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Traditional agro‐pastoral practices are more beneficial for biodiversity than intensified agricultural systems. Promotion of the growth of natural herbaceous vegetation in pastoral fields can enhance rodent populations and consequently influence ecological aspects of carnivores with rodent‐based diets, like prey consumption in the European wildcat (Felis silvestris). In this article, we investigated the effects of pastoral field extent, season and prey abundance on wildcat consumption of several prey species in the Cantabrian Mountains (NW Spain). Prey consumption in areas with presence of pastoral fields (even in low proportions) was dominated by profitable field‐dwelling rodent species such as Arvicola monticola. Consumption of Arvicola was not correlated with its abundance and was higher during summer and autumn. Apodemus dominated the wildcat diet in areas with higher forest proportion and far from pastoral fields, particularly during spring. Our results suggest that varying habitat use and seasonal changes in prey accessibility may determine wildcat prey consumption in pastoral landscapes. Our results can contribute to highlight the potential benefits of traditional and sustainable pastoral activities for the conservation of the European wildcat across its distribution range. [ABSTRACT FROM AUTHOR]

Roads are human infrastructure that heavily affect wildlife, often with marked impacts on carnivores, including brown bears Ursus arctos. Here, we assessed the potential impact of road networks on the distribution of brown bears in the small, isolated and endangered Cantabrian population of north‐western Spain. To ascertain whether local road networks affect brown bear spatial distribution, we first assessed potential influences on the distance of bear locations to roads using candidate models which included topographic variables, landcover types, bear age and reproductive status, traffic volume and road visibility. Then, we built two sets of habitat suitability models, both with and without roads, to discern the possible loss of habitat suitability caused by roads. The mean distance of bear locations to the nearest road was 968 ± 804 m and the closest road was a low traffic road in 72.5% of cases. Candidate models showed little influence of our variables on bear distance to the nearest road, with the exception of elevation. Habitat suitability models revealed that road networks in our study area seem to have almost no effect on brown bear habitat suitability, except for females with yearlings during the denning season. However, this result may also be a consequence of the fact that only a small proportion (16.5%) of the cells classified as suitable bear habitats were crossed by roads, that is, most of the roads are primarily located in unsuitable bear habitats in the Cantabrian Mountains. Compared to previous studies conducted in other populations, mainly North American ones, our findings might suggest a different response of Eurasian brown bears to roads due to a longer bear‐human coexistence in Europe versus North America. However, the indirect approach used in our study does not exclude other detrimental effects, for example, road mortality, increased stress and movement pattern disruption, only detectable by more direct approaches such as telemetry. [ABSTRACT FROM AUTHOR]

The intricate interplay between predators and prey has long fascinated ecologists, with bats and their diverse prey offering insight into co-evolutionary dynamics. While bats have evolved sophisticated strategies for prey capture, they also face predation pressure. Among their predators, spiders stand out for their diversity of predatory tactics, ranging from hunting assaults and web ensnarement to the deployment of venom. Yet, bat predation records by spiders are mostly from tropical regions, and cases remain notably scarce in temperate regions. Here, we report four new incidences of bat predation and mortality by spiders and their webs in Europe. Our observations include detailed photograph and video documentation of the first record of a spider capturing and consuming a bat pup in Spain, as well as accounts of bats entangled in spider webs on a building and inside bat boxes in the United Kingdom. These findings shed light on understudied predator-prey dynamics, offering valuable insights into spider predation on bats in European ecosystems. Our study emphasises the importance of continued research to improve our understanding of ecological interactions between these elusive and primarily nocturnal taxa., Competing Interests: The authors declare that they have no competing interests., (© 2024 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.)

Intraspecific communication in mammals is well-documented but generally restricted to chemical and acoustic signaling. However, other overlooked channels, such as visual signaling, may be used to communicate among conspecifics. Here, by using experimental manipulations together with camera traps on 13 brown bear ( Ursus arctos ) rubbing trees in the Cantabrian Mountains (northwestern Spain), we document detailed temporal patterns and behavioral aspects of a recently discovered novel communication channel for this species, visual signaling through the trunk debarking of focal trees. Video footage showed that visual marking is a sex-, age-, and time-specific means of communication in brown bears, being performed exclusively by adult males during the mating season (mainly April-June in the study area). Trunk debarking was always associated with chemical marking and was never an isolated behavior, suggesting that visual and chemical signals might be complementary. Visual and chemical marks may provide different information; for example, visual marks could be an indicator of individual size and, thus, the dominance status of adult males looking for mating opportunities. This is the first time that evidence is provided showing that visual signaling in a large carnivore is exclusive to a specific class of individuals (adult males) and linked to reproductive needs only. Bear visual signaling not only represents an advance in our comprehension of animal communication but may also serve to easily locate the mating areas of mammals, which are crucial for large carnivore species, such as the brown bear, that frequently need specific and urgent plans for conservation and management., Competing Interests: None declared., (© The Author(s) 2023. Published by Oxford University Press on behalf of the American Society of Mammalogists.)

The rather limited human ability to understand animal vision and visual signalling has frequently clouded our expectations concerning the visual abilities of other animals. But there are multiple reasons to suspect that visual signalling is more widely employed by animals than previously thought. Because visibility of visual marks depends on the background in which they are seen, species spending most of their time living in dark conditions (e.g., in forests and/or having crepuscular and nocturnal habits) may rely on bright signals to enhance visual display. Here, as a result of experimental manipulations, we present, for the first time ever, evidence supporting the use of a new channel of intraspecific communication by a mammal species, i.e., brown bear Ursus arctos adult males relying on visual marks during mating. Bear reactions to our manipulation suggest that visual signalling could represent a widely overlooked mechanism in mammal communication, which may be more broadly employed than was previously thought.

Scent-mediated communication is considered the principal communication channel in many mammal species. Compared with visual and vocal communication, odors persist for a longer time, enabling individuals to interact without being in the same place at the same time. The brown bear ( Ursus arctos ), like other mammals, carries out chemical communication, for example, by means of scents deposited on marking (or rub) trees. In this study, we assessed rub tree selectivity of the brown bear in the predominantly deciduous forests of the Cantabrian Mountains (NW Spain). We first compared the characteristics of 101 brown bear rub trees with 263 control trees. We then analyzed the potential factors affecting the density of rub trees along 35 survey routes along footpaths. We hypothesized that: (1) bears would select particular trees, or tree species, with characteristics that make them more conspicuous; and (2) that bears would select trees located in areas with the highest presence of conspecifics, depending on the population density or the position of the trees within the species' range. We used linear models and generalized additive models to test these hypotheses. Our results showed that brown bears generally selected more conspicuous trees with a preference for birches ( Betula spp.). This choice may facilitate the marking and/or detection of chemical signals and, therefore, the effectiveness of intraspecific communication. Conversely, the abundance of rub trees along footpaths did not seem to depend on the density of bear observations or their relative position within the population center or its border. Our results suggest that Cantabrian brown bears select trees based on their individual characteristics and their location, with no influence of characteristics of the bear population itself. Our findings can be used to locate target trees that could help in population monitoring., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society of Mammalogists.)