Sources

Fatal Attacks by American Black Bear on People: 1900–2009
Stephen Herrero, Andrew Higgins, James E. Cardoza, Laura I. Hajduk, and Tom S. Smith
Journal of Wildlife Management 2011 75 (3), 596-603

Conservation Biology and Carnivore Conservation in the Rocky Mountains Reed F. Noss, Howard B. Quigley, Maurice G. Hornocker, Troy Merrill and Paul C. Paquet Conservation Biology , Vol. 10, No. 4 (Aug., 1996), pp. 949-963

Range Contractions of North American Carnivores and Ungulates
ANDREA S. LALIBERTE and WILLIAM J. RIPPLE
BioScience2004 54 (2), 123-138

The Rise of the Mesopredator

Laura R. Prugh, Chantal J. Stoner, Clinton W. Epps, William T. Bean, William J. Ripple, Andrea S. Laliberte, and Justin S. Brashares

BioScience 2009 59 (9), 779-791

 

 

Trophic Downgrading of Planet Earth

James A. Estes, John Terborgh, Justin S. Brashares, Mary E. Power, Joel Berger, William J. Bond, Stephen R. Carpenter, Timothy E. Essington, Robert D. Holt, Jeremy B. C. Jackson, Robert J. Marquis, Lauri Oksanen, Tarja Oksanen, Robert T. Paine, Ellen K. Pikitch, William J. Ripple, Stuart A. Sandin, Marten Scheffer, Thomas W. Schoener, Jonathan B. Shurin, Anthony R. E. Sinclair, Michael E. Soulé, Risto Virtanen, and David A. Wardle

Science 15 July 2011: 333 (6040), 301-306. [DOI:10.1126/science.1205106]

Bergstrom, B. J. (January 01, 2011). Endangered wolves fall prey to politics. Science (New York, N.Y.), 333, 6046.)

 

 

Robert L. Beschta, William J. Ripple, Large predators and trophic cascades in terrestrial ecosystems of the western United States, Biological Conservation, Volume 142, Issue 11, November 2009, Pages 2401-2414, ISSN 0006-3207, 10.1016/j.biocon.2009.06.015.

(http://www.sciencedirect.com/science/article/pii/S0006320709002584)

"Wildlife Library." National Wildlife Federation. National Wildlife Federation. Web. 15 Feb. 2012. http://www.nwf.org/Wildlife/Wildlife-Library/Mammals/Gray-Wolf.aspx.

"Grizzly Bear." Defenders of Wildlife. Defenders of Wildlife. Web. 4 Mar. 2012. http://www.defenders.org/wildlife_and_habitat/wildlife/grizzly_bear.php.

"Cougar Conservation & Science." Mountain Lion, Cougar, Management, Science, Conservation: The Cougar Fund. The Cougar Fund. Web. 05 Mar. 2012. http://www.cougarfund.org/conservation/.

"News Releases - Beef USA." Beef USA. National Cattlemen's Beef Association, 7 Dec. 2010. Web. 05 Mar. 2012. http://www.beefusa.org/newsreleases1.aspx?newsid=2129.

Pictures:

Wolf Picture: http://www.petandwildlife.com/wolves/wolf_species.htm

Black Bear Picture: http://animal.discovery.com/mammals/black-bear/

Grizzly Bear Picture: http://www.bearhuntinginfo.com/bear-pictures.php

Mountain Lion Picture: http://www.ics.uci.edu/~eppstein/pix/josh3/MountainLion.html