THE INFLUENCE OF 4 DIFFERENT PREDATORS ON BARK BEETLES IN EUROPEAN FOREST ECOSYSTEMS (COLEOPTERA, SCOLYTIDAE)

Field and laboratory work was carried out to study the possible impact of 4 different species of bark beetle enemies. These are Scoloposceli s pulchella Zetterstedt 1838 [Heteroptera: Anthocoridae], Thanasimus f ormicarius Linnaeus 1758 [Coleoptera: Cleridae] Nemosoma elongatum Lin naeus 1761 [Coleoptera: Ostomidae] and Medetera dendrobaena Kowarz 187 7 [Diptera: Dolichopodidae]. These species are preying upon many bark beetles. The main prey species of N elongatum and M dendrobaena are Pi tyogenes chalcographus Linnaeus 1758 [Coleoptera: Scolytidae] and Taph rorychus bicolor Herbst 1793 [Coleoptera: Scolytidae], S pulchella mai nly attacks P chalcographus. On spruce the bark beetle Ips typographus Linnaeus 1758 [Coleoptera: Scolytidae] is one of the most important p rey species of T formicarius. The predator and the bark beetle species were reared in the laboratory to gain information about their biology . The Scolytidae were also reared to provide an adequate food supply f or the predators. In the laboratory, the egg production of the predato r species and the prey consumption during their larval development wer e determined. Furthermore, the densities and the voltinism of the anta gonists and of the bark beetles were investigated. Calculations to est imate the predator capacity of the 4 antagonistic species were perform ed. Based on this data the role of S pulchella, T formicarius, N elong atum and N dendrobaena in bark beetle regulation is discussed.