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1.
Sci Rep ; 14(1): 21600, 2024 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-39284845

RESUMO

Understanding how large carnivores utilize space is crucial for management planning in human-dominated landscape and enhances the accuracy of population size estimates. However, Eurasian lynx display a large inter-population variation in the size of home ranges across their European range which makes extrapolation to broader areas of a species distribution problematic. This study evaluates variations in home range size for 35 Eurasian lynx in the Western Carpathians during 2011-2022 based on GPS telemetry and explains how intrinsic and environmental factors shape lynx spatial behaviour when facing anthropogenic pressure. The average annual home range size of lynx ranged from 283 (± 42 SE) to 360 (± 60 SE) km2 for males and from 148 (± 50 SE) to 190 (± 70 SE) km2 for females, depending on home range estimator (95% MCP, KDE and AKDE). Females with kittens had smaller annual and summer home ranges compared to non-reproducing females and subadults had smaller home ranges compared to adults. Lynx home range size was explained by availability of roe deer, except for summer, when alternative prey was likely available. We also found clear evidence of human-induced changes in lynx home range size, in particular, forest cover significantly decreased the home range size of male lynx during summer while road density led to an expansion of both annual and summer lynx home ranges. Lynx exhibited consistent fidelity to their home ranges throughout consecutive seasons, showing no seasonal variations. Strong territoriality was observed among competing males maintaining relatively low home range overlaps and considerable distances between centres of activity. The most pronounced tendency for association was observed between males and females, maintaining relatively close proximity year-round. The insights into lynx spatial requirements provided by our study will greatly enhance the accuracy of population size estimates and effectiveness of mitigation measures across the Western Carpathians.


Assuntos
Comportamento de Retorno ao Território Vital , Lynx , Animais , Lynx/fisiologia , Feminino , Masculino , Comportamento de Retorno ao Território Vital/fisiologia , Ecossistema , Estações do Ano , Densidade Demográfica
2.
Front Nutr ; 11: 1467475, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39296504

RESUMO

Background: Very-low-carbohydrate diets, including ketogenic and carnivore diets, are gaining popularity for the experimental treatment of a wide range of disorders, including inflammatory bowel disease (IBD). Methods: Participants were recruited through a social media survey. Final inclusion required a histologically confirmed diagnosis of ulcerative colitis (UC) or Crohn's disease that was responsive to treatment with a ketogenic or carnivore diet without medication or with successful medication cessation on the diet. Clinical improvement was measured with the Inflammatory Bowel Disease Questionnaire (IBDQ). Results: We report on 10 cases of IBD responsive to ketogenic, mostly carnivore, diets. Clinical presentations were diverse, including six cases of UC and four of Crohn's disease. Clinical improvements were universal, with clinical improvement scores ranging between 72 and 165 points on the IBDQ. Patients' diets comprised mostly meat, eggs, and animal fats. Patients report their diets are pleasurable, sustainable, and unequivocally enhance their quality of life. Conclusion: Ketogenic and carnivore diets hold promise for the treatment of IBD, including UC and Crohn's disease. These cases are consistent with clinical literature that shows an inverse association between intestinal ketone levels and IBD activity, as well as the therapeutic effects of low residue elimination diets on colonic microbiota metabolism.

