Habitat characteristics of wintering Wood Warbler Phylloscopus sibilatrix in the Centre Region of Cameroon: conservation implications

Populations of many Afro-Palearctic birds have declined, with those wintering in sub-Saharan Africa, such as Wood Warbler Phylloscopus sibilatrix, particularly affected. In this study we investigated the relationship between habitat characteristics and Wood Warbler presence/absence in the Centre Region of Cameroon. A total of six transects were established in three habitat types (forest, forest-savanna transitional zone and savanna). Call playback surveys were conducted monthly from November 2015 to April 2016 to determine Wood Warbler presence/absence. Detailed habitat measurements were also recorded in each transect. A total of 86 responses were recorded: 33 (mean 6.6 2.3) in forest habitat, 47 (mean 9.4 +/- 3.36) in the forest-savanna transitional zone, and 6 (mean 2 +/- 1.1) in savanna habitat. Wood Warbler presence increased significantly with the number of trees between 3 and 7 m in height, and decreased significantly with the number of shrubs between 0.5 and 3 m in height. Anthropogenic disturbance such as the agricultural cycle and burning were not found to have an effect on Wood Warblers presence/absence. We conclude that Wood Warblers overwinter in all three habitat types with probability of detection greatest in the forest-savanna transitional habitat with a relatively low canopy and an open understorey. Forest clearance in sub-Saharan Africa potentially threatens wintering habitat for Wood Warblers.