1. Cornell Lab of Ornithology, Cornell University Museum of Vertebrates , Ithaca, NY , United States
2. Department of Evolution and Ecology, University of California , Davis, CA , United States
3. Department of Biology, Saint Louis University , St. Louis, MO , United States
4. National Great Rivers Research and Education Center , East Alton, IL , United States
5. Department of Ecology and Evolutionary Biology, Cornell University Museum of Vertebrates, Cornell University , Ithaca, NY , United States