Spider assemblages on tree trunks in primeval deciduous forests of the Bialowieza National Park in eastern Poland

We analysed spider assemblages of tree trunks in an oak-lime-hornbeam forest, an ash-alder riparian forest and an alder carr in the primeval stands of the Bialowieza National Park. Spiders were collected from June 1998 to October 2000 using bark traps. A total of 2,182 spider individuals, belonging to 43 species and 14 families was collected. The forest types differed in the spider abundance and species richness. The differences probably resulted from different tree species and different environmental conditions in the forest types. The most numerous species in oak-lime-hornbeam forest and in alder can was Amaurobius fenestralis, whereas Anyphaena accentuata was the most abundant species in ash-alder riparian forest. Four species (Amaurobius fenestralis, Anyphaena accentuata, Segestria senoculata and Neriene montana) were collected in each month (March-October), whereas most species were recorded sporadically or in some periods.