Beschta and Ripple Scientific Papers
PDFs of all of the main articles cited in this Issue, including those from which figures were used (marked by *). Links to these and more related articles at: http://www.cof.orst.edu/cascades/articles.php

*Ripple, W.J. and Beschta, R.L. 2007. Restoring Yellowstone's aspen with wolves. Biological Conservation 138, June 2007: 514-519.

Beschta, Robert L., and Ripple, William J. 2007. Increased willow heights along northern Yellowstone's Blacktail Deer Creek following wolf reintroduction. Western North American Naturalist 67(4), 2007: 613-617.

Ripple, W.J. and Beschta, R.L. 2006. Linking wolves to willows via risk-sensitive foraging by ungulates in the northern Yellowstone ecosystem. Forest Ecology and Management 230, 2006: 96-106.

Beschta, R.L. 2005. Reduced cottonwood recruitment following extirpation of wolves in Yellowstone's Northern Range. Ecology 86(2), 2005: 391-403.

Ripple, W.J. and Beschta, R.L. 2005. Willow thickets protect young aspen from elk browsing after wolf reintroduction. Western North American Naturalist 65(1), 2005: 118-122.

*Ripple, W.J. and Beschta, R.L. 2004a. Wolves, elk, willows, and trophic cascades in the upper Gallatin Range of southwestern Montana, USA. Forest Ecology and Management 200, 2004: 161-181.

*Ripple, William J. and Beschta, Robert L 2004b. Wolves and the ecology of fear: Can predation risk structure ecosystems? BioScience Vo.l 54 No. 8, August 2004: 755-766.

*Beschta, R.L. 2003. Cottonwoods, elk, and wolves in the Lamar Valley of Yellowstone National Park. Ecological Applications 13(5), 2003: 1295-1309.

Concept Mapping
Explanations and examples of how to build concept maps and their utility for teaching:
How to construct a concept map
(http://www.udel.edu/chem/white/teaching/ConceptMap.html )

Concept mapping
(http://www.cotf.edu/ete/pbl2.html )

The Concept mapping homepage
(http://users.edte.utwente.nl/lanzing/cm_home.htm )

Good photos of cottonwoods as well as general background information.
Narrowleaf cottonwood. USDA & NRCS Plant Guide.
(http://plants.usda.gov/plantguide/doc/cs_poan3.doc )

Applied Animal Behavior Project of the University of Idaho and Washington State University. - general information on elk behavior
(http://www.cnr.uidaho.edu/range556/Appl_BEHAVE/ )

Wild Nature Images. Great photos of elk and other wildlife.
(http://www.wildnatureimages.com/elk%202%20Y.htm )

Yellowstone Elk. Yellowstone National Park. Information on the history of elk populations in the Park, as well as their interactions with human visitors.
(http://www.nps.gov/yell/naturescience/elk.htm )

Related Newspaper and Magazine Articles
Environmental Magazine - Good article to show the human side of science, and how Ripple and Beschta stumbled onto the trophic cascade issue in Yellowstone
(http://findarticles.com/p/articles/mi_m1594/is_2_17?pnum=3&opg=n16129805 )

National Wildlife Federation - Good general article about Ripple, Beschta and other scientists working on the trophic cascade question in Yellowstone
(http://www.nwf.org/nationalwildlife/article.cfm?articleId=829&issueId=69 )

Mystery in Yellowstone: wolves, wapiti, and the case of the disappearing aspen. Notable Notes, Oregon State University 2004.

New York Times - Good general article about the trophic cascade question and wolves in Yellowstone
(http://www.nytimes.com/2005/10/18/science/earth/18wolf.html )

High Country News - Short article about scientific debate surrounding wolf trophic cascade in Yellowstone, and alternative explanations for increase in willow cover
(http://www.hcn.org/servlets/hcn.Article?article_id=17471 )

Trophic Cascades
History of the concept, background information, and links to many related articles.
Oregon State University College of Forestry - Trophic Cascades Program
(http://www.cof.orst.edu/leopold/ )

Ripple, W.J. and Beschta, R.L. Linking Wolves and Plants: Aldo Leopold on trophic cascades. BioScience Vol. 55 No. 7, July 2005: 613-621.

UC Berkeley News story about benefit to scavengers of wolf kills in Greater Yellowstone Ecosystem.
( http://www.berkeley.edu/news/media/releases/2003/11/04_wolves.shtml )

Wild Nature Images. Great photos of wolves and other wildlife.
(http://www.wildnatureimages.com/Wolf_and_Bear.htm )

Information on the history of wolf restoration in Yellowstone National Park, including details of their interactions with and impact upon elk and other ungulates, other predators, livestock, human visitors and ranchers:
Wolves of Yellowstone. Yellowstone National Park.
(http://www.nps.gov/yell/naturescience/wolves.htm )

Ten Years of Yellowstone Wolves. Yellowstone Science.
(http://www.nps.gov/yell/planyourvisit/upload/YS13(1).pdf )

Yellowstone National Park
General information on and photos of Yellowstone National Park and its history.

Yellowstone National Park. Wikipedia.
(http://en.wikipedia.org/wiki/Yellowstone_National_Park )

Yellowstone National Park. National Park Service official site.
(http://www.nps.gov/yell/index.htm )