Mobility, population size and life time pattern of Carabus glabratus (Coleoptera, Carabidae) under extreme northern forest conditions.

The study was carried out in the Varriotunturi fell area (67 degrees 44'N, 29 degrees 37'E) under northern taiga forest conditions. The habitat, a Pin us heath is extremely poor and monotonous. Altogether 196 pitfall traps 10 metres apart (circle divide 8.5 cm, height 10.3 cm, with a lid 5 cm above t he trap) arranged in a quadrat were used in 1991, and the same field with a n additional 40 traps placed one trap at each end of a two-metre wall was u sed from 1992 to 1994. The individuals of Carabus glabratus were marked wit h a small label cut off from a traffic sign sticker in 1991 and 1992. Only these captured and marked ones were recorded in the following years. In 199 4 the trapping was done by killing the beetles. 524 individuals were marked . Males dominated in both years. The recapture proportion was significantly higher for the beetles marked in 1992 than for those of the previous year. The marked beetles were recaptured within four days on average. The estima ted maximal population size in 1991 was 1400 individuals, occurring at the beginning of July, while in 1992 it was 3000 exx., in the middle of June. A bout 15% of the beetles marked in 1991 were caught at least once during the year of marking. Two years after marking, the proportion of recaptures dec reased to 2%, but one male marked in 1991 was still captured in 1994.