Abstract

Long-term studies of two contrasting English woods reveal a complex picture of change in breeding bird communities. Bradfield Woods in Suffolk is managed coppice with high proportions of understorey-dependent species and migrants, whereas Sheephouse Wood in Buckinghamshire is predominantly high forest Pedunculate Oak Quercus robur with fewer migrants and more hole-nesters. Over four decades, change was more pronounced at Bradfield, largely due to declines of tropical migrants: Willow Warbler Phylloscopus trochilus, Common Nightingale Luscinia megarhynchos and Garden Warbler Sylvia borin. Willow Warblerwent from 64 territories in 1987 to absence by 2020. At Sheephouse, migrants showed similar trends, though densities were far lower. Among the resident species, Willow Tit Poecile montanus disappeared from both woods by the late 1990s, while Marsh Tit Poecile palustris and Common Chaffinch Fringilla coelebs declined in both. At Bradfield, the cyclical pattern of coppice growth was closely linked to species’ spatial dynamics, and increasing deer numbers there have reduced low foliage density, lowering habitat suitability for understorey species. In particular, deer browsing was implicated in the demise of Common Nightingale and probably the decline of Garden Warbler. At Sheephouse, ride widening and patch felling were associated with temporary increases in shrub-nesting birds. In both woods, canopy shading led to reduced complexity of low foliage and consequent simplification of bird communities. These changes in species composition mostly mirror those evident elsewhere in England and illustrate the dominating influence of human management on the character of bird communities. Maintaining diversity of habitat structures may offer the best hope for sustaining rich woodland bird populations. Rewilding has a role in delivering part of that, but maintaining substantial areas of young-growth will remain a major challenge in British woodland.