The conservation importance of luxuriant tree plantations for lower storey forest birds in south-west Ghana

Summary The exceptionally rapid degradation and fragmentation of the Upper Guinea Forest, caused by slash-and-burn farming and selective logging, oblige bird conservationists to examine critically the conservation value of unprotected areas, which may provide buffer zones or connecting corridors to protected forests. This paper assesses the utilisation of various tree-crop plantations by mainly lower storey forest birds in south-west Ghana, through avifaunal comparisons of shaded cash crops (rustic cocoa; neglected coconut) and exotic tree plantations (Cedrela, Gmelina) with nearby closed forest. Plantations adjacent to, or within, large (>200 km2), biodiverse forests are superior bird habitats compared to similar plantations within small (<50 km2) and species-poor forests. A relatively high forest tree density in cash crop (15–20 ha−1) and exotic (15–35 ha−1) tree plantations, combined with a luxuriant woody undergrowth (not slashed for >5–10 years), may additionally explain the presence of many forest specialists, including regionally ‘Vulnerable’ and locally ‘Endangered’ species. Overall, 50% of species of conservation importance found in forests were represented in plantations. These findings highlight the importance of shaded plantations with long periods between understorey weeding, as appropriate land-use systems that enhance the area under effective conservation and improve the connectivity of protected forest fragments. Results are compared to similar studies in the Old and New World tropics, and implications for off-reserve land-use management are compared and discussed in regional and global contexts.