Impacts of Habitat Fragmentation and Patch Size upon Migration Rates

Abstract

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. Ecological Society of America is collaborating with JSTOR to digitize, preserve and extend access to Ecological Applications. Abstract. A spatially explicit model (MIGRATE) was used to investigate the effects of habitat loss and fragmentation on the ability of species to migrate in response to climate change. Illustrative simulations were run using parameters that represent the reproductive and dispersal characteristics of the wind-dispersed tree Tilia cordata (small-leaved lime). Hierarchically structured landscapes with different patch sizes and overall habitat suitability levels were generated at a 1-km resolution for a 200 X 800 km area. Simulated migration rates slowed markedly when habitat availability fell below -25% of the landscape area, especially in landscapes composed of fewer larger patches. The implication of these results for the management of landscapes for species conservation is discussed.

Modeling vertical coral connectivity and mesophotic refugia

“…Further, the effects of habitat fragmentation on coral metapopulation connectivity are poorly understood and potentially severe (Tilman et al 1994;Collingham and Huntley 2000;Hanski and Ovaskainen 2000). Although the environmental conditions that determine the abundance and distribution of coral reefs may be restricted, the extent and degree to which local and global coral reef stressors may disturb coral reefs are not uniform in space.…”

Genetic population structure of the sagebrush Brewer’s sparrow, Spizella breweri breweri, in a fragmented landscape at the northern range periphery

“…Future climatic warming could become a major force in shifting species' distributions (Parmesan et al 1999), with habitat fragmentation potentially impeding a species shifting its range or moving to climatically more suitable locations (Kappelle et al 1999). If the dispersal abilities of a species are inadequate for surmounting the barriers imposed by habitat fragmentation, then there is an increased risk of population declines due to the interaction of habitat fragmentation and climate change and increased risk of extinction (Collingham and Huntley 2000). In response to increasing temperatures, many bird species have enlarged their distributions and colonized new habitats, especially at the northern range boundary (Thomas and Lennon 1999;Parmesan and Yohe 2003).…”

Tools for Conserving Managing Individual Plant Species in Dynamic Landscapes

“…Other dispersal models have been used from time to time, including the gamma, Weibull and normal distributions (e.g. Collingham & Huntley 2000;Yamamura 2002) and are sometimes based on explicit physical models (e.g. Schurr et al 2005).…”

“…Lavorel et al 1995;Collingham & Huntley 2000;Russo 2005;Schurr et al 2005). Alternative, 'fat-tailed' distributions predict plant dispersal much closer to observed patterns.…”