Print PageMovement patterns for some organisms are significantly constrained by topography, and in some situations topography can be the most important factor in determining least-cost paths across the landscape for organisms. Amphibians in desert regions are constrained in their surface movements because of thermal reaction norms and their naked and permeable skin. We present the first steps of a project evaluating desert wildlife water management and the effects of this management on diversity of wetland dependant species. We evaluated four methods for calculating least cost paths including using Mahalanobis distance, cross-sectional curvature, topographic position index, and flow accumulation and applied these methods to evaluating amphibian movements between water sites in the Sonoran Desert on the Barry M. Goldwater Range, US Air Force in south-western Arizona.
Results/Conclusions
We found that using values calculated from the Mahalanobis Distance was the most objective method and gave us the most realistic routes between potential breeding sites. Other methods tended to have paths crossing large numbers of ridge tops, or forced into unrealistic routes that were more mathematical constructs than actual features on the landscape. We discuss the application of least-cost path analysis to designing a landscape-based approach to managing wildlife waters in this desert region.
