Radio-Tracking Suggests High Dispersal Ability of the Great Capricorn Beetle (Cerambyx cerdo)

Abstract

Dispersal ability is among the key factors affecting the survival of species in today’s fragmented landscapes. One of the most straightforward methods to provide direct measures of animal dispersal is telemetry. Despite its merits, this method has rarely been used for saproxylic beetles. In this study, we examined dispersal ability of the Great Capricorn beetle Cerambyx cerdo (Coleoptera: Cerambycidae), an endangered veteran oak specialist. Using a radio-tracking approach, we tracked 26 individuals (15 males and 11 females) equipped with transmitters for 4 to 17 days (median 14). We observed no disturbance of movements or flight problems due to the transmitter. The daily probability of movement by an individual was 64% and the longest displacement in one day was 1498 m for males and 1080 m for females. For 15% of all individuals, the tracking distance covered was >2200 m. Our results indicate that C. cerdo individuals often move among trees over an area of several kilometres. Such findings contrast with previous results based on a mark-recapture study. The relatively high mobility of the species should be reflected in strategies aiming at its conservation.