In the Bavarian Forest national park, the spruce bark beetle Ips typographus (Col., Scolytidae) has caused an uncontrolled mass propagation for more than 10 years. To find out if the population of parasitoid species, which can develop in an uncontrolled natural forest, is able to restrict spruce bark beetle gradation, we investigated the parasitoid fauna, their abundance and frequency in the central part of the park (no control), in the protection area and the enlargement area of the park and in a productive forest where the spruce bark beetle is strictly controlled. In 2002 and 2003, the species Coeloides bostrichorum, Roptrocerus xylophagorum/mirus, Rhopalicus tutela, Tomicobia seitneri and Dendrosoter eupterus were identified. C. bostrichorum was the most numerous species before Roptrocerus sp. and Rh. tutela. T. seitneri and D. eupterus were not as numerous. The order of frequency differed. Roptrocerus sp. was the most frequent parasitoid wasp in both years, and Rh. tutela and even T. seitneri were more frequent than C. bostrichorum. C. bostrichorum and Rh. tutela were found to be protandrous, whereas Roptrocerus sp. males and females had different sequences of appearance in different forest types. The average percentages of parasitism increased with time of exposure and was highest in the second generation. We found astonishingly high parasitization rates at sites where attacked trees are regularly removed.

Frequency, species composition and efficiency of Ips typographus (Col., Scolytidae) parasitoids in infested spruce forests in the National Park ''Bavarian Forest'' over three consecutive years Abstract During the summers of three consecutive years (2002, 2003 and 2004) the parasitoid fauna of the spruce bark beetle Ips typographus was investigated in the national park ''Bavarian Forest''. In the central part of this forest no human influence in the population dynamics is allowed, whereas, in the surrounding no bark beetle attacks are accepted and all infested wood is removed consequently. Species frequency and species composition did not differ much in 2002 and 2003, when Coeloides bostrichorum and Roptrocerus sp. was most numerous. But in 2004 species composition changed with the increase of R. tutela and the decrease of C. bostrichorum. We found that C. bostrichorum reached very high numbers of individuals, but its frequency did not exceed 31% during 3 years while the pteromalid wasps were not so numerous, but had very high frequencies.For Roptrocerus, we found 55, 82 and 85% and for R. tutela 41, 67 and 85% frequency. In 2004, mean parasitization was higher (8.5) as in 2003 (5.8%). The highest parasitization in one sample was 92.2% in 2002 caused by C. bostrichorum, 73.5% in 2003 caused by C. bostrichorum and R. tutela and 59.8% in 2004 caused by R. tutela and Roptrocerus. Our hypothesis that the influence of parasitoids on the population dynamics of I. typographus is greater in natural forests than in normal treated forests could not be corroborated.

Investigations into the flight behaviour of the male nun moth (Lymuntriu monucka L.) in different forest areas with the aid of electronic data recording equipment were carried out using pheromone baited traps. It was shown that according to the geographical area in which the observations were made, independent, however, from the type of forest, clear differences in the times of flight activity exist. These differences were maintained over an observation period of 2 years.

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