Same place, different time, head up: Multiple antipredator responses to a recolonizing apex predator

Prey adjust their antipredator behavioral tactics to minimize the risk of an encounter with predators.Spatiotemporal responses of prey to pred-ators have been reported,but the nature of antipredator response is not ubiquitous and it is the object of increasing interest,especially consid-ering the recent recovery of large carnivores in Europe,and the potential for behavioral antipredator responses to elicit consequences at the ecosystem level.We have tested multiple antipredator responses by fallow deer Dama dama to wolf Canis lupus in a Mediterranean protected area recently recolonized by this apex predator.Through intensive camera trapping,we tested for temporal and spatial association between predator and prey,and we have also studied deer vigilance in forest habitats where focal observations are usually impossible.Wolf detection rates were spatially associated with those of fallow deer.Accordingly,no evidence was found for fallow deer avoiding sites with higher predator detection rates.Temporal activity patterns were significantly different between the 2 species,with the wolf being mainly nocturnal whereas fallow deer was active especially during daylight.A comparison with a preliminary study strongly suggests an increase in the diurnal activity of fallow deer along with the stabilization of wolf presence in the area.Both the rate and the duration of vigilance of female fallow deer increased with the local frequency of wolf activity.We suggest an antipredator response based on temporalrather than spatialavoidance,as well as increasedvigilance.

Competitor densities,habitat,and weather:effects on interspecific interactions between wild deer species

There is a growing interest on the potential interplay between weather,habitat,and interspecific competition on population dynamics of wild herbivores.Favorable environmental conditions may buffer the negative effects of competition;conversely,competition may be expected to be stronger under harsh environmental conditions.We investigated relationships between competitor abundance,weather,and habitat cover on density and local distribution of a medium-sized herbivore,the roe deer Capreolus capreolus,as well as its spatial overlap with fallow deer Dama dama in a Mediterranean protected area.Over 11 years(2007–2017),roe deer density was not affected by spring–summer rainfall in the previous year and decreased with increasing density of fallow deer in the previous year.Hence,over the considered temporal scale,results supported a major role of competition over weather in influencing population trends of roe deer.At a finer spatial scale,roe deer occupancy was negatively affected by local abundance of fallow deer,especially in“poorer”habitats.We found a slight support for a positive effect of fallow deer density on interspecific spatial overlap.Moreover,fine-scale spatial overlap between deer species increased with decreasing rainfall in spring–summer.Fallow deer were introduced to our study area in historical times and their role as superior competitors over roe deer has been found also in other study areas.We suggest a potential role of harsh weather conditions during the growing season of vegetation(i.e.scarce rainfall)in triggering the potential for ecological overlap,emphasizing the negative effects of interspecific competition.

Joint effects of weather and interspecific competition on foraging behavior and survival of a mountain herbivore

Weather variations have the potential to in fluence species interactions, although effects on competitive interactions between species are poorly known. Both weather and competition can influence foraging behavior and survival of herbivores during nursing/weaning, a critical period in the herbivore life cycle. We evaluated the joint effects of weather and competition with red deer Cervus elaphus on the foraging behavior of adult female Apen nine chamois Rupicapra pyrenaica ornata in summer, and on winter survival of chamois kids. High temperature and low rainfall during the growing seas on of vegetation had negative effects on bite rate. Effects of weather were greater in forb patches, including cold-adapted, nutritious plants of key importanee to chamois, than in graminoid ones. Our results confirm previous indications of a negative effect of competition on bite rate of female chamois and on kid survival. Furthermore, harsh weather conditions and competition with deer had additive, negative roles on foraging behavior and survival of chamois. Growing temperatures are expected to influence distribution, growth, and/or nutritional quality of plants;competition would reduce pasture quality and food availability through resource depletion. Both factors would limit food/energy intake rates during summer, reducing survival of the youngest cohorts in winter. We suggest that interspecific competition can be an important additive factor to the effects of weather changes on behavior and demography.