1. Monitoring Department Swiss Ornithological Institute Seerose 1 Sempach CH‐6204 Switzerland
2. Department of Fisheries and Wildlife Oregon State University 104 Nash Hall Corvallis OR 97331 U.S.A.
3. Cornell Lab of Ornithology 159 Sapsucker Woods Rd. Ithaca New York NY 14850 U.S.A.
4. Lane County Parks 3050 N. Delta Hwy Eugene OR 97408 U.S.A.