursus arctos; n = 103) and lions (Panthera spp.; n = 39), two megafaunal carnivorans that dispersed into North America during the Pleistocene. Our results reveal striking synchronicity in the population dynamics of Beringian lions and brown bears, with multiple waves of dispersal across the Bering Land Bridge coinciding with glacial periods of low sea levels, as well as synchronous local extinctions in Eastern Beringia during Marine Isotope Stage 3. The evolutionary histories of these two taxa underline the crucial biogeographical role of the Bering Land Bridge in the distribution, turnover and maintenance of megafaunal populations in North America.

Widespread male sex bias in mammal fossil and museum collections.

A recent study of mammoth subfossil remains has demonstrated the potential of using relatively low-coverage high-throughput DNA sequencing to genetically sex specimens, revealing a strong male-biased sex ratio [P. Pecnerová et al., Curr. Biol. 27, 3505-3510.e3 (2017)]. Similar patterns were predicted for steppe bison, based on their analogous female herd-based structure. We genetically sexed subfossil remains of 186 Holarctic bison (Bison spp.), and also 91 brown bears (Ursus arctos), which are not female herd-based, and found that ∼75% of both groups were male, very close to the ratio observed in mammoths (72%). This large deviation from a 1:1 ratio was unexpected, but we found no evidence for sex differences with respect to DNA preservation, sample age, material type, or overall spatial distribution. We further examined ratios of male and female specimens from 4 large museum mammal collections and found a strong male bias, observable in almost all mammalian orders. We suggest that, in mammals at least, 1) wider male geographic ranges can lead to considerably increased chances of detection in fossil studies, and 2) sexual dimorphic behavior or appearance can facilitate a considerable sex bias in fossil and modern collections, on a previously unacknowledged scale. This finding has major implications for a wide range of studies of fossil and museum material.

The acute physiological response of polar bears to helicopter capture.

Many wildlife species are live captured, sampled, and released; for polar bears (Ursus maritimus) capture often requires chemical immobilization via helicopter darting. Polar bears reduce their activity for approximately 4 days after capture, likely reflecting stress recovery. To better understand this stress, we quantified polar bear activity (via collar-mounted accelerometers) and body temperature (via loggers in the body core [Tabd] and periphery [Tper]) during 2-6 months of natural behavior, and during helicopter recapture and immobilization. Recapture induced bouts of peak activity higher than those that occurred during natural behavior for 2 of 5 bears, greater peak Tper for 3 of 6 bears, and greater peak Tabd for 1 of 6 bears. High body temperature (>39.0°C) occurred in Tper for 3 of 6 individuals during recapture and 6 of 6 individuals during natural behavior, and in Tabd for 2 of 6 individuals during recapture and 3 of 6 individuals during natural behavior. Measurements of Tabd and Tper correlated with rectal temperatures measured after immobilization, supporting the use of rectal temperatures for monitoring bear response to capture. Using a larger dataset (n = 66 captures), modeling of blood biochemistry revealed that maximum ambient temperature during recapture was associated with a stress leukogram (7-26% decline in percent lymphocytes, 12-21% increase in percent neutrophils) and maximum duration of helicopter operations had a similar but smaller effect. We conclude that polar bear activity and body temperature during helicopter capture are similar to that which occurs during the most intense events of natural behavior; high body temperature, especially in warm capture conditions, is a key concern; additional study of stress leukograms in polar bears is needed; and additional data collection regarding capture operations would be useful.

Multispecies facial detection for individual identification of wildlife: a case study across ursids.

