Habitat use of the fungivorous beetle Bolitophagus reticulatus (Coleoptera: Tenebrionidae): Effects of basidiocarp size, humidity and competitors

Habitat use of Bolitophagus reticulatus (L.) (Coleoptera: Tenebrionidae), l iving in the basidiocarps of Fomes fomentarius (L.) Kickx, was investigated in three forest areas in south-eastern Norway: (1) a continuous, coniferou s forest, (2) an agricultural area with mostly deciduous forest islands in a matrix of cultivated land and (3) a homogeneous, old deciduous forest sta nd. B. reticulatus was almost exclusively found inside dead basidiocarps. T he size of the basidiocarp was the most important variable for predicting t he probability of B. reticulatus presence in the basidiocarps from all thre e study areas. Drier basidiocarps had a higher probability of beetle presen ce than the wetter ones. Basidiocarps situated above the ground level had a higher probability of beetle presence than those close to or on the ground level. In the first study area, the presence of Cisidae was found to reduc e the probability of B. reticulatus presence perhaps as a result of competi tion. The disappearance of beetles from previously inhabited basidiocarps s eemed to be due to depletion of resources.