Spider assemblages in bird burrows

摘要: The arachnofauna of bird burrows, which are excavated in the soil, is incompletely understood. burrows have a potential to serve as refugia for cavity-adopting spider species particularly anthropogenic habitats formed by sand mining, otherwise suffer from limited availability other types cavities. We hypothesized that presence abundant food resources and safe shelter soil allow existence specialized assemblage spiders, similarly those known cavities nests made birds mammals. Here we examined 353 had been previously occupied Riparia riparia, Merops apiaster or Passer montanus. were early May September 24 Czech pits construction sites. hosted species-rich spiders that, however, occurred at low abundances. represented prevalently distributions centered urban habitats, including never observed outside heated buildings study area only mammalian loess karstic crevices. Spider assemblages strongly differed between composition overall abundance was unexpected strong contrast previous observations Concluded, rejected initial hypothesis and, instead, shown rarely if occupied, adopt old inside them predominantly consist their distribution habitats.