A central challenge in animal conservation is to understand how a population may respond to different habitat characteristics, which may affect their growth and viability. At the beginning of the 20 th century, the Cantabrian brown bear Ursus arctos population (north-western Spain) was separated into western and eastern subpopulations. Today, brown bears in the Cantabrian Mountains are recovering and the two subpopulations are reconnected. However, the western portion of the population represents ca. 90% of the entire population, the number of females with cubs-of-the-year has also shown a more rapid increase in the western subpopulation than in the eastern one and mean litter size is significantly larger in the west. By comparing the characteristics of the landscape used by brown bears in the western vs. eastern sectors of the population, we intended highlighting focal elements of landscape composition and structure that may help explain the differences in numbers and fecundity of these two subpopulations. We suggest that habitat use alone might not have the expected role in potentially explaining differences between subpopulations. Both the current positive trend of the Cantabrian population and our results seems to show that the dynamics affecting these subpopulations might be more complex than previously believed and cannot be understood on the basis of habitat analyses only. Suspicions may arise around direct human influences (e.g. persistence of poaching and/or bad practices during hunting) on the different trends exhibited by the two sectors of this endangered bear population.
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.
Artificial food supplementation of wildlife is an increasing practice for species conservation, as well as for hunting and viewing tourism. Yet, our understanding of the implications of wildlife supplementary feeding is still very limited. Concerns have been raised over the potential negative impact of artificial feeding, but the effects of this practice on animal movements and rhythms of activity are just beginning to be investigated. Here, with the aim of studying whether the artificial feeding of brown bears may affect their behaviour, we analysed (1) the probability and intensity of feeding site use at different temporal scales, (2) how the use of artificial feeding sites is related to the bear's age and sex, main periods of the bear's annual cycle (i.e. mating and hyperphagia) and characteristics of the feeding sites, and (3) how the use of artificial feeding may be affecting bear movement patterns. We analysed the movements of 71 radio-collared brown bears in southern-central Finland and western Russian Karelia. Artificial feeding sites had several effects on brown bears in boreal habitats. The probability of a feeding site being used was positively correlated to the stability of this food resource over time, whereas sexes and bear classes (subadults, adults and females with cubs) did not show significant differences in the use of feeding sites, which were visited predominantly at night and slightly more during hyperphagia. The probability of using an artificial feeding site affected the daily net distance only (bears using feeding sites: 3.5 ± 4.5 km, range: 0-29 km; bears not using feeding sites: 4.4 ± 4.9 km, range: 0-47 km). Those brown bears using artificial feeding more intensively moved shorter distances at a lower speed within smaller home ranges compared to bears that used this food sources less. Highly predictable and continuously available anthropogenic food may therefore have substantial impacts on brown bear movement patterns, ecology and health. The recorded changes in movement patterns support the evidence that artificial feeding may have important implications for bear ecology and conservation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.