Ecology and Conservation of Cougars in the Eastern Great Basin: Effects of Urbanization, Habitat Fragmentation, and Exploitation
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Utah State University DigitalCommons@USU All Graduate Theses and Dissertations Graduate Studies 5-2011 Ecology and Conservation of Cougars in the Eastern Great Basin: Effects of Urbanization, Habitat Fragmentation, and Exploitation David C. Stoner Utah State University Follow this and additional works at: https://digitalcommons.usu.edu/etd Part of the Ecology and Evolutionary Biology Commons Recommended Citation Stoner, David C., "Ecology and Conservation of Cougars in the Eastern Great Basin: Effects of Urbanization, Habitat Fragmentation, and Exploitation" (2011). All Graduate Theses and Dissertations. 989. https://digitalcommons.usu.edu/etd/989 This Dissertation is brought to you for free and open access by the Graduate Studies at DigitalCommons@USU. It has been accepted for inclusion in All Graduate Theses and Dissertations by an authorized administrator of DigitalCommons@USU. For more information, please contact [email protected]. ECOLOGY AND CONSERVATION OF COUGARS IN THE EASTERN GREAT BASIN: EFFECTS OF URBANIZATION, HABITAT FRAGMENTATION, AND EXPLOITATION by David C. Stoner A dissertation submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY in Ecology Approved: ______________________ ______________________ Michael L. Wolfe James A. MacMahon Major Professor Committee Member ______________________ ______________________ Johan T. du Toit Frank P. Howe Committee Member Committee Member ______________________ ______________________ Eric Gese Byron Burnham Committee Member Dean of Graduate Studies UTAH STATE UNIVERSITY Logan, Utah 2011 ii Copyright © David C. Stoner 2011 All Rights Reserved iii ABSTRACT Ecology and Conservation of Cougars in the Eastern Great Basin: Effects of Urbanization, Habitat Fragmentation, and Exploitation by David C. Stoner, Doctor of Philosophy Utah State University, 2011 Major Professor: Dr. Michael L. Wolfe Department: Wildland Resources This research was designed to investigate cougar response to urbanization, habitat fragmentation, and exploitation from behavioral, demographic, and landscape perspectives. The source-sink model has been proposed as an alternative framework for the management of exploited cougar populations. I addressed the basic question of whether cougars conform behaviorally to the predictions of the source-sink model, and consequently, the applied question of whether the model could be used for the conservation of this species. To achieve this I evaluated three scale-specific questions using radio-telemetry and hunter-harvest data collected from 1996-2010. At the subpopulation scale, I tested the hypothesis that cougars are wildland obligates by measuring cougar response to a suite of anthropogenic land uses. At the meso scale I compared cougar dispersal patterns from two populations under different management. Lastly, at the statewide scale I examined the distribution of human-induced de facto iv refugia and ecological traps in relation to the species range within Utah. Cougars show a strong proclivity for wildland over rural or suburban habitats, but all cougars used anthropogenic landscapes to some degree, and appear capable of surviving in highly disturbed, human-impacted environments. Cougar dispersal was correlated with maternal estrus; once young animals emigrated, natural and anthropogenic barriers directed movement into habitats marked by frequent human-caused mortality, with females selecting areas of lower conspecific density relative to males. Anthropogenic cougar mortality was disproportionately distributed in accessible, high quality habitats within the core of the species statewide range. Conversely, ecological traps were primarily situated