Habitat correlates of Eurasian Woodcock Scolopax rusticola abundance in a declining resident population
Author(s): Heward, C.J., Hoodless, A.N., Conway, G.J., Fuller, R.J., MacColl, A.D.C. & Aebisher, N.J.
Published: 2 June 2018
Journal: Journal of Ornithology
Digital Identifier No. (DOI): 10.1007/s10336-018-1570-z
Woodcock, along with many other woodland bird populations, have been in long-term decline. Habitat change has been indicated as a possible cause for some species, but evidence is sparse for others, including Woodcock, due to an incomplete knowledge of their habitat requirements, which we can now examine.
National BTO/GWCT Woodcock surveys undertaken in 2003 and 2013 provided data from 807 and 823 randomly selected 1 km squares, respectively. Woodcock counts were compared with a range of landscape-scale habitat variables as well as local habitat measures recorded by surveyors, using generalised linear mixed models. Habitat variables were measured at a variety of spatial scales using ring buffers, however high correlation between scales limits interpretation.
The results show that, at large landscape scales, breeding Woodcock abundance was correlated with total woodland area and woodland type. Woodcock were more abundant in woods containing a more heterogeneous mix of woodland habitat types and in woods further from urban areas. On a smaller spatial scale, Woodcock were less likely to be found at sites dominated by Beech and more likely to occur in woods containing Birch.
The Woodcock’s association with large, heterogeneous woods and the apparent attractiveness of certain woodland types present the most relevant topics for future research into the role of habitat change in long-term declines.