To address biodiversity decline in the era of big data, replicable methods of data processing are needed. Automated methods of individual identification (ID) via computer vision are valuable in conservation research and wildlife management. Rapid and systematic methods of image processing and analysis are fundamental to an ever-growing need for effective conservation research and practice. Bears (ursids) are an interesting test system for examining computer vision techniques for wildlife, as they have variable facial morphology, variable presence of individual markings, and are challenging to research and monitor. We leveraged existing imagery of bears living under human care to develop a multispecies bear face detector, a critical part of individual ID pipelines. We compared its performance across species and on a pre-existing wild brown bear Ursus arctos dataset (BearID), to examine the robustness of convolutional neural networks trained on animals under human care. Using the multispecies bear face detector and retrained sub-applications of BearID, we prototyped an end-to-end individual ID pipeline for the declining Andean bear Tremarctos ornatus. Our multispecies face detector had an average precision of 0.91-1.00 across all eight bear species, was transferable to images of wild brown bears (AP = 0.93), and correctly identified individual Andean bears in 86% of test images. These preliminary results indicate that a multispecies-trained network can detect faces of a single species sufficiently to achieve high-performance individual classification, which could speed-up the transferability and application of automated individual ID to a wider range of taxa. Supplementary Information: The online version contains supplementary material available at 10.1007/s42991-021-00168-5.

Tardigrada: An Emerging Animal Model to Study the Endoplasmic Reticulum Stress Response to Environmental Extremes.

Tardigrada (also known as "water bears") are hydrophilous microinvertebrates with a bilaterally symmetrical body and four pairs of legs usually terminating with claws. Water bears are quite complex animals and range from 50 to 1200 µm in length. Their body is divided into a head segment and four trunk segments, each bearing a pair of legs. They inhabit almost all terrestrial and aquatic environments, from the ocean depths to highest mountains ranges. However, one of their best known and unusual features is their capability for cryptobiosis. In this state tardigrades are able to survive extremely low and high temperatures and atmospheric pressures, complete lack of water, high doses of radiation, high concentrations of toxins and even a cosmic vacuum. The cellular mechanisms enabling cryptobiosis are poorly understood, although it appears the synthesis of certain types of molecules (sugars and proteins) enable the prevention of cellular damage at different levels. The endoplasmic reticulum (ER) is a morphologically and functionally diverse organelle able to integrate multiple extracellular and internal signals and generate adaptive cellular responses. However, the ER morphology and activity in the case of tardigrades has been studied rarely and in the context of oogenesis, functioning of the digestive system, and in the role and function of storage cells. Thus, there are no direct studies on the contribution of the ER in the ability of this organism to cope with environmental stress during cryptobiosis. Nevertheless, it is highly probable that the ER has a crucial role in this uncommon process. Since water bears are easy to handle laboratory animals, they may represent an ideal model organism to uncover the important role of the ER in the cell response to extreme environmental stress conditions.

Artificial night light helps account for observer bias in citizen science monitoring of an expanding large mammal population.

The integration of citizen scientists into ecological research is transforming how, where, and when data are collected, and expanding the potential scales of ecological studies. Citizen-science projects can provide numerous benefits for participants while educating and connecting professionals with lay audiences, potentially increasing the acceptance of conservation and management actions. However, for all the benefits, collection of citizen-science data is often biased towards areas that are easily accessible (e.g. developments and roadways), and thus data are usually affected by issues typical of opportunistic surveys (e.g. uneven sampling effort). These areas are usually illuminated by artificial light at night (ALAN), a dynamic sensory stimulus that alters the perceptual world for both humans and wildlife. Our goal was to test whether satellite-based measures of ALAN could improve our understanding of the detection process of citizen-scientist-reported sightings of a large mammal. We collected observations of American black bears Ursus americanus (n = 1,315) outside their primary range in Minnesota, USA, as part of a study to gauge population expansion. Participants from the public provided sighting locations of bears on a website. We used an occupancy modelling framework to determine how well ALAN accounted for observer metrics compared to other commonly used metrics (e.g. housing density). Citizen scientists reported 17% of bear sightings were under artificially lit conditions and monthly ALAN estimates did the best job accounting for spatial bias in detection of all observations, based on AIC values and effect sizes ( ß^  = 0.81, 0.71-0.90 95% CI). Bear detection increased with elevated illuminance; relative abundance was positively associated with natural cover, proximity to primary bear range and lower road density. Although the highest counts of bear sightings occurred in the highly illuminated suburbs of the Minneapolis-St. Paul metropolitan region, we estimated substantially higher bear abundance in another region with plentiful natural cover and low ALAN (up to ~375% increased predicted relative abundance) where observations were sparse. We demonstrate the importance of considering ALAN radiance when analysing citizen-scientist-collected data, and we highlight the ways that ALAN data provide a dynamic snapshot of human activity.

