Co-Adaptation Is Key to Coexisting with Large Carnivores

There is a pressing need to integrate large carnivore species into multi-use landscapes outside protected areas. However, an unclear understanding of coexistence hinders the realization of this goal. Here, we provide a comprehensive conceptualization of coexistence in which mutual adaptations by both large carnivores and humans have a central role

Dietary and Reproductive Responses of Arctic Foxes to Changes in Small Rodent Abundance

Between 1988 and 1995, dens in three adjacent arctic fox (Alopex lagopus) territories were monitored in an alpine environment in south-central Norway (the Snøhetta plateau). A total of 675 scats were collected at dens in both winter and summer, and the numbers of resident adults and pups at emergence were counted each summer. Small rodents (mainly Lemmus sp. and Microtus sp.) were the most frequently consumed prey and made up the greatest volume within scats, in all seasons and at all stages of the rodent cycle. Small rodents were followed in frequency by reindeer (Rangifer tarandus), hares (Lepus timidus), birds, and vegetation. Birds and vegetation were more common in the summer diet than in the winter diet, reflecting their seasonal availability. The relative volume of reindeer and birds in the diet decreased with increasing rodent abundance. Increased pup production was associated with years of high rodent abundance and a high occurrence of rodents in the diet. Adult numbers were not associated with rodent abundance.Entre 1988 et 1995, on a observé les terriers du renard arctique (Alopex lagopus), dans trois territoires contigus situés dans un environnement alpin du centre-sud de la Norvège (le plateau Snøhetta). En hiver et en été, on a recueilli un total de 675 excréments sur le site des terriers, et chaque été, on a compté le nombre de résidents adultes et de petits qui faisaient leur première sortie du terrier. Les petits rongeurs (surtout Lemmus sp. et Microtus sp.) étaient la proie la plus fréquemment consommée et constituaient le plus gros volume des excréments, en toute saison et à toute étape de la vie du rongeur. Les petits rongeurs étaient suivis en fréquence par le renne (Rangifer tarandus), le lièvre (Lepus timidus), les oiseaux et la végétation. Les oiseaux et les plantes étaient plus courants dans le régime alimentaire estival que dans celui hivernal, ce qui reflétait la disponibilité saisonnière. Le volume relatif de renne et d'oiseaux dans l'alimentation diminuait avec l'augmentation de rongeurs. La production accrue de petits était associée aux années de grande abondance de rongeurs et à une occurrence élevée de rongeurs dans l'alimentation. Le nombre des adultes n'était pas relié à l'abondance de rongeurs

Activity patterns of eurasian lynx are modulated by light regime and individual traits over a wide latitudinal range

The activity patterns of most terrestrial animals are regarded as being primarily influenced by light, although other factors, such as sexual cycle and climatic conditions, can modify the underlying patterns. However, most activity studies have been limited to a single study area, which in turn limit the variability of light conditions and other factors. Here we considered a range of variables that might potentially influence the activity of a large carnivore, the Eurasian lynx, in a network of studies conducted with identical methodology in different areas spanning latitudes from 49 degrees 7'N in central Europe to 70 degrees 00'N in northern Scandinavia. The variables considered both light conditions, ranging from a day with a complete day-night cycle to polar night and polar day, as well as individual traits of the animals. We analysed activity data of 38 individual free-ranging lynx equipped with GPS-collars with acceleration sensors, covering more than 11,000 lynx days. Mixed linear additive models revealed that the lynx activity level was not influenced by the daily daylight duration and the activity pattern was bimodal, even during polar night and polar day. The duration of the active phase of the activity cycle varied with the widening and narrowing of the photoperiod. Activity varied significantly with moonlight. Among adults, males were more active than females, and subadult lynx were more active than adults. In polar regions, the amplitude of the lynx daily activity pattern was low, likely as a result of the polycyclic activity pattern of their main prey, reindeer. At lower latitudes, the basic lynx activity pattern peaked during twilight, corresponding to the crepuscular activity pattern of the main prey, roe deer. Our results indicated that the basic activity of lynx is independent of light conditions, but is modified by both individual traits and the activity pattern of the locally most important prey

Institutional stakeholders’ views on jaguar conservation issues in central Brazil