3.
Ecol Evol ; 14(9): e70228, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39219577

RESUMO

Successful conservation of expanding large carnivore populations and management of human-wildlife conflict to promote coexistence requires sufficient spatiotemporal knowledge to inform appropriate action. In Canada, cougars (Puma concolor) are expanding their range eastwards and little research is available for use in decision making by land managers and conservation planners. To inform proactive management regarding expanding populations of cougars in Canada, we utilized open-source cougar presence and land-cover data in a maximum entropy habitat suitability model to determine potentially suitable habitat for cougars across the country. We then used a gap analysis to determine the effectiveness of existing formal protected areas to protect potential cougar habitat. Suitable habitat exists for range-expanding cougars dispersing eastwards through the central and eastern provinces to the Atlantic coast. While the habitat is highly fragmented, the highest suitability occurs in areas of medium road density, indicating that the potential for new human-cougar conflict will likely involve residents of exurban and rural areas. Protected areas offered 16% coverage of suitable habitat, although most protected areas that overlap predicted cougar habitat are not large enough to effectively conserve the large home range requirements of cougars. Synthesis and Applications: High fragmentation of suitable habitat and the potential for human-wildlife conflict requires proactive management to ensure appropriately sized and connected areas are maintained for the establishment of expanding cougar populations. Many of the management actions intended to aid in the conservation of cougars and their habitat can also serve to mitigate potential human-cougar conflict arising as a consequence of an expanding population, such as highway wildlife crossing structures and formal habitat protection.

4.
Front Vet Sci ; 11: 1279844, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39220768

RESUMO

Fluralaner is a recent external parasiticide, first of a new class of drugs (isoxazoline parasiticides). It is widely used in companion animals both for its wide spectrum (fleas, ticks and other mites) but also for its ease of use (oral tablets given once for 1 to three months). It is known to be eliminated primarily via the feces (>90%) as the unchanged compound. In zoo carnivores, controlling external parasites is also important and there are no specific products with a marketing authorization to control them. The first objective of this study was to evaluate the pharmacokinetic profile of fluralaner in zoo carnivores. The second objective was to demonstrate that fluralaner can be eliminated over a prolonged period of time, thereby raising questions about its potential impact on non-target species such as arthropods. After adjusting the oral dose using allometric equations, animals were dosed and fecal samples were collected on a regular basis for up to three months to determine the fecal elimination curve of fluralaner as a surrogate of plasma kinetics (for ethical and safety reasons, plasma samples were not considered). All samples were analyzed with a validated LC-MSMS technique. Our results show that, despite limitations and a limited number of animals included, most carnivores eliminate fluralaner in their feces for several weeks to months (in Lions, fluralaner was still detectable after 89 days). To our knowledge, this is the first study demonstrating such a long elimination period in animals. Further studies would be required to investigate the risk associated with the presence of active residues in other carnivore feces for the environment, especially in dogs and cats, considering the large use of this class of compounds.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39262094

RESUMO

Through killing and instilling fear in their prey, large terrestrial carnivores shape the structure and function of ecosystems globally. Most large carnivore species have experienced severe range and population declines due to human activities, and many are now threatened with extinction. Consequently, the impacts of these predators on food webs have been diminished or lost completely from many ecosystems. Kill rates provide a fundamental metric for understanding large carnivore ecology and assessing and comparing predation within and across ecological communities. Our systematic review of large terrestrial mammalian carnivore kill rates reveals significant positive geographic (North America, Europe, and Africa) and taxonomic (grey wolf Canis lupus, puma Puma concolor, lion Panthera leo, and Eurasian lynx Lynx lynx) bias, with most studies apparently motivated by human-carnivore conflict over access to ungulate prey and wildlife management objectives. Our current understanding of the behaviour and functional roles of many large carnivore species and populations thus remains limited. By synthesising and comparing kill rates, we show that solitary carnivores (e.g. brown bears Ursus arctos and most felids) exhibit higher per capita kill rates than social carnivores. However, ungulate predation by bears is typically limited to predation of neonates during a short period. Lower per capita kill rates by social carnivores suggests group living significantly reduces energetic demands, or, alternatively, that group-living carnivores defend and consume a greater proportion of large prey carcasses, or may acquire more food through other means (e.g. scavenging, kleptoparasitism) than solitary hunters. Kill and consumption rates for Canidae - measured as kilograms of prey per kilogram of carnivore per day - are positively correlated with body mass, consistent with increasing energy costs associated with a cursorial hunting strategy. By contrast, ambush predators such as felids show an opposite trend, and thus the potential energetic advantage of an ambush hunting strategy for carnivores as body mass increases. Additionally, ungulate kill rates remain relatively constant across solitary felid body sizes, indicative of energetic constraints and optimal foraging. Kill rate estimates also reveal potential insights into trophic structuring within carnivore guilds, with subordinate carnivores often killing more than their larger counterparts, which may be indicative of having to cope with food losses to scavengers and dominant competitors. Subordinate carnivores may thus serve an important role in provisioning food to other trophic levels within their respective ecosystems. Importantly, kill rates also clarify misconceptions around the predatory behaviour of carnivores (e.g. spotted hyaenas Crocuta crocuta and wolverines Gulo gulo are often considered scavengers rather than the capable hunters that they are) and thus the potential impacts of various carnivore species on their ecological communities. Despite the importance of kill rates in understanding predator-prey interactions, their utility is not widely recognised, and insufficient research limits our ability to fully appreciate and predict the consequences of modified predation regimes, justify current management actions affecting carnivores, or inform effective conservation measures. Together with other important research on predator-prey interactions, robust kill rate studies that address the research deficiencies we highlight will provide a deeper understanding of the foraging behaviours and potential ecosystem impacts of many of the world's carnivores, thus aiding effective conservation and management actions.

