Biological corridors and connectivity

The goal of this chapter is to describe the state of the art in quantitative corridor and connectivity modelling. It reviews several critical issues in modelling, and provides expert guidance and examples to help practitioners implement effective programmes to preserve, enhance or create connectivity among wildlife populations. It first reviews the fundamental task of estimating landscape resistance, comparing expert opinion and empirical methods. Next, it describes current methods of predicting connectivity from resistance surfaces. It concludes with discussion of how effectively to validate connectivity model predictions. In recent years least-cost (LC) modelling has become the dominant modelling tool to evaluate functional landscape connectivity, especially in applied studies. Advances in computing have allowed applications of graph algorithms to continuous landscapes instead of simple networks. Circuit and LC models represent two extremes in assumptions about movement and connectivity. A promising graph-theoretic approach to connectivity modelling is centrality analysis.