Understanding the effects of habitat loss on population persistence

Habitat loss is the dominant threat to biodiversity worldwide. Habitat loss comes in the form of land conversion, where suitable habitat is changed into unsuitable space for vital life functions. The resulting landscape is a patchwork of disjoint habitat patches, varying in quality and connectedness with nearby patches. A major unknown is how much habitat loss species can tolerate before they are at risk of extinction, and whether the spatial distribution of remaining habitat matters. I will present a model of population dynamics in a network of connected subpopulations. To analyze the model, I will present framework for understanding the effects of habitat loss on species persistence that focuses on three factors: (1) the distribution of sizes of habitat patches, (2) the effects of converted habitat on local growth in remaining habitat patches, and (3) connectivity of the landscape. I’ll illustrate the value of the framework using numerical techniques in some simple landscapes and also in randomly constructed landscapes.