Allee effects and extinction debt

Habitat destruction may have profound negative impacts on the biodiversity of a given environment. The presence of Allee effects compounds these problems. A sound understanding of the interplay between habitat destruction, Allee effects, and subsequent extinctions is needed to better guide conversation efforts. This study incorporates Allee effects into an extinction debt model, and the analyses provide upper bounds on the strength of those effects that are consistent with species persistence. These results differ from those of a previous study by up to four orders of magnitude assuming the same published parameter values. These new results suggest that if sufficiently strong Allee effects are present, efforts to prevent extinction through habitat restoration may be futile. (C) 2010 Elsevier B.V. All rights reserved.