1. Nicholas School of the Environment; University Program in Ecology; Duke University; Durham NC 27708 USA
2. Division of Biological Sciences; University of Montana; Missoula MT 59812 USA
3. Ecole Polytechnique Fédérale de Lausanne (EPFL); School of Architecture, Civil and Environmental Engineering (ENAC); Laboratory of Geographic Information Systems (LASIG); CH-1015 Lausanne Switzerland
4. Earth Institute, and Department of Ecology, Evolution & Environmental Biology; Columbia University; New York NY 10027 USA
5. Department of Biology; Pennsylvania State University; University Park PA 16802 USA