Behavioural, reproductive and developmental seasonality in Carabus auronitens and Carabus nemoralis (Col., Carabidae) : A demographic comparison between two co-existing spring breeding populations and tests for intra- and interspecific competition and for synchronizing weather events

Berlin

2001

192 S.

zahlr. Abb, Tab., Lit. Ang.

Bandaufführung

79174

In this paper we check for possible effects of intra- und interspecific competition within a Carabus asemblage consisting of Carabus (Chrysocarabus) auronitens Fabricius 1792 and Carabus (Archicarabus) nemoralis Müller 1764. Both species are spring breeders with summer larvae and obligatory activity in search of food after hatching in late summer/early autumn ("autumn season"). An individual marking-recapture experiment has been performed with C. auronitens since spring 1982; specimens of C. nemoralis were individually marked since spring 1992. The area of investigation (0.2 ha) was inside an oak-hornbeam forest of the Westphalian Lowlands (near the city of Münster). From spring 1982 until spring 1992 the area of investigation was surrounded by a fence that was not beetle-proof; in summer 1992 a beetle-proof fence was erected. In spring 1982 114 pitfall traps were set in this area; in autumn 1988 the number was increased to 152 traps, and in spring 1989 to 171 traps (Ø of a trap: 9,5 cm). During the activity seasons of the beetles the traps were usually opened twice a week overnight. The season evaluated for this paper extend up to the autumn season 1998; some data from the srping season 1999 are also considered.