Evidence for human-caused founder effect in populations of Solanum jamesii found at archaeological sites: I. Breeding experiments and the geography of sexual reproduction.

PREMISE: Plant domestication can be detected when transport, use, and manipulation of propagules impact reproductive functionality, especially in species with self-incompatible breeding systems. METHODS: Evidence for human-caused founder effect in the Four Corners potato (Solanum jamesii Torr.) was examined by conducting 526 controlled matings between archaeological and non-archaeological populations from field-collected tubers grown in a greenhouse. Specimens from 24 major herbaria and collection records from >160 populations were examined to determine which produced fruits. RESULTS: Archaeological populations did not produce any fruits when self-crossed or outcrossed between individuals from the same source. A weak ability to self- or outcross within populations was observed in non-archaeological populations. Outcrossing between archaeological and non-archaeological populations, however, produced fully formed, seed-containing fruits, especially with a non-archaeological pollen source. Fruit formation was observed in 51 of 162 occurrences, with minimal evidence of constraint by monsoonal drought, lack of pollinators, or spatial separation of suitable partners. Some archaeological populations (especially those along ancient trade routes) had records of fruit production (Chaco Canyon), while others (those in northern Arizona, western Colorado, and southern Utah) did not. CONCLUSIONS: The present study suggests that archaeological populations could have different origins at different times-some descending directly from large gene pools to the south and others derived from gardens already established around occupations. The latter experienced a chain of founder events, which presumably would further reduce genetic diversity and mating capability. Consequently, some archaeological populations lack the genetic ability to sexually reproduce, likely as the result of human-caused founder effect.

Treatment of two Asiatic black bears (Ursus thibetanus) with severe injuries and their subsequent release into the wild: a case report.

BACKGROUND: The rehabilitation of injured wildlife and their subsequent release into the wild is a humane act as well as important in wildlife conservation. However, little is known about the animals' fate after release. Therefore, to address these uncertainties, it is essential to adequately describe how the injured animals were treated and managed before releasing into the wild; moreover, post-release monitoring should also be performed. Herein, we document for the first time the process of rescue, surgery, and rehabilitation of severely injured Asiatic black bears (Ursus thibetanus; endangered species in South Korea) and their fate after returning to the wild. CASE PRESENTATION: A six-year-old female (bear-01) and a three-year-old male (bear-02) bears were injured by an illegal snare and collision with a bus, respectively. Bear-01 had broad muscle necrosis and ruptures from the snared ankle on the right thoracic limb, with myiasis, and elbow disarticulation was performed. In bear-02, a non-reducible comminuted fracture of the left humerus was confirmed radiologically, and the operation was performed by using dual plate fixation with hydroxyapatite and recombinant human bone morphogenetic protein-2. The bear-01 and -02 were completely healed approximately 30 and 60 days after surgery, respectively. After that, they underwent rehabilitation for 8 and 25 days, respectively, in an outdoor enclosure similar to their natural habitat. Bear-01 and -02 were released into the wild after 45 and 99 days after surgery, respectively, and their mean daily movement distance during the first 30 days after releasing was 2.9 ± 2.1 and 1.3 ± 1.6 km, respectively. The annual mean 95% Kernel home-range size of bear-01 and bear-02 was 265.8 and 486.9 km2, respectively. They hibernated every winter, gained weight, gave birth to cubs (bear-01), were not found to have any abnormalities in the veterinary tests, and were not involved in any conflicts with humans after returning to the wild. CONCLUSIONS: Bears without one leg or those with dual plates could adapt well in their natural habitat, which shows that our surgical and post-operative treatments were effective. Additionally, minimizing human contact and observing/evaluating behavior during the rehabilitation is essential in reducing human-bear conflicts after release.

Response of grizzly bears (Ursus arctos) to pipelines in Alberta.

