Habitat use of an endangered beetle Carabus hungaricus assessed via radio telemetry

Keywords: ground beetles, insect movement, radio-tracking, tall-grass steppe, temperature

Abstract

Carabus hungaricus is an endangered habitat specialist of tall-grass steppe occurring in Pannonian region. In this study, we used radio telemetry to examine whether habitat type (different habitat patches in steppe mosaic), sex, daytime, temperature and air pressure affect movement activity of the species. For seven-day tracking during the reproductive period of C. hungaricus in October 2017, we used 10 individuals, five males and five females, equipped by 0.3 g VHF transmitters. We found that the average speed was 1.29 m/h for the fastest individual and 0.21 m/h for the slowest one. Considering the shape of trajectories, beetles mostly randomly walked around; only in few cases they covered larger distances between two tracking sessions. Habitat type significantly affected beetles’ movement; the average speed was higher in grassy patches and under common juniper stands, while it decreased in mosses and litter under bushes. Although there was no effect of sex, daytime and air pressure on beetles’ activity the temperature had a positive effect on movement behaviour. We showed that preferred habitat observed from the human perspective was not in fact equally utilized by C. hungaricus. The availability of suitable patches within steppe mosaic can be therefore crucial for species persistence.

Published
2019-11-22