Ground beetles (Carabidae) of field margin habitats

The aim of this study was to identify the role of field margin habitats in preserving the diversity and abundance of ground beetle assemblages, including potentially entomophagous species and those with conservation status in Poland. Research material was collected in 2006–2007 in four types of margin habitats – a forest, bushes, ditches and in two arable fields. Insects were captured into pitfalls, without preservation liquid or bait added to the traps. Traps were inspected twice a week, between May and August, and one sample was a weekly capture. In field margin habitats the most abundant species were Limodromus assimilis, Anchomenus dorsalis, Pterostichus melanarius and Carabus auratus. A lower abundance of species was noted on fields, with dominant Poecilus cupreus and P. melanarius. The group of zoophagous carabids found in our study includes 30 species from field margin habitats, i.e. 37.5% of all captured Carabidae taxa and 58.3% of all specimens. The share of aphidophagous species was 84.9% among bushes, 86.7% near ditches, and 88.0% in the forest habitat. Several species captured during the study are under protection in Poland. These include the partly protected Carabus convexus, which also has the status of near threatened species, the partly protected Calosoma auropunctatum, and Broscus cephalotes. Considering all the investigated field margin habitats, ground beetles were most numerous in the oak-hornbeam habitat, defined as bushes, formed predominantly by Prunus spinosa, Crataegus leavigata, Sambucus nigra and Rosa canina. Thus, this habitat was the most important reservoir/refugium for the ground beetles.