The distribution and abundance of predatory arthropods overwintering on farmland

Abstract

SUMMARY Soil samples (0·04 m ‐2 ) were taken from December to January in 1981‐82 and 1982‐83 from five crop and two non‐crop habitats on farmland in Hampshire to quantify the distribution and abundance of overwintering polyphagous predatory arthropods. Total numbers of overwintering polyphagous predators were greater in field boundaries, winter‐sown cereals and established grassland than in the other four habitats. Many individual species overwintered in significantly higher densities in field boundaries than in any other habitat; others predominated in woodland, grassland and winter‐sown cereals. The carabids Agonum dorsale and Demetrias atricapillus , probably the most important predators of cereal aphids, overwintered almost entirely in field boundaries.