THE FIRST RECORD OF IPS DUPLICATUS (COLEOPTERA: CURCULIONIDAE, SCOLYTINAE) INFESTATIONS IN CENTRAL EUROPEAN INNER MOUNTAINS

The natural distribution of the double-spined spruce bark beetle, Ips duplicatus, includes the Palearctic stretching from Scandinavia across NE and Central Europe to NE Asia. The first outbreak of I. duplicatus in Central Europe probably occurred in the early 1990s in North Moravia and Silesia, where the beetle still infests spruces at elevations < 600 m a.s.l. This species, which prefers elevations < 600 m a.s.l., has not been previously found within large mountain ranges. The present study, however, deals with I. duplicatus occurrence at ca. 600 m a.s.l. in two large mountain ranges – the Moravskoslezské Beskydy Mts. and the Hrub? Jesen?k Mts. In both the regions, the beetle was detected in the terminal parts of closed valleys, approximately 20 km south of the infested sites at 400 m a.s.l. The new infestations at 600 m a.s.l. probably result from the increased abundance of the beetle in the lowlands of the closed valleys. The only defence currently known is to identify and harvest (destroy) the infested trees before offspring mature and overwinter in the litter. Occurrence of I. duplicatus within large mountain ranges constitutes a new risk for spruce stands in the mountains, at least in the Abieto-Fagetum forest vegetation (altitudinal) zone.