Trophic cascades in Yellowstone: the first 15 years after wolf reintroduction

The 97 images (supplementary data) that are part of this study were originally submitted to ScholarsArchive@OSU in April 2011, eight months before the article was deposited. The original url for the images is http://hdl.handle.net/1957/20842NEWS COVERAGE: A news release based on this journal publication, which is written for a lay audience and has been approved by an author of the study, is available online: http://bit.ly/s8aNqSThe 1995/96 reintroduction of gray wolves (Canis lupus) into Yellowstone National Park\ud after a 70 year absence has allowed for studies of tri-trophic cascades involving wolves, elk\ud (Cervus elaphus), and plant species such as aspen (Populus tremuloides), cottonwoods (Populus\ud spp.), and willows (Salix spp.). To investigate the status of this cascade, in September of 2010\ud we repeated an earlier survey of aspen and measured browsing and heights of young aspen in 97\ud stands along four streams in the Lamar River catchment of the park’s northern winter range. We\ud found that browsing on the five tallest young aspen in each stand decreased from 100% of all\ud measured leaders in 1998 to means of <25 % in the uplands and