Response to comment on "Extinction debt and windows of conservation opportunity in the Brazilian Amazon".

Halley et al. purport to show a power-law relationship between fragment size and relaxation rates. We use a much more extensive data set to show that area dependence of relaxation rates exists only for very small fragment sizes (<60 hectares), which has limited relevance for our analyses conducted using 250,000-hectare grid squares. We also show that the example of Halley et al. is based on an unrealistic fragmentation model with an infinite number of fragments that have average size of zero hectares. A more realistic formulation of the model shows that relaxation is much less dependent on fragmentation than Halley et al. present.