Corridors keep plants and animals from becoming trapped on small patches of land, where they would suffer from inbreeding and other problems that affect small populations.
Beier has been involved in designing corridors in Arizona and California since 2002 and recruited McRae to develop a more rigorous scientific basis for designing corridors.
My worst nightmare is that scarce conservation dollars would be spent implementing my recommendations for a corridor, but then the corridor doesnt work, Beier said. Brads model provides a realistic way to look at connectivity of the entire landscape rather than just a small part of the landscape.
The resistance model incorporates multiple pathways, instead of just the most obvious one. It represents the landscape as a conductive surface, calculating all possible pathways connecting the patches. The PNAS article tested how well the new model explained genetic patterns across 12 wolverine populations across the United States and Canada, and eight big-leaf mahogany populations in Central America.
McRae and collaborators are now using the model to pinpoint critical linkages in landscapes and aid in conservation planning. If you can imagine current flowing across a landscape, areas where it concentratesbottlenecks or pinch points in the flowtypically correspond to important areas to maintain connectivity, McRae said. If you can distribute that current across multiple corridors, youll get greater connectivity, greater gene flow and greater robustness to climate change or catastrophes like wildfires.
|Contact: Paul Beier|
Northern Arizona University