title: Age-area scaling of extinction debt within isolated terrestrial vertebrate assemblages.
abstract: A new model of delayed species loss (extinction debt) within isolated communities is applied to a large data set of terrestrial vertebrate assemblages (n = 188) occupying habitat fragments or islands varying greatly in size and age. The model encapsulates previous approaches based on diversity-dependent (DD) extinction rates while allowing for a more flexible treatment of temporal dynamics. Three important results emerge. First, species loss rate slows down with the age of the isolate, a strong and general pattern largely unnoticed so far. Secondly, while being good candidates in the light of previous works, DD models fail to account for this pattern, a result that necessitates a search for other mechanisms. Thirdly, a simple diversity-independent model based on area (converted into population size) and age explains 97% of the variability in species loss rate and appears to be a promising predictive tool to handle extinction debt following habitat loss.
authors.affiliation: UMR BOREA, MNHN, IRD 207, CNRS 7208, UPMC, Muséum National d'Histoire Naturelle, 43 rue Cuvier, FR-75231, Paris Cedex, France.
authors.forename: Bernard
authors.initials: B
authors.lastname: Hugueny
mesh_terms: D000818:Animals; D044822:Biodiversity; D003247:Conservation of Natural Resources; D017753:Ecosystem; D053476:Extinction, Biological; D062312:Islands; D008962:Models, Theoretical; D011156:Population Density; D014714:Vertebrates / Q000502:physiology*
keywords: Amphibians; birds; conservation biology; diversity dependence; habitat fragmentation; insular biogeography; mammals; relaxation; reptiles