OBSERVATIONS ON LIFE-CYCLE AND FEEDING ECOLOGY OF 2 RECENTLY INTRODUCED PREDATORY BEETLE SPECIES AT SOUTH-GEORGIA, SUB-ANTARCTIC

On South Georgia, two recently introduced species of predatory beetle, Oopterus soledadinus and Trechisibus antarcticus (Coleoptera, Carabidae), were studied in the period November 1991-April 1992. The study area comprised the coastal area around Stromness Bay, in particular the surroundings of the abandoned whaling station at Husvik. The study investigated the life cycle of both species and, for T. antarcticus, aspects of feeding. The occurrence of both teneral and gravid beetles was observed for the whole of the summer period. Trechisibus antarcticus appeared to be the more voracious predator of the two; its impact on other populations of soil animals may be large as shown by its effect on the endemic detritivorous beetle Hydromedion sparsutum (Perimylopidae).