A CircuitScape DISPERSAL MODEL AND INDEX FOR CONNECTIVITY IN SOUTH FLORIDA LANDSCAPES

CircuitScape is a unique approach to dispersal modeling that predicts paths and patterns of animal movements in heterogeneous landscapes using algorithms from electronic circuit theory. The approach links circuit and random walk theories based on the idea that corridors connecting habitats can be represented as current flows between electrical nodes. Multiple or wider corridors between habitats will have greater conductance than narrower paths. Because circuit theory can measure all possible pathways across a landscape simultaneously, it is being adapted as a particularly effective approach for evaluating impacts of development and landscape changes on mammal dispersal and habitat connectivity. To develop a useful landscape index, the impacts of landscape scale, extent and configuration on CircuitScape results in South Florida were tested. Results are presented in environments ranging from open habitat with increasing rock mine development to complex urban environments with intertwined natural corridors and habitat core areas. Methods for aggregating CircuitScape results into an index of connectivity are presented.