Describing habitat occupation by woodland birds with territory mapping and remotely sensed data: an example using the marsh tit (Poecile palustris)

摘要

Changes in the structure of woodlands and forests, caused by shifts in management, stand maturity, and composition, have been implicated in the population decline of some bird species in Europe and North America. One such species is the Marsh Tit (Poecile palustris). We investigated relationships between Marsh Tit occupation (derived from territory mapping) and vegetation structure, tree species composition, and proximity to woodland edge in a British woodland, using a combination of 5 years of occupation data and high-resolution (0.5 and 1 m), large-scale (155 ha) habitat models derived from remote sensing. The results demonstrated that Marsh Tit occupation was linked to vegetation characteristics through the woodland's full vertical profile and related significantly and positively with overstory height, tree canopy closure, and the coverage of understory vegetation below the overstory. Marsh Tit occupation was lower within 50 m of the woodland perimeter, where habitat structure was less favorable than in the woodland interior. No preference was shown for areas rich in any particular prevalent tree species. Our results suggest that widespread changes in woodland structure resulting from abandonment by managers are unlikely to be responsible for the decline of the Marsh Tit in Britain and that reintroduction of active management that prevents woodland maturation could be detrimental to remaining populations. The study demonstrates a novel approach to integrating territory maps and remote-sensing data to permit highly detailed analyses of bird–habitat interactions and may have wider implications for woodland management and related bird species.