6.
Animals (Basel) ; 14(17)2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39272326

RESUMO

The present study aimed to describe the skull and mandibles of the brown bear (U. arctos) from the Dancing Bear Belitsa Park using advanced 3D morpho-geometric techniques. The objective was to explore how sexual dimorphism and size influence cranial structures using advanced 3D geometric morphometric methods. Three-dimensional models of the skulls and mandibles of 12 brown bears were used. Differences in skull morphology between male and female brown bears were observed in this study. The male brown bear skull, larger than the female, exhibited a more pronounced extension of the upper part of the nuchal region towards the posterior. Additionally, the posterior part of the frontal region appeared notably thinner in male brown bears compared to females. Analysis of the mandible revealed that the masseteric fossa was more developed in males than females. These shape differences between males and females were found to be influenced by body size. Statistical analyses indicated a significant allometric effect of body size on skull PC1 values, suggesting that giant bears tend to have more elongated skulls. This implies a relationship in which larger individuals exhibit greater cranial elongation. In contrast, mandible PC1 values showed no size-related variation, indicating that mandibular shape is less influenced by overall body size. However, PC2 values in the mandible increased significantly with larger specimens, indicating a larger masseteric fossa in larger bears. This morphological adaptation potentially enhances feeding efficiency and bite strength in larger individuals, reflecting functional adaptations in brown-bear mandibular morphology. These findings contribute to our understanding of sexual dimorphism and size-related morphological adaptations in brown bears, providing insights into their adaptation biology and ecological roles within their habitats.

7.
Environ Evid ; 13(1): 13, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-39294801

RESUMO

BACKGROUND: Instances of attacks from large carnivores that lead to human injury or death are increasingly reported worldwide. Ensuring human safety when people and carnivores co-occur is central to minimizing human suffering but is also essential to support sustainable carnivore conservation. Various interventions are available intended to alter either the behavior of large carnivores or people, in order to reduce the likelihood of a risky encounter and an attack. Collated evidence on best practices is still lacking, and this protocol outlines a systematic review of evidence for intervention effectiveness to reduce the risk or severity of direct attacks on humans by large carnivores. Specifically, the review seeks to answer the question: How effective are evaluated interventions in reducing large carnivore attacks on people? METHODS: The bibliographic databases Zoological Record, BIOSIS Citation Index, and Scopus will be searched using a predefined search string. Grey literature will be requested through professional networks, contacts with relevant organizations, and searching selected websites. All returned titles and abstracts will be manually screened using Rayyan.ai. For inclusion, studies should describe the Population, Intervention, Comparator, and Outcome (PICO) of the review research question and be written in English, Spanish, or Swedish. Review papers will be excluded. All records of data coding and extraction are documented in a purposely developed, and priorly piloted, data sheet. Critical appraisal of study validity will be done according to the Collaboration for Environmental Evidence Critical Appraisal Tool prototype version 0.3. Review outcomes will be synthesized in a narrative, and if possible, a quantitative synthesis. The narrative synthesis will describe in text the carnivore population (species, location), context (target object, intervention model), as well as the design and reported results of each study. The quantitative synthesis will include a summary statistic, preferably logarithmic risk ratio, calculated for each original study. A forest plot will be created to visualize study outcomes, as well as judgments of critical appraisal. Provided that enough data is available and that it complies with its assumptions, a meta-regression analysis will be undertaken using metafor package for R software.

