The Adequacy of Some Collecting Techniques for Obtaining Representative Arthropod Sample in Dry Grasslands

Abstract

The number of remarkable species on a locality is an important indicator of locality value. The ecological requirements of the rare species may help to target correct landscape management activities. Our objective was to find out if standardly used capture methods for different group of invertebrate are able to detect really representative composition of species including rare taxa. Our experiment was carried out at the Moravský kras Protected Landscape Area (Macošská and Vilémovická stráň slope) where secondary dry grasslands are typical for each investigated locality. We used five groups of invertebrates (spiders, ground beetles, rove beetles, leaf beetles and weevils) and three capture methods (pitfall traps, sweeping on vegetation and yellow Möricke traps). Arthropods were determined and classified according to their rarity. Using the three capture methods, we obtained in total 127 spider species (Areneae), 31 ground beetle species (Carabidae), 29 rove beetle species (Staphylinide), 52 leaf beetle species (Chrysomelidae) and 55 weevil species (Curculionidae).Results showed that the different capture methods significantly influenced number of detected remarkable species. It was statistically proved for spiders (P = 0.025), weevils (P = 0.038) and marginally also for rove beetles (P = 0.051). Spiders of climax (C species) and semi-natural (SN species) habitats were rather detected by pitfall traps, whereas spiders of disturbed habitats were collected by sweeping on vegetation and Möricke yellow pans eventually. Relict species of weevils (R species) were detected by pitfall traps, typical species (T species) were collected by Möricke yellow pans and expansive species (E species) were found by sweeping on vegetation.