Habitat use by Woodcock Scolopax rusticola during the breeding season.

Abstract

The aim of this study in Whitwell Wood, Derbyshire, England was to identify the habitat features which influence where woodcock feed, nest and display (rode) during the breeding season.

Vegetation structure and composition, soil parameters and earthworm numbers (30 variables) were recorded for quadrats containing 50 feeding locations of six radio-tagged birds and then compared with the same information for 50 locations chosen at random. Observations of roding woodcock were made in three sectors of the wood with different dominant overstorey species. The average number of roding contacts in each area, and the extent to which nine radio-tagged males roded over them, was then compared to the number of nests found in the sectors over a series of years.

Both feeding sites and nests occurred disproportionately in sycamore stands. Areas where beech and pine dominated the overstorey tended to be avoided by feeding birds and no nests were found under beech after April.

Significantly different distribution values between feeding and random sites were found for 11 habitat variables. Feeding sites were in younger stands with a higher percentage ground cover of dog's mercury (Mercurialis perennis) and consistently high values for pH. Earthworm biomass was on average 82% greater than in random plots. A discriminant function based on 6 habitat variables correctly classified 85.5% of the feeding and random sites.

Roding intensity differed significantly between different areas of the wood, partly because some individual males displayed more over some parts of the wood than others. The area over which most birds displayed consists largely of sycamore and has contained 77% of the nests located in Whitwell.

The results of this study indicate that habitat type and structure, and food availability all influence where woodcock feed, nest and display during the breeding season.