8.
Animals (Basel) ; 14(18)2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39335297

RESUMO

Human activities have resulted in severe habitat degradation and fragmentation at a global scale. Despite this scenario, some carnivore species that adapted to the new conditions are expanding, leading to close coexistence with humans and the emergence of potential conflicts. In this work, we used a European wildcat (Felis silvestris) observations database of more than 350 sightings over 17 years in NW Spain to build suitability models based on environmental, topographic, climatic, and human impact variables. MaxEnt was used to analyse the availability of suitable habitats for the species at a regional scale. Our results showed that less than one third of the suitable area for the species had confirmed wildcat presence. Elevation, the percentage of forested area, and footpath density were the three main variables conditioning wildcat presence, with the first two variables having positive effects and footpath density negatively affecting wildcat presence. The selection of high areas and forest areas by the species seems to be related to food availability, while the avoidance of footpaths seems to be related to the fact that main mortality causes are linked to human disturbances. The results enhance the understanding of the European wildcat ecology and provide insight into potential management plans to ensure the conservation of one of the main populations of the species throughout its range.

9.
Animals (Basel) ; 14(16)2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39199888

RESUMO

Since Darwin, many evolutionary and behavioral researchers have considered the role of phenotypic traits that favor the domestication of nonhuman animals. Among such proposed traits are a species' social structure, level of intra- and interspecific agonistic interactions, sociosexual behaviors, parental strategies, reaction to humans, habitat preference, dietary habits, developmental trajectories, and utility to humans. However, little to no comparative phylogenetic evidence exists concerning the importance of these attributes for the domestication of animals. Moreover, rather than considering domestication as a dichotomous event (non-domesticated vs. domesticated), humans and their potential domesticates encountered numerous socioecological challenges/obstacles during the domestication process before reaching the stage of full domestication. The present study explored the influence of adult body mass, gregariousness, dietary breadth, and reaction to humans on the domestication process of ungulates. The phylogenetic comparative model revealed that capture myopathy (CM), as a proxy for reaction to humans, negatively and significantly influenced the domestication process. The present paper also explored the evolution of CM in equine species in response to the presence of large carnivoran predators during the Pleistocene. Ecologies that preserved most of the large carnivoran predators of equine species also featured more equine taxa with CM (e.g., zebras), which were thus less suitable for domestication.

10.
Animals (Basel) ; 14(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39199892

RESUMO

Success in large carnivore conservation often hinges on local residents' tolerance towards those species. Feelings of powerlessness and frustration with wildlife policies can lead to intolerance of the species. In extreme cases, intolerance may manifest in poaching. Thus, changes in policy may influence the tolerance of wildlife. To examine the connections between policy and tolerance, we examined how policy scenarios influenced anticipated changes in tolerance to wolves Canis lupus. We administered a survey in 2015-2016 in the core wolf range within northern Wisconsin, USA. Using hierarchical cluster analysis, we clustered respondents into groups based on their current tolerance of wolves. We evaluated the behavioral intentions of the clusters and examined the influence of policy scenarios on respondents' anticipated changes in tolerance. Finally, using an information-theoretic model selection framework, we assessed the effects of tolerance clusters and demographic factors. The respondents were clustered into three clusters relative to their current tolerance towards wolves: positive, ambivalent, and negative. Each cluster exhibited significantly different behavioral intentions and anticipated changes in tolerance for all scenarios. In all scenarios, respondents who already held positive attitudes towards wolves were significantly less likely to report expected changes in tolerance toward wolves following changes in wolf management. However, respondents who held ambivalent or negative attitudes towards wolves were significantly more likely to report expected changes in tolerance towards wolves following changes in wolf management. Regarding a regulated wolf hunting and trapping season, we observed a Simpson's Paradox, wherein, when examined in aggregate, no clear pattern emerged, but when examined at the cluster level, important and intuitive patterns emerged. Our demographic model results suggest that policy changes resulting in greater state management authority over wolves, especially authority to implement certain forms of legal killing of wolves, could result in significant increases in tolerance for individuals who identify as hunters, have lost livestock to a predator, or are currently ambivalent or negative towards wolves. Our work elucidates the nuanced relationship between tolerance of wildlife and wildlife policy and identifies a potential ecological fallacy.

