Stoat monitoring in the Rhône Valley: Survey of the utilisation of stone piles by stoats and small mammals

As part of measures to increase biodiversity and create ecological networks, stone piles have been installed throughout the Rhône Valley. These structures were intended to act as refuges and breeding sites for a variety of species, in particular stoats. To assess the impact of these structures on biodiversity, a large number of stone piles were monitored with specially designed camera traps between August and November 2023. The main focus of this study was to document the spatio-temporal use of these structures by both stoats and other micromammals.

The main conclusions are that stoats in the Rhône Valley are rather secretive, but seem to be widespread. Previous observations of the species have been concentrated in an area between Martigny and Sion. While our study confirms this finding, observations in the Sierre area suggest that the distribution is wider than previously known. Stoat activity was highest in the morning hours until midday and lowest at night. Stone piles were attractive to a variety of small insectivorous (shrews) and carnivorous (stoats) species, which provide important ecosystem services (e.g. pest control) in intensively managed orchards.