ABSTRACT
Natural ecosystems worldwide are subjected to increasing amounts of external pressure, degradation, and fragmentation with significant consequences to global biodiversity (Heywood, 1995). Yet, even natural landscapes are not always uniform, and many species live as metapopulations comprising an assemblage of discrete local subpopulations linked by dispersal and gene flow (Hanski and Gilpin, 1997). As a result, defining habitat fragments can be difficult, and researchers working on different organisms or ecosystems often rely on discrete interpretations (Watson, 2002). Generally, though, habitat fragmentation involves the artificial dissection of the natural distribution of a single species or of a group of species representing a functional ecological unit. Fragmentation can have considerable consequences on the population dynamics, genetic diversity, and overall fitness of species and poses serious threats to the integrity and longterm sustainability of the entire ecosystem. Because of the severity of its consequences, particularly for highly diverse ecosystems, habitat fragmentation is a main concern of the international conservation agenda.