11.
Ecol Evol ; 14(8): e70204, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39170053

RESUMO

The ongoing expansion of wolf (Canis lupus) populations in Europe has led to a growing demand for up-to-date abundance estimates. Non-invasive genetic sampling (NGS) is now widely used to monitor wolves, as it allows individual identification and abundance estimation without physically capturing individuals. However, NGS is resource-intensive, partly due to the elusive behaviour and wide distribution of wolves, as well as the cost of DNA analyses. Optimisation of sampling strategies is therefore a requirement for the long-term sustainability of wolf monitoring programs. Using data from the 2020-2021 Italian Alpine wolf monitoring, we investigate how (i) reducing the number of samples genotyped, (ii) reducing the number of transects, and (iii) reducing the number of repetitions of each search transect impacted spatial capture-recapture population size estimates. Our study revealed that a 25% reduction in the number of transects or, alternatively, a 50% reduction in the maximum number of repetitions yielded abundance estimates comparable to those obtained using the entire dataset. These modifications would result in a 2046 km reduction in total transect length and 19,628 km reduction in total distance searched. Further reducing the number of transects resulted in up to 15% lower and up to 17% less precise abundance estimates. Reducing only the number of genotyped samples led to higher (5%) and less precise (20%) abundance estimates. Randomly subsampling genotyped samples reduced the number of detections per individual, whereas subsampling search transects resulted in a less pronounced decrease in both the total number of detections and individuals detected. Our work shows how it is possible to optimise wolf monitoring by reducing search effort while maintaining the quality of abundance estimates, by adopting a modelling framework that uses a first survey dataset. We further provide general guidelines on how to optimise sampling effort when using spatial capture-recapture in large-scale monitoring programmes.

12.
Acta Parasitol ; 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39212903

RESUMO

PURPOSE: At least thirty species of wild carnivores have been recorded harboring Bartonella, and one of the most common pathogenic species infecting them is Bartonella rochalimae, which can cause endocarditis in humans and dogs. This bacterium can infect various mammals including wild carnivores, as well as ectoparasitic vectors such as fleas and ticks. Here we report the presence of B. rochalimae, in a Pulex simulans flea collected from a Mephitis macroura skunk in the municipality of Santa Cruz in Sonora, Mexico. METHODS: Fleas were collected from a M. macroura in Sonora, Mexico, in October 2019. They were identified to species level and subsequently tested for the presence of Bartonella using molecular tools including conventional PCR, sequencing, and phylogenetic analysis. RESULTS: A total of 10 P. simulans fleas (one male, nine females) were collected from the M. macroura skunk. The PCR and phylogenetic analysis indicated a prevalence of 10% (1/10) and a sequence clustered with the clade of B. rochalimae. CONCLUSIONS: We confirmed the presence of B. rochalimae in a P. simulans flea collected from a M. macroura skunk in the area of Santa Cruz, Sonora, Mexico. Based on our results and previous studies in northern Mexico, which are consistent, it is necessary to continue monitoring Bartonella in M. macroura skunks and their fleas, since they could be important reservoirs of this bacterium in northern Mexico.

