Habitat fragmentation affects movement and space use of a specialist folivore, the koala

Abstract

Habitat fragmentation changes landscape patterns and can disrupt many important ecological processes. Movement allows individuals to find resource patches to maintain their fitness and habitat fragmentation can disrupt this process. We explored the ecological impact of habitat fragmentation on movement and space use of a specialist folivore, the koala Phascolarctos cinereus. We GPS tracked koala movements within a fragmented agricultural landscape. We calculated the total distance moved across four months and the number of core patches by each koala. We used four metrics (proximity, functional connectivity, clumpiness, perimeter-to-area fractal dimension) to quantify landscape fragmentation within koala home ranges and determine its effects on movement and space use. Functional connectivity had the greatest effect on individual movement and space use. Decreasing connectivity led to longer and more direct movements by koalas and more core patches within an individual home range. Our study provides insight into the effects of habitat fragmentation on animal movement and space use, which can be used by wildlife managers to plan and manage landscapes more effectively.We conclude that restoring or protecting resource patches to promote greater functional connectivity will reduce the costs associated with the isolation of resource patches for species occupying fragmented landscapes. By providing a quantitative relationship between habitat connectivity and movement and space use costs, our results enable managers to set restoration targets, by identifying the most effective way to provide the functional connectivity minimizing the negative impact on focal species.