The short-term impact of fire on the beetle fauna in boreal coniferous forest

The immediate changes caused by forest fire in the beetle fauna were studied at three sites in boreal coniferous forest in Finland. In general the number of individuals and species increased after fire. The species attracted to the burnt forest included wood borers (Cerambycidae, Curculionidae, Anobiidae, some Elateridae), species develop ing under bark of damaged trees, species associated with fungi (Lathrididae, Crypto phagidae, Nitidulidae, Leiodidae) and certain soiland litter-dwelling groups: Carabidae, Byrrhidae and some Elateridae. Predators utilizing diptera larvae in mushrooms increased strongly after the fire as well. Many of the species presumed to be associated with wood-fungi peaked immediately after the fire, i.e. many cryptophagids, lathridids and nitidulids, whereas the leiodids Anisotoma spp. and Agathidium spp. became com moner two years after the fire. Several species previously known to strongly prefer burnt forests were captured. The fire specialists form a hetergenous ecological group, indicating that a substantial portion of the forest species have adapted to fire cycles. A large group of species normally found only in man-made, microclimatically warm habitats, e.g. compost, were attracted to two of the burnt sites. Their absence from the third site was probably due to lack of suitable source areas in the immediate surroundings. Cholevidae associated with rodents and many litter-dwelling Staphylinidae were drastically reduced by the fire. In most cases, their numbers had not returned to previous levels two years after the burning.