AbstractLarge carnivore management is typically a source of heated controversy worldwide and, in the Americas, jaguars (Panthera onca) are at the centre of many human–wildlife conflicts. Although findings suggest that social, rather than economic, factors are important reasons for why humans kill jaguars, few studies focus on stakeholder attitudes towards jaguar conservation beyond quantifying livestock depredation. Yet insights from other large carnivore conflicts demonstrate the importance of the political landscape and stakeholder attitudes in carnivore conservation. To explore the extent to which stakeholder views about jaguar conservation aligned with institutional arrangements, we conducted a stakeholder analysis among personnel working for key institutions in central Brazil. Using Q methodology, we identified three stakeholder perspectives focusing on: A) jaguars’ intrinsic right to exist; B) wider ecocentric values; and C) contesting jaguar-focused conservation. The three institutional stakeholder groups all accepted the jaguar’s fundamental right to exist and agreed that it was important to establish protected areas for jaguars. Yet, institutional stakeholder views diverged regarding the desired distribution of jaguars in Brazil, hunting policies, and the effects of hunting and development projects on jaguar conservation. These differences and their underlying motivations are important to consider for successful jaguar conservation strategies in Brazil

Predation or scavenging? Prey body condition influences decision-making in a facultative predator, the wolverine

The interaction between predators and their prey is a key factor driving population dynamics and shaping wildlife communities. Most predators will scavenge in addition to killing their own prey, which alters predation effects and implies that one cannot treat these as independent processes. However, the relative importance of predation vs. scavenging and the mechanisms driving variation of such are relatively unstudied in ecological research on predator-prey relationships. Foraging decisions in facultative predators are likely to respond to environmental conditions (e.g., seasonality) and inter- or intraspecific interactions (e.g., prey availability, presence of top predators, scavenging competition). Using data on 41 GPS-collared wolverines (Gulo gulo) during 2401 monitoring days, in four study sites in Scandinavia, we studied variation in diet and feeding strategies (predation vs. scavenging), along a gradient of environmental productivity, seasonality, density, and body mass of their main prey, semidomestic reindeer (Rangifer tarandus). The most important factor affecting the relative extent of predation and scavenging was mean prey body mass. Predation was more pronounced in summer, when vulnerable reindeer calves are abundant, and individual kill rates were negatively related to local reindeer body mass. This relationship was absent in winter. The probability of scavenging was higher in winter and increased with decreasing local reindeer body mass, likely as a response to increased carrion supply. Wolverine feeding strategy was further influenced by predictable anthropogenic food resources (e.g., slaughter remains from hunted ungulates) and the presence of a top predator, Eurasian lynx (Lynx lynx), which provided a continuous carrion supply promoting scavenging. Our results suggest that wolverine feeding strategies are flexible and strongly influenced by seasonally dependent responses to prey body condition in combination with carrion supply. This study demonstrates that large-scale environmental variation can result in contrasting predator feeding strategies, strongly affecting trophic interactions and potentially shaping the dynamics of ecological communities

Decomposing risk: landscape structure and wolf behavior generate different predation patterns in two sympatric ungulates

Recolonizing carnivores can have a large impact on the status of wild ungulates, which have often modified their behavior in the absence of predation. Therefore, understanding the dynamics of reestablished predator–prey systems is crucial to predict their potential ecosystem effects. We decomposed the spatial structure of predation by recolonizing wolves (Canis lupus) on two sympatric ungulates, moose (Alces alces) and roe deer (Capreolus capreolus), in Scandinavia during a 10-year study. We monitored 18 wolves with GPS collars, distributed over 12 territories, and collected records from predation events. By using conditional logistic regression, we assessed the contributions of three main factors, the utilization patterns of each wolf territory, the spatial distribution of both prey species, and fine-scale landscape structure, in determining the spatial structure of moose and roe deer predation risk. The reestablished predator–prey system showed a remarkable spatial variation in kill occurrence at the intra-territorial level, with kill probabilities varying by several orders of magnitude inside the same territory. Variation in predation risk was evident also when a spatially homogeneous probability for a wolf to encounter a prey was simulated. Even inside the same territory, with the same landscape structure, and when exposed to predation by the same wolves, the two prey species experienced an opposite spatial distribution of predation risk. In particular, increased predation risk for moose was associated with open areas, especially clearcuts and young forest stands, whereas risk was lowered for roe deer in the same habitat types. Thus, fine-scale landscape structure can generate contrasting predation risk patterns in sympatric ungulates, so that they can experience large differences in the spatial distribution of risk and refuge areas when exposed to predation by a recolonizing predator. Territories with an earlier recolonization were not associated with a lower hunting success for wolves. Such constant efficiency in wolf predation during the recolonization process is in line with previous findings about the naı¨ve nature of Scandinavian moose to wolf predation. This, together with the human-dominated nature of the Scandinavian ecosystem, seems to limit the possibility for wolves to have large ecosystem effects and to establish a behaviorally mediated trophic cascade in Scandinavia

Movement and activity pattern of a collared tigress in a human-dominated landscape in central India

