Short-term effects of wildfire on bird assemblages in old pine- and spruce-dominated forests in northern Sweden

Abstract

Effects of wildfire on forest birds have rarely been studied in Fennoscandia. Hence, birds were surveyed three years after fire at two large areas that were not subjected to salvage logging, in northern Sweden. The 300- and 440-ha burns and surrounding forests were dominated by Scots pine and Norway spruce, respectively. Closed-nest breeders and ground-feeding insectivores were more abundant within the burns than in the surrounding forests, whereas ground- and shrub-breeders were nearly equally abundant in the burns and in unburned forests. Redpoll and Tree Pipit were more common within than outside the burns. Birds feeding on insects in the air and the Redstart were more abundant in burned than in unburned spruce-dominated forest but no such difference was found in pine-dominated forest, suggesting that the short-term effects of wildfire on these birds were stronger in spruce-dominated forest than in pine-dominated forest. A contributing factor might be that crown fire killed most trees in the spruce-dominated burn, but most of the large trees survived the ground fire in the pine-dominated burn.