Biodiversity despite selective logging

[Extract] Primary tropical forests are powerhouses of biodiversity but are rapidly declining in extent and are threatened even within some protected areas. As a result, non-primary forests, especially those that have been selectively logged, are becoming more important to conservation efforts. In the tropics, logging is almost always selective, targeting only certain commercially valuable tree species above a minimum size and leaving other species unharvested. More than 400 million hectares of tropical forest are now in permanent timber estates, and at least 20% of all tropical forests were logged from 2000 to 2005. Biologists have often emphasized the deleterious impacts of selective logging for disturbance- sensitive wildlife, but recent evidence suggests that logged forests can have surprisingly high conservation values. In a meta-analysis across four tropical regions, selectively logged forests were by far the most biologically similar to primary forests, compared with agricultural and groforestry systems