Tigers (Panthera tigris) are wide-ranging species, and a permeable landscape matrix outside Protected Areas (PAs) is extremely important for their dispersal. A tigress which had fallen in a water duct in the Nagpur district was rescued by the Forest Department on 12th October, 2011 and released on 27th November, 2011 in a forest adjacent to the site of capture. A GPS-GSM collar that we fitted on her indicated that she remained in the same forest area until 25th December, 2011, and then moved eastwards into a human-dominated landscape where she was present until 25th March, 2012, after which the GPS battery ceased to function. She moved a minimum distance of 454.65 km from the time of her release up to 25th March, 2012, using a total area of 726 km² (95% MCP), but between 30th December, 2011 and 25th March, 2012, after moving into the human-dominated forest-agricultural landscape her home range was 431 km² (95% MCP). Her home range also encompassed villages, roads and croplands. Her activity was largely nocturnal and she rested in dense foliage inside forest patches during the day. About half of all the prey items that we identified during this period (n = 12) were wild pigs (Sus scrofa). Although, she was present very close to areas where humans were active in the day, no untoward incident occurred. She was photographed in April 2013, a year after the collar stopped functioning, in the same region about 40 km from the release site, indicating that she is still present in the human-dominated area. Very little is known about tiger ecology, and their temporal and spatial patterns of movement, outside PAs. These areas will be crucial in terms of dispersal between PAs as well as sensitive in terms of conflict

Can we save large carnivores without losing large carnivore science?

Large carnivores are depicted to shape entire ecosystems through top-down processes. Studies describing these processes are often used to support interventionist wildlife management practices, including carnivore reintroduction or lethal control programs. Unfortunately, there is an increasing tendency to ignore, disregard or devalue fundamental principles of the scientific method when communicating the reliability of current evidence for the ecological roles that large carnivores may play, eroding public confidence in large carnivore science and scientists. Here, we discuss six interrelated issues that currently undermine the reliability of the available literature on the ecological roles of large carnivores: (1) the overall paucity of available data, (2) reliability of carnivore population sampling techniques, (3) general disregard for alternative hypotheses to top-down forcing, (4) lack of applied science studies, (5) frequent use of logical fallacies, and (6) generalisation of results from relatively pristine systems to those substantially altered by humans. We first describe how widespread these issues are, and given this, show, for example, that evidence for the roles of wolves (Canis lupus) and dingoes (Canis lupus dingo) in initiating trophic cascades is not as strong as is often claimed. Managers and policy makers should exercise caution when relying on this literature to inform wildlife management decisions. We emphasise the value of manipulative experiments, and discuss the role of scientific knowledge in the decision-making process. We hope that the issues we raise here prompt deeper consideration of actual evidence, leading towards an improvement in both the rigour and communication of large carnivore science

Archiving primary data: solutions for long-term studies

The recent trend for journals to require open access to primary data included in publications has been embraced by many biologists, but has caused apprehension amongst researchers engaged in long-term ecological and evolutionary studies. A worldwide survey of 73 principal investigators (Pls) with long-term studies revealed positive attitudes towards sharing data with the agreement or involvement of the PI, and 93% of PIs have historically shared data. Only 8% were in favor of uncontrolled, open access to primary data while 63% expressed serious concern. We present here their viewpoint on an issue that can have non-trivial scientific consequences. We discuss potential costs of public data archiving and provide possible solutions to meet the needs of journals and researchers

Body size and digestive system shape resource selection by ungulates : a cross-taxa test of the forage maturation hypothesis

The forage maturation hypothesis (FMH) states that energy intake for ungulates is maximised when forage biomass is at intermediate levels. Nevertheless, metabolic allometry and different digestive systems suggest that resource selection should vary across ungulate species. By combining GPS relocations with remotely sensed data on forage characteristics and surface water, we quantified the effect of body size and digestive system in determining movements of 30 populations of hindgut fermenters (equids) and ruminants across biomes. Selection for intermediate forage biomass was negatively related to body size, regardless of digestive system. Selection for proximity to surface water was stronger for equids relative to ruminants, regardless of body size. To be more generalisable, we suggest that the FMH explicitly incorporate contingencies in body size and digestive system, with small-bodied ruminants selecting more strongly for potential energy intake, and hindgut fermenters selecting more strongly for surface water.DATA AVAILABILITY STATEMENT : The dataset used in our analyses is available via Dryad repository (https://doi.org/10.5061/dryad.jsxksn09f) following a year-long embargo from publication of the manuscript. The coordinates associated with mountain zebra data are not provided in an effort to protect critically endangered black rhino (Diceros bicornis) locations. Interested researchers can contact the data owner (Minnesota Zoo) directly for inquiries.https://wileyonlinelibrary.com/journal/elehj2022Mammal Research InstituteZoology and Entomolog