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In many species, decreasing body size has been associated with increasing temperatures. Although climate-induced phenotypic shifts, and evolutionary impacts, can affect the structure and functioning of marine and terrestrial ecosystems through biological and metabolic rules, evidence for shrinking body size is often challenged by (i) relatively short intervals of observation, (ii) a limited number of individuals, and (iii) confinement to small and isolated populations. To overcome these issues and provide important multi-species, long-term information for conservation managers and scientists, we compiled and analysed 222 961 measurements of eviscerated body weight, 170 729 measurements of hind foot length and 145 980 measurements of lower jaw length, in the four most abundant Alpine ungulate species: ibex (Capra ibex), chamois (Rupicapra rupicapra), red deer (Cervus elaphus) and roe deer (Capreolus capreolus). Regardless of age, sex and phylogeny, the body mass and size of these sympatric animals, from the eastern Swiss Alps, remained stable between 1991 and 2013. Neither global warming nor local hunting influenced the fitness of the wild ungulates studied at a detectable level. However, we cannot rule out possible counteracting effects of enhanced nutritional resources associated with longer and warmer growing seasons, as well as the animals' ability to migrate along extensive elevational gradients in the highly diversified alpine landscape of this study.

Animals move to interact with the environment in order to find food resources and cover. Intrinsic characteristics affecting feeding and antipredatory strategies likely shape variation in movement patterns and home range formation between individuals, populations and species., Browsing herbivores selectively forage on patchily distributed resources in areas with more canopy cover, whereas mixed feeders and grazers feed on more open grasslands and tend to aggregate as an antipredatory strategy. We therefore predicted that at small temporal scales, browsers will show greater net displacements (i.e. typical of searching patterns) than mixed feeders or grazers; but at larger temporal scales, we expect the opposite pattern, since gregarious species will need to use larger areas to feed the whole herd. We also predicted that the feeding/antipredatory strategy will determine the behavioural responses to other environmental factors., To test this, we compared spatial movement patterns at multiple scales (from 20-min intervals to annual home ranges) of three sympatric, similar-sized, alpine ungulates which differ in their feeding/antipredatory strategy: roe deer (solitary browsers), mouflon (gregarious grazers) and chamois (intermediate feeders in smaller groups). We used location data from GPS-collared females of the three species in the French Alps., As predicted, we found that multi-scale spatial patterns depended on the feeding/antipredatory strategy. Browsers foraged within smaller range areas, searching back and forth. Mixed feeders and, especially, grazers covered larger areas, presumably to satisfy herd needs. The feeding/antipredatory strategies also determined the interspecific variability in behavioural responses to factors such as maternal status, weather, habitat type or human disturbance, supporting our hypothesis., Exploring interspecific variability, we showed how movement behaviour and home range formation vary substantially, even among species within the same guild. This mechanism might be important to maintain intra-guild multi-species associations and increase biodiversity, through contributing to niche segregation and, thus, coexistence. [ABSTRACT FROM AUTHOR]

[fr] Au nord du Pakistan, les ongulés alpins se distribuent dans des habitats diversifiés mais leur nombre a diminué ces dernières décades, peut-être du fait du braconnage et de la dégradation de l'habitat par les troupeaux domestiques. Si Von veut mettre en place une gestion soutenable des Caprinae sauvages, l'expérience montre qu'une solution pragmatique est l'établissement d'un programme de chasse au trophée géré par la population locale. Ainsi, depuis les années 1990 s'est développé dans la vallée Bar un projet de conservation de la population de bouquetins basé sur des trophés de chasse à prix élevés pouvant générer des revenus pour le développement local. En 2000, une révision a été faite pour connaître les effets de ce programme sur le bouquetin et ses bénéfices pour les habitants de la zone. La densité et les index de productivité ont été déterminés année par année. L'effectivité du projet et son influence sur les revenus locaux ont aussi été étudiés pour obtenir h la fois une vision historique et actuelle. Cette enquête a été répétée dans la vallée voisine de Naltar, où aucun projet semblable ne s'est établi. La population de bouquetin de la vallée Bar s'est relativement stabilisée cette dernière décade, tandis que celle de Nalthar et d'autres vallées a presque disparu. [es] Aunque los ungidados alpinos son ubicuos en el norte de Pakistán, han disminuido en número en las últimas décadas, probablemente debido al furtivismo y la degradación del hábitat producida por el ganado. La experiencia indica que la forma más pragmática de desarrollar una gestión sostenible de los caprinos silvestres es a través de un plan de caza de trofeo con participación local. Desde principio de los 90 en el valle de Bar se ha llevado a cabo un proyecto basado en la caza de trofeo de alta cotización, obteniendo así fondos para el desarrollo local. En 2000 se realizó una auditoría con el fin de determinar el efecto del proyecto en el íbice y sus beneficios para la población local. Los datos obtenidos con el seguimiento del íbice fueron analizados retrospectivamente para determinar los índices de productividad y densidad por años. Se encuesto a las familias del valle de Bar con el fin de averiguar su percepción histórica y actual sobre el funcionamiento y efectividad del proyecto. Se repitió la encuesta en el valle adyacente de Naltar, donde no existe un proyecto similar. En el valle de Bar la población de íbice permaneció relativamente estable durante la pasada década, mientras que en el valle de Naltar, y en otros valles, casi ha desaparecido.

Direct effects of climate change on animal physiology, and indirect impacts from disruption of seasonal synchrony and breakdown of trophic interactions are particularly severe in Arctic and Alpine ecosystems. Unravelling biotic from abiotic drivers, however, remains challenging because high-resolution animal population data are often limited in space and time. Here, we show that variation in annual horn growth (an indirect proxy for individual performance) of 8043 male Alpine ibex ( Capra ibex) over the past four decades is well synchronised among eight disjunct colonies in the eastern Swiss Alps. Elevated March to May temperatures, causing premature melting of Alpine snowcover, earlier plant phenology and subsequent improvement of ibex food resources, fuelled annual horn growth. These results reveal dependency of local trophic interactions on large-scale climate dynamics, and provide evidence that declining herbivore performance is not a universal response to global warming even for high-altitude populations that are also harvested. [ABSTRACT FROM AUTHOR]

Past analysis has shown that the population dynamics of Alpine ibex Capra ibex ibex are regulated by both population density and winter snow accumulation. However, recent time series of the ibex counts in the Gran Paradiso National Park, Italy, show interesting trends in comparison with historical snow data: while the winter snow depth has steadily decreased since the beginning of the 1980s, the ibex population experienced rapid growth during the 1980s and the early 1990s, followed by a strong decrease. To explain these dynamics, we built novel age-structured population models in which demographic parameters depended on density and snow depth. They included a non-monotonic effect of snow depth and density on the vital rates, the age and sex structure of the population, and spatial segregation between females and males. Using information criteria (AICc, BIC and SRM), we selected the best models and found that: 1) snow and density interacted in determining the demography of all population sex and age classes, thus confirming that unfavourable climatic conditions intensified the density dependence of the population, 2) the effect of snow was non-monotonic on weaning success and rate of demographic variation of kids, which were maximal for intermediate snow depths, and 3) accounting for spatial segregation between sexes improved the fitting of the models, which suggests that the different use of space made by males and females influenced intraspecific competition. When the selected models were recalibrated using past data and used to simulate recent trends, they underestimated both the rapid growth of the 1980s-1990s and the recent decline of the population.Using the novel sex- and age-structuredmodels,we found that the underestimation of the peak was mainly due to deficiencies of adult demography models, while the overestimation of the recent population abundance was caused by shortcomings in the models of recruitment. [ABSTRACT FROM AUTHOR]