This research provides the first in-depth analysis of fine-scale grizzly bear habitat selection and movement patterns in response to the linear footprints cleared for below-ground pipelines in Alberta. Using an extensive set of GPS location data from collared grizzly bears, we were able to determine that grizzly bears selected for younger pipelines (mean age since last construction~6.5 years), which are known to have a greater abundance of important bear foods. Bears also selected for wider corridors that were disturbed for construction more than once. During the spring season, sex/age class was an important predictor of grizzly bear use of pipelines, with adult female bears more likely to use these features than other sex/age classes. Examination of movement patterns revealed that pipeline density influenced grizzly bears' movement rates and path straightness, particularly in the spring, when bears moved more slowly and movement paths were more tortuous in areas with higher pipeline densities. These movement patterns are consistent with foraging behavior and further indicate that bears are not exhibiting avoidance behaviors or displacement by pipeline features, and pipelines may be functioning as seasonally important foraging areas for grizzly bears in Alberta.

Changing spring snow cover dynamics and early season forage availability affect the behavior of a large carnivore.

Changing climates are altering wildlife habitats and wildlife behavior in complex ways. Here, we examine how changing spring snow cover dynamics and early season forage availability are altering grizzly bear (Ursus arctos) behavior postden emergence. Telemetry data were used to identify spring activity dates for 48 individuals in the Yellowhead region of Alberta, Canada. Spring activity date was related to snow cover dynamics using a daily percent snow cover dataset. Snow melt end date, melt rate, and melt consistency explained 45% of the variation in spring activity date. We applied this activity date model across the entire Yellowhead region from 2000 to 2016 using simulated grizzly bear home ranges. Predicted spring activity date was then compared with a daily spring forage availability date dataset, resulting in "wait time" estimates for four key early season forage species. Temporal changes in both spring activity date and early season forage "wait times" were assessed using non-parametric regression. Grizzly bear activity date was found to have either remained constant (95%) or become earlier (5%) across the study area; virtually no areas with significantly later spring activity dates were detected. Similarly, the majority of "wait times" did not change (85%); however, the majority of significant changes in "wait times" for the four early season forage species indicated that "wait times" were lessening where changes were detected. Our results show that spring activity date is largely dictated by snow melt characteristics and that changing snow melt conditions may result in earlier spring activity. However, early season food stress conditions are likely to remain unchanged or improve as vegetation phenology also becomes earlier. Our findings extend the recent work examining animal movement in response to changing phenology from migratory birds and ungulates to an apex predator, further demonstrating the potential effects of changing climates on wildlife species.

Three-dimensional dental topography and feeding ecology in the extinct cave bear.

The cave bear (Ursus spelaeus s.l.) was an iconic extinct bear that inhabited the Pleistocene of Eurasia. The cause of extinction of this species is unclear and to identify the actual factors, it is crucial to understand its feeding preferences. Here, we quantified the shape descriptor metrics in three-dimensional (3D) models of the upper teeth (P4-M2) of the cave bear to make inferences about its controversial feeding behaviour. We used comparative samples, including representatives of all living bear species with known diets, as a template. Our topographic analyses show that the complexity of upper tooth rows in living bears is more clearly associated with the mechanical properties of the items consumed than with the type of food. Cave bears exhibit intermediate values on topographic metrics compared with the bamboo-feeder giant panda (Ailuropoda melanoleuca) and specialists in hard mast consumption (Ursus arctos and Ursus thibetanus). The crown topography of cave bear upper teeth suggests that they could chew on tough vegetal resources of low quality with high efficiency, a characteristic that no living bear currently displays. Our results align with a climate-driven hypothesis to explain the extinction of cave bear populations during the Late Pleistocene.

Psychological drivers of risk-reducing behaviors to limit human-wildlife conflict.

