1 Global Trophic Cascades Program, Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331; bill.ripple@oregonstate.edu.
2 Global Trophic Cascades Program, Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331.
3 School of Life and Environmental Sciences, The University of Sydney, Sydney, NSW 2006, Australia.
4 School of Environmental and Forest Sciences, University of Washington, Seattle, WA 98195.
5 Conservation Programmes, Zoological Society of London, London NW1 4RY, United Kingdom.
6 Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, CA 93106.