Mobility and Spatial use of the Ground Beetle species Elaphrus cupreus and Elaphrus uliginosus (Coleoptera: Carabidae)

摘要

Mobility, movements and home-range of Elaphrus cupreus Duftschmidt 1812, a frequent spe-cies, and E uliginosus (Fabricius 1792), one of the most endangered carabids in Europe, were studied in northern Germany in five grassland sites and one alder wood site. It was supposed that lower mobility could be one reason for the higher endangerment of E uliginosus. However, there are very few differences between the two species. The diurnal activity was slightly longer in E cupreus than in E uliginosus. Flying potential was similar, but E cupreus seemed to be more efficient in reducing and regenerating flight muscles. Mobility and home-range was significantly higher and larger in E uliginosus than in E cupreus, with 0.7 m day~(-1), 0.5 m day~(-1), and 40 m~2, 9 m~2, respectively. Spatial use of both species differed considerably between years. Mobility decreased from spring to summer in E uliginosus. Although there are only few differences between species, it seems that E cupreus is more effective in using resources as it needs a significantly smaller home-range and lower mobility for its development. One reason for this difference may be the longer diurnal activity and the ability to reduce flight muscles in the summer season. Nevertheless, the good flight ability of E uliginosus shows that the species can reach adequate grassland patches in more than several hundred meters distance; thus, it can survive in wet grassland systems that have adequate habitat patches.