13.
Sci Rep ; 14(1): 20275, 2024 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-39217220

RESUMO

According to sexual selection theory, the sexes are faced with opposing evolutionary goals. Male fitness benefits from access to females, whereas female fitness is constrained by food resources and safety for themselves and their offspring. Particularly in large solitary carnivores, such as polar bears (Ursus maritimus), these divergent goals can potentially lead to conflict between the sexes. Outside the mating season, when polar bears are on the move across vast distances, the consequences of such conflict can become apparent when individuals arrive at the same food source. To investigate interrelationships between the sexes, we observed successive polar bears visiting a bird breeding colony to feed on clutches of eggs. We found that males succeeded females more frequently and more closely than expected by chance. Moreover, when males were closer to conspecifics, they walked faster, spent less time in the colony and ingested less food. In contrast, female foraging performance was not associated with proximity to other bears. Irrespective of proximity, females generally spent short periods in the colony and ingested fewer clutches than males. Our results suggest that in polar bears, there is a trade-off between the benefits of food intake and the opportunities (in males) and risks (in females) posed by encountering conspecifics.


Assuntos
Estações do Ano , Ursidae , Animais , Ursidae/fisiologia , Feminino , Masculino , Comportamento Sexual Animal/fisiologia , Comportamento Alimentar/fisiologia , Reprodução/fisiologia
14.
J Mammal ; 105(4): 740-751, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39081268

RESUMO

Old-growth forests harbor a large amount of complex structural features that result in a wide array of wildlife habitats. However, intensive forest management is gradually converting old-growth forest into younger, even-aged stands, reducing structural complexity and threatening the persistence of old-growth-dependent species. Maintaining elements of complex stand structure is critical to the conservation of old-growth forest specialists that use different habitat components at different periods of their annual cycle, and it requires a comprehensive understanding of seasonal variation in the habitat needs of these species. However, difficulties in observing free-ranging animals have sometimes limited our ability to assess such variations in habitat requirements, especially for small, elusive species. To address this, we used GPS telemetry collars to describe fine-scale habitat selection patterns of 6 male American Martens (Martes americana) during 2 contrasting periods of the year (snow-free, from mid-April to mid-November; snow-covered, from mid-November to mid-April), an objective formerly hard to achieve using conventional VHF telemetry. We used resource selection functions conducted at the fourth order of selection to compare habitat characteristics found at the sites used by martens (GPS locations, n = 100) to those found on an equal number of available sites (random points, n = 100) within each individual seasonal home range. We conducted vegetation surveys on these 200 sites to describe habitat and built candidate models representing different concurrent hypotheses. Our results showed that proxies of prey availability, predator avoidance, and thermal constraints were the primary factors influencing marten habitat selection during both periods, although their respective importance differed between periods. Martens selected sites with a high density of large-diameter snags (≥30·ha-1), high conifer canopy closure (≥53%), and a dense lateral cover (≥81%) during the snow-free period, but selected sites with a high volume of coarse woody debris (≥64 m3·ha-1) and high conifer canopy closure (≥48%) during the snow-covered period. Our results highlight the importance of contrasting seasonal changes in habitat selection patterns of small carnivores and may help maintain structural attributes in the landscape that are suitable for male American Martens.

15.
Elife ; 122024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38949865

RESUMO

Spatial and temporal associations between sympatric species underpin biotic interactions, structure ecological assemblages, and sustain ecosystem functioning and stability. However, the resilience of interspecific spatiotemporal associations to human activity remains poorly understood, particularly in mountain forests where anthropogenic impacts are often pervasive. Here, we applied context-dependent Joint Species Distribution Models to a systematic camera-trap survey dataset from a global biodiversity hotspot in eastern Himalayas to understand how prominent human activities in mountain forests influence species associations within terrestrial mammal communities. We obtained 10,388 independent detections of 17 focal species (12 carnivores and five ungulates) from 322 stations over 43,163 camera days of effort. We identified a higher incidence of positive associations in habitats with higher levels of human modification (87%) and human presence (83%) compared to those located in habitats with lower human modification (64%) and human presence (65%) levels. We also detected a significant reduction of pairwise encounter time at increasing levels of human disturbance, corresponding to more frequent encounters between pairs of species. Our findings indicate that human activities can push mammals together into more frequent encounters and associations, which likely influences the coexistence and persistence of wildlife, with potential far-ranging ecological consequences.


