Variability of Selected Traits of Ips Typographus (L.) (Col.: Scolytinae) Populations In Beskid Żwiecki (Western Carpathians, Poland) Region Affected By Bark Beetle Outbreak

In 2010-2012, investigations on Ips typographus populations were carried out in Norway spruce stands recently affected by bark beetle outbreak in the Beskid Żywiecki Mts. in Poland. The aim of the study was to test the usefulness of several traits describing I. typographus populations for evaluation of their actual outbreak tendency. Infestation density, sex ratio, gallery length, progeny number and beetle length were used as the traits. Trait variability was analyzed in relation to infested tree mortality in the current year of observation and outbreak tendency defined by the comparison of data on tree mortality in the current year and that in the year before