| Summary: | In Britain, the Eurasian woodcock Scolopax rusticola occurs as both a common winter migrant and a resident breeding species. A national Breeding Woodcock Survey, conducted in 2003, provided the first accurate assessment of Britain’s resident population size. Here, data from a second national Breeding Woodcock Survey are presented, providing the first opportunity to assess changes in abundance. I estimated Britain’s Breeding population to be 55,241 males (95% CL: 41,806–69,004), representing a 29% decline in ten years. Abundance was correlated with the availability of large, well-connected and heterogenous areas of woodland and populations have retracted towards more heavily wooded landscapes. Woodcock site occupancy increases with the availability of certain woodland types, notably birch, and with increasing distance from urban areas.
The 2003 and 2013 Breeding Woodcock Surveys used counts of displaying male woodcock to estimate abundance across a stratified sample of randomly selected sites. Chapters 4 to 7 seek to improve the current understanding of this unique display, known as roding, which underpins national surveys in Britain and elsewhere in Europe. To do this, GPS loggers were used to track the movements of male woodcock during their roding flights. Male woodcock covered roding grounds that were larger in size than most previous estimates, with mean daily roding grounds measuring between 1.11 and 1.29 km2 depending on the technique employed. Roding activity was reduced if dry periods preceded roding surveys, and temperature, cloud and moon phase could all influence the timing of display. The woodcock’s roding display is targeted towards open space within woodlands and woodland edges, and woodcock showed a preference for permanent clearings during display. These findings are discussed in terms of their potential influence on the interpretation of existing roding survey data and their implications for future assessments of population size and trend.
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