Conflicts between people and wild animals are increasing globally, often with serious consequences for both. Local regulations or ordinances are frequently used to promote human behaviors that minimize these conflicts (risk-reducing behaviors), but compliance with ordinances can be highly variable. While efforts to increase compliance could be improved through applications of conservation psychology, little is known about the relative influence of different factors motivating compliance. Using concepts from psychology and risk theory, we conducted a longitudinal study pairing data from mail surveys with direct observations of compliance with a wildlife ordinance requiring residents to secure residential garbage from black bears (Ursus americanus). We assessed the relative influence of beliefs and attitudes toward bears and bear proofing, perceived behavioral control, perceived risks and benefits assigned to bears, norms, trust in management, previous experience with conflicts, and demographics on compliance behavior (i.e., bear proofing). Data on previous experience were obtained through direct observation and survey reports. We found that higher compliance rates were associated with more observed conflicts on a respondent's block. Counter to expectations, however, residents were less compliant when they were more trusting of the management agency and perceived more benefits from bears. We suggest that messages have the potential to increase compliance when they empower residents by linking successful management of conflicts to individual actions and emphasize how reducing conflicts could maintain benefits provided by wildlife. Modifying existing educational materials to account for these psychological considerations and evaluating their impact on compliance behavior over time are important next steps in changing human behaviors relevant to the globally important problem of human-wildlife conflict.

Impulsores Psicológicos de los Comportamientos Reductores de Riesgo para Limitar el Conflicto Humano - Fauna Resumen Los conflictos entre las personas y la fauna cada vez son más a nivel mundial y con frecuencia tienen consecuencias severas para ambos. Las regulaciones o decretos locales se usan frecuentemente para promover comportamientos humanos que minimizan estos conflictos (comportamientos reductores de riesgo), pero el cumplimiento de los decretos puede ser altamente variable. Mientras que los esfuerzos por incrementar el cumplimiento podrían mejorar por medio de la aplicación de la psicología de la conservación, se conoce poco sobre la influencia relativa de los diferentes factores que motivan al cumplimiento. Realizamos un estudio longitudinal mediante conceptos tomados de la psicología y la teoría del riesgo. Este estudio emparejó datos obtenidos de encuestas por correo con observaciones directas del cumplimiento de un decreto de fauna que requiere que los residentes protejan los desechos residenciales de los osos negros (Ursus americanus) (es decir, hacerlas a prueba de osos). Evaluamos la influencia relativa de las creencias y las actitudes hacia los osos y hacia hacer los desechos a prueba de osos, el control del comportamiento percibido, los riesgos percibidos y los beneficios asignados a los osos, las normas, la confianza en el manejo, la experiencia previa con conflictos y la demografía del comportamiento de cumplimiento. Los datos sobre la experiencia previa se obtuvieron mediante observación directa y reportes de las encuestas. Encontramos que las tasas más altas de cumplimiento estuvieron asociadas con un mayor número de conflictos observados en la cuadra del respondiente. Sin embargo, contrario a las expectativas, los residentes fueron menos obedientes cuando tuvieron mayor confianza en la agencia de manejo y percibieron más beneficios de la presencia de osos. Sugerimos que los mensajes tienen el potencial de incrementar el cumplimiento cuando empoderan a los residentes al vincular el manejo exitoso de los conflictos con las acciones individuales y enfatizan cómo la reducción de los conflictos podría mantener los beneficios que proporciona la fauna. La modificación de los materiales educativos existentes para que tomen en cuenta estas consideraciones psicológicas y la evaluación de su impacto sobre el comportamiento de cumplimiento a lo largo del tiempo son los siguientes pasos importantes para modificar el comportamiento humano relevante para el problema mundialmente importante que es el conflicto humano - fauna.

Regulation of metabolism during hibernation in brown bears (Ursus arctos): Involvement of cortisol, PGC-1α and AMPK in adipose tissue and skeletal muscle.