Assuntos
Biodiversidade , Florestas , Atividades Humanas , Mamíferos , Animais , Humanos , Ecossistema , Análise Espaço-Temporal
16.
PeerJ ; 12: e17693, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39006024

RESUMO

Background: Driven by habitat loss and fragmentation, large carnivores are increasingly navigating human-dominated landscapes, where their activity is restricted and their behaviour altered. This movement, however, raises significant concerns and costs for people living nearby. While intricately linked, studies often isolate human and carnivore impacts, hindering effective management efforts. Hence, in this study, we brought these two into a common framework, focusing on an interface area between the critical tiger habitat and the human-dominated multiple-use buffer area of a central Indian protected area. Methods: We employed a fine-scale camera trap survey complemented by GPS-collar movement data to understand spatio-temporal activity patterns and adjustments of tigers in response to anthropogenic pressures. We used an occupancy framework to evaluate space use, Bayesian circular GLMs to model temporal activity, and home range and step length analyses to assess the movement patterns of tigers. Further, we used predation-risk models to understand conflict patterns as a function of tiger presence and other habitat variables. Results: Despite disturbance, a high proportion of the sampled area was occupied by 17 unique tigers (ψ = 0.76; CI [0.73-0.92]). The distance to villages (ß ± SE = 0.63 ± 0.21) and the relative abundance of large-bodied wild prey (ß ± SE = 0.72 ± 0.37) emerged as key predictors of tiger space use probability, indicating a preference for wild prey by tigers, while human influences constrained their habitat utilisation. Distance to villages was also identified as the most significant predictor of the tigers' temporal activity (µ ± σ = 3.03 ± 0.06 rad) that exhibited higher nocturnality near villages. A total of 11% of tiger home ranges were within village boundaries, accompanied by faster movement in these areas (displacement 40-82% higher). Livestock depredation probability by tigers increased with proximity to villages (P = 0.002) and highway (P = 0.003). Although tiger space use probability (P = 0.056) and wild prey abundance (P = 0.134) were non-significant at the 0.05 threshold, their presence in the best-fit predation-risk model suggests their contextual relevance for understanding conflict risk. The results highlight the importance of appropriately managing livestock near human infrastructures to effectively mitigate conflict. Conclusions: Shared space of carnivores and humans requires dynamic site-specific actions grounded in evidence-based decision-making. This study emphasises the importance of concurrently addressing the intricate interactions between humans and large carnivores, particularly the latter's behavioural adaptations and role in conflict dynamics. Such an integrated approach is essential to unravel cause-effect relationships and promote effective interface management in human-dominated landscapes.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Comportamento Predatório , Tigres , Animais , Tigres/fisiologia , Comportamento Predatório/fisiologia , Humanos , Índia , Teorema de Bayes , Efeitos Antropogênicos
17.
Ecol Evol ; 14(7): e11597, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38988348

RESUMO

Earth's most imperiled and iconic wildlife are facing tough decisions under increasing human pressure and limited resources. Swimming across rivers and water bodies filled with high densities of predators may be one such example. In African lions Panthera leo, previous water crossings (recorded in the peer-reviewed and gray literature, on film, and found using Google Search, and YouTube) have recorded distances ranging from <10 to 100 m, with some resulting in mortality by Nile Crocodiles Crocodylis niloticus. However, we observed a coalition of male lions swimming >1 km across Uganda's Kazinga channel located in the Queen Elizabeth National Park six times, and recorded this behavior on film on February 1st 2024. We speculate that three factors could be driving these lions to take long-distance swims with a high density of crocodiles and hippos Hippopotamus amphibius, namely (1) the lack of lionesses in this ecosystem, (2) intraspecific fights over territory with other male coalitions, and (3) the only other land connection giving lions access to the peninsula is a small road bridge with a strong human presence.

