Population-dynamics and predator-prey-interaction between the predator Nemosoma elongatum and the bark beetle species Pityogenes chalcographus (Coleoptera: Ostomidae, Scolytidae).

Population-dynamics of the predator Nemosoma elongatum Linnaeus 1758 and of the bark beetle Pityogenes chalcographus Linnaeus 1758 were investigated with pheromone traps in different conifer-stands in 1991-1993. The proportion of predators in traps baited with Chalcoprax varies considerably between 1991 and 1993 with a local maximum of 20%. The population of Nemosoma elongatum increases earlier in spring than that of Pityogenes chalcographus, so reduction of the bark beetle population by predation may therefore be relatively high in V and VI.