Climate, competition and weather conditions drive vertical displacement and habitat use of an alpine ungulate in a highly topographic landscape

Abstract

Context: Many species experience ecosystem changes due to alterations in climate or interspecific interactions. Animals’ optimal use of landscapes involves adjusting spatial displacement and habitat use according to weather or climate, however, competitive interactions may affect such behavioural responses. Species in alpine landscapes are already at their upper altitudinal range, which can limit behavioural response to ecosystem changes. Objectives: We investigated how ibex’s use of habitat and altitude was affected by weather, climate, and intra- and interspecific competition in an alpine landscape in Switzerland. Methods: We combined data from GPS-collared ibex with data on temperature and precipitation, habitat and altitude, and abundance estimates of ibex, chamois, and red deer within the study area. We modelled how the temporal dynamics of habitat and altitude use by ibex was modified by weather, ungulate abundance, and their interactions. Results: Short- and long-term weather conditions affected ibex’s use of landscape throughout the year as expected based on its ecology, with particularly strong effects of temperature during spring and summer. During spring and autumn, ibex used higher altitudes and less grassland when red deer abundance was high and ibex abundance low. The influence of weather and climate on how ibex used the landscape was only weakly affected by interspecific competition. Conclusions: Our results suggest that the way that ibex use the landscape is affected by environmental conditions and intra- and interspecific interactions. These factors seem to have additive effects on ibex behaviour.