18.
AIMS Neurosci ; 11(2): 63-75, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38988882

RESUMO

Huntington's disease (HD), a rare autosomal dominant neurodegenerative disease, causes the gradual deterioration of neurons in the basal ganglia, specifically in the striatum. HD displays a wide range of symptoms, from motor disturbances such as chorea, dystonia, and bradykinesia to more debilitating symptoms such as cognitive decline, behavioral abnormalities, and psychiatric disturbances. Current research suggests the potential use of dietary interventions as viable strategies for slowing the progression of HD. Most notably, the Mediterranean, vegan, carnivore, paleo, and ketogenic diets have gained attention due to their hypothesized impact on neuroprotection and symptomatic modulation in various neurodegenerative disorders. Despite substantial nutritional differences among these diets, they share a fundamental premise-that dietary factors have an influential impact in modifying pertinent biological pathways linked to neurodegeneration. Understanding the intricate interactions between these dietary regimens and HD pathogenesis could open avenues for personalized interventions tailored to the individual's specific needs and genetic background. Ultimately, elucidating the multifaceted effects of these diets on HD offers a promising framework for developing comprehensive therapeutic approaches that integrate dietary strategies with conventional treatments.

19.
Mov Ecol ; 12(1): 51, 2024 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-39026354

RESUMO

BACKGROUND: Spatial behavior, including home-ranging behaviors, habitat selection, and movement, can be extremely informative in estimating how animals respond to landscape heterogeneity. Responses in these spatial behaviors to features such as human land modification and resources can highlight a species' spatial strategy to maximize fitness and minimize mortality. These strategies can vary on spatial, temporal, and individual scales, and the combination of behaviors on these scales can lead to very different strategies among species. METHODS: Harnessing the variation present at these scales, we characterized how species may respond to stimuli in their environments ranging from broad- to fine-scale spatial responses to human modification in their environment. Using 15 bobcat-years and 31 coyote-years of GPS data from individuals inhabiting a landscape encompassing a range of human land modification, we evaluated the complexity of both species' responses to human modification on the landscape through their home range size, habitat selection, and functional response behaviors, accounting for annual, seasonal, and diel variation. RESULTS: Bobcats and coyotes used different strategies in response to human modification in their home ranges, with bobcats broadly expanding their home range with increases in human modification and displaying temporal consistency in functional response in habitat selection across both season and time of day. Meanwhile, coyotes did not expand their home ranges with increased human modification, but instead demonstrated fine-scale responses to human modification with habitat selection strategies that sometimes varied by time of day and season, paired with functional responses in selection behaviors. CONCLUSIONS: These differences in response to habitat, resources, and human modification between the two species highlighted the variation in spatial behaviors animals can use to exist in anthropogenic environments. Categorizing animal spatial behavior based on these spatiotemporal responses and individual variation can help in predicting how a species will respond to future change based on their current spatial behavior.

20.
Trends Ecol Evol ; 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39068138

RESUMO

Individual behavioral plasticity enables animals to adjust to different scenarios. Yet, personality traits limit this flexibility, leading to consistent interindividual differences in behavior. These individual behavioral traits have the potential to govern community interactions, although testing this is difficult in complex natural systems. For large predators who often exert strong effects on ecosystem functioning, this behavioral diversity may be especially important and lead to individualized ecosystem roles. We present a framework for quantifying individual behavioral plasticity and personality traits of large wild predators, revealing the extent to which certain natural behaviors are governed by these latent traits. The outcomes will reveal how the innate characteristics of wildlife can scale up to affect community interactions.

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