Refocusing Habitat Fragmentation Research Using Lessons from the Last Decade

Abstract

Habitat alteration is broadly thought to be a primary threat to global biodiversity and has become the dominant topic for conservation biology. However, it is a complex process typically resulting in concurrent loss and increased fragmentation of remaining habitat. Researchers traditionally combined both these processes under a single umbrella term, ‘habitat fragmentation’, but this practice has ignited a contentious debate since the early 2000s. Over a decade has now past since the emergence of arguments that conservation insight could only be gained by considering loss and fragmentation as independent processes. We examine habitat fragmentation research since these calls for change, and assess the degree to which testing the independent effects of habitat loss and configuration on biodiversity has occurred in the scientific literature. We have found that only modest progress has been made toward this goal (i.e., 18 % of studies) and the majority of researchers continue to treat habitat loss and fragmentation as a single indistinguishable process. We argue that use of consistent definitions and approaches to uncovering specific fragmentation effects is particularly relevant in an era of accelerated human encroachment on natural habitats. Rigorous science on the response by biodiversity to the independent effects of habitat loss and fragmentation provides policy makers with the opportunity to optimize conservation planning efforts. We provide guidelines for how sampling designs and analyses can overcome existing challenges and researchers can search for generality in responses of biodiversity to habitat fragmentation.