Habitat fragmentation occurs when wildlife habitats change in area, configuration, or spatial relationships because of natural and anthropogenic mechanisms. Habitat fragmentation is arguably the greatest conservation challenge facing today?s wildlife biologists, of which most biologists are keenly aware because habitat is a unifying resource for most wildlife conservation efforts. For the past few decades, wildlife biologists have assessed effects of habitat fragmentation on wildlife while billions of public and private dollars have been spent on habitat acquisition and wildlife conservation efforts to offset the effects of fragmentation. Recently, however, the conceptual basis of habitat fragmentation has been questioned along with how it is assessed. The primary reasons for questioning the concept are: (1) ambiguity of the definition of fragmentation; (2) using a variety of ambiguous metrics to quantify fragmentation and difficulty in linking these metrics and wildlife response measures; (3) classifying habitat loss and habitat fragmentation as negative outcomes has led to confusion between the 2 because they are both a process and an outcome; (4) habitat heterogeneity and dynamics confound effects from fragmentation; (5) inherent complexity of ecological systems has led to confounding effects and multi-causal responses by wildlife; (6) species-specific responses to fragmentation has led to varied responses by wildlife; and (7) methodological problems exist with scientific assessments of the effects of fragmentation on wildlife. Fragmented habitats affect wildlife in negative, positive, and neutral ways depending on the mechanism, the magnitude, duration, frequency, and extent of the fragmentation, and habitat(s) and wildlife species affected. The interrelationship between loss and fragmentation also dictates wildlife responses. Assessments of fragmentation effects should focus on individual species because fragmentation occurs to habitats, and habitats are defined by individual species. Assessments involving multiple species should involve species that can represent the full range of impacts from fragmentation. Most research and conservation efforts have focused primarily on fragmentation as an outcome because fragmented landscapes of smaller habitat patches are obvious and immediate outcomes of fragmentation. The process of fragmentation must also be considered because attention is then focused on the spatial and temporal components of fragmentation.
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