The purpose of this study was to investigate changes in expression of known cellular regulators of metabolism during hyperphagia (Sept) and hibernation (Jan) in skeletal muscle and adipose tissue of brown bears and determine whether signaling molecules and transcription factors known to respond to changes in cellular energy state are involved in the regulation of these metabolic adaptations. During hibernation, serum levels of cortisol, glycerol, and triglycerides were elevated, and protein expression and activation of AMPK in skeletal muscle and adipose tissue were reduced. mRNA expression of the co-activator PGC-1α was reduced in all tissues in hibernation whereas mRNA expression of the transcription factor PPAR-α was reduced in the vastus lateralis muscle and adipose tissue only. During hibernation, gene expression of ATGL and CD36 was not altered; however, HSL gene expression was reduced in adipose tissue. During hibernation gene expression of the lipogenic enzyme DGAT in all tissues and the expression of the FA oxidative enzyme LCAD in the vastus lateralis muscle were reduced. Gene and protein expression of the glucose transporter GLUT4 was decreased in adipose tissue in hibernation. Our data suggest that high cortisol levels are a key adaptation during hibernation and link cortisol to a reduced activation of the AMPK/PGC-1α/PPAR-α axis in the regulation of metabolism in skeletal muscle and adipose tissue. Moreover, our results indicate that during this phase of hibernation at a time when metabolic rate is significantly reduced metabolic adaptations in peripheral tissues seek to limit the detrimental effects of unduly large energy dissipation.

Molecular detection of apicomplexan protozoa in Hokkaido brown bears (Ursus arctos yesoensis) and Japanese black bears (Ursus thibetanus japonicus).

Many tick-borne pathogens (TBPs) are present in wildlife. The objective of this study is to reveal the role of wild bears in maintaining TBPs. A total of 49 brown bears (Ursus arctos yesoensis) from Hokkaido, and 18 Japanese black bears (Ursus thibetanus japonicus) from Tochigi, and 66 Japanese black bears from Nagano were examined by two molecular methods, reverse line blot (RLB) hybridization, and nested PCR. A total of 5 TBPs (Hepatozoon ursi, Babesia sp. UR2-like group, Cytauxzoon sp. UR1, Babesia sp. UR1, and Babesia microti) were detected from bear blood DNA samples. B. microti was detected from blood DNA samples of Japanese black bear for the first time, with the prevalence of 6.0% (5/84). Out of detected pathogens, H. ursi, Babesia sp. UR2-like pathogens, and Cytauxzoon sp. UR1 were considered as three of the most prevalent TBPs in bears. The prevalence of H. ursi were significantly higher in Japanese black bear (0% vs 96.4%) while that of Babesia sp. UR2-like group was higher in Hokkaido brown bears (89.8% vs 40.5%). The prevalence of Babesia sp. UR1 were significantly higher in Japanese black bears from Tochigi (44.4%), comparing with those from Nagano (18.2%). The prevalence of the detected TBPs were significantly higher in adult bears, comparing with those in younger bears. The present study suggests that Japanese bear species contribute in the transmission of several TBPs in Japan. The expanding distribution of bears might cause the accidental transmission of TBPs to humans and domestic animals.

Seroprevalence, DNA isolation, and genetic characterization of Toxoplasma gondii from black bear (Ursus americanus) sera collected in Eastern Oklahoma.

Black bears (Ursus americanus) are commonly exposed to Toxoplasma gondii. However, there are no reports of exposure or infection with T. gondii in black bears from Oklahoma. The purpose of our project was to determine the seroprevalence of T. gondii antibodies in black bears collected in Oklahoma. Additionally, since only serum was available from these bears, we sought to determine if DNA extraction and PCR amplification for T. gondii was possible on serum samples from bears with positive titers. Seroprevalence was determined using modified agglutination test (MAT). Serum was collected from 44 live-trapped bears in southeastern Oklahoma; 32 (73% ± 58-84%) had antibodies against T. gondii. Seroprevalence in adult bears (85% ± 67-95%) was significantly higher (p = 0.028) than yearlings (33.0% ± 56-80%). Adult bears were 3.4 times more likely to have antibodies to T. gondii than yearlings. From the bears with positive titers, T. gondii DNA was detected in 12 of the 32 seropositive samples by PCR of the B1 gene, with two of the samples showing variation in two nucleotide positions when compared with available sequences. Multilocus PCR-RFLP genotyping of these 12 samples revealed three ToxoDB genotypes, including #2 (type III, haplogroup 3), #4 (type XII, haplogroup 12), and #74 (haplogroup 12). To the best of our knowledge, this is the first report of T. gondii seroprevalence in black bears from Oklahoma. Our results indicate that exposure and infection with T. gondii in black bears from Oklahoma is common.