Population and distribution change of Eurasian Woodcocks Scolopax rusticola breeding in the UK: results of the 2023 Breeding Woodcock Survey.

Author Heward, C.J., Conway, G.J., Hoodless, A.N., Norfolk, D., & Aebischer, N. J.
Citation Heward, C.J., Conway, G.J., Hoodless, A.N., Norfolk, D., & Aebischer, N. J. (2024). Population and distribution change of Eurasian Woodcocks Scolopax rusticola breeding in the UK: results of the 2023 Breeding Woodcock Survey. Bird Study.

Abstract

Capsule: The UK breeding population estimate comprised 50,750 male Eurasian Woodcocks (95% CI: 42,935–59,251) in Britain and 937 males (95% CI: 274–1714) in Northern Ireland. The British population has continued to decline since 2013. Aim: To produce UK, British and regional estimates of breeding population size for Eurasian Woodcocks, and to assess the population change since 2003. Methods: The 2023 Breeding Woodcock Survey enlisted volunteer surveyors to count birds across a stratified sample of 1230 squares in England, Scotland, Wales, and Northern Ireland. The established ‘roding count’ methodology consists of up to three dusk visits, each lasting 75 min, during May and/or June. The results were used to calculate presence and mean density across 48 strata based on wooded area and regions, and extrapolated to produce regional and national estimates of population size. Results: The population in Britain in 2023 was estimated at 50,750 male Woodcocks (95 CI: 42,935–59,251), representing an 8% decline since 2013, and a 35% decline since 2003. Despite small population increases in Wales and England since 2013, the continuing decline was driven by a 49.5% reduction in the population estimate for North Scotland. In 2023, Northern Ireland’s breeding population of Eurasian Woodcocks was estimated at 937 males (95% CI: 274–1714), which is the first estimate produced using this species-specific method. Conclusion: Nationally, populations of Eurasian Woodcocks continue to decline, but the 2013–2023 declines were not as severe as those recorded between 2003 and 2013. The diverging population trends between North Scotland and the rest of Britain raise questions regarding regional variation in habitat suitability/availability and factors influencing overwinter survival. Recommendations are made for future versions of the Breeding Woodcock Survey regarding the composition of the random sample of squares, the treatment of incomplete data, and the sampling of non-woodland habitat.