The aim of this thesis is to inform readers about the influence of temperature and bioclimatic conditions on the size and spread of the spruce bark beetle population in the area of Orava Beskydy. To establish the beginning of spring swarming, to create a theoretical course of the development of individual ontogenetic stages, to determine the possible number of generations that the spruce bark beetle is able to raise in the climatic conditions of the Orava Beskydy. Establishment of experimental measurements of the air and bark temperature needed to calculate the theoretical development of the stages and to determine the term of spring swarming, based on the method of achieving a certain amount of effective temperature. The suggestion of possible measures to mitigate the consequences of bark beetle calamity.