Colonization and the estimation of population size in the bark‐beetle Hylesinus varius (Coleoptera: Scolytidae), a pest of olives in southern Spain

Abstract This paper describes both the colonization process and a method for estimating popular size in Hylesinus varius a scolytid pest of various plant species including ash and olive. The colonization process occurs in two phases; during the first phase the construction of maternal feeding galleries induces a response by the tree which leads to the appearance of tumerous thickenings of the bark (so‐called ‘roses'); in the second phase further feeding galleries are constructed in the same roses and also at new sites on the tree. Population size in the olive grove (100 ha) was estimated to be 147700 adults, with a 1:1 sex ratio. The results obtained in this work are considered essential for the study of the dynamics of the H. varius population and for developing optimal control of the pest.