The application of island theory to fragmented landscapes

Abstract

Abstract ‘The application of island theory to fragmented landscapes’ considers the implications of the widespread fragmentation of natural habitats globally and the application of island theory to inform conservation. It explores the concept of minimum viable populations and how they translate into minimum viable areas for population persistence. It reviews the application of incidence functions and metapopulation theory (and variants describing persistent source–sink relationships) to the occupancy of habitat islands. It reviews evidence for extinction debts, species relaxation (richness reduction), threshold effects, and the habitat amount hypothesis. It traces the development of the ‘single large or several small’ reserves debate from its initial theoretical origins to an increasingly pragmatic research theme. It reviews the prevalence and significance of nestedness within habitat island systems, the roles of edge effects, habitat corridors, and landscape matrix effects. It briefly reviews links between island theory and other conservation themes, such as rewilding and land-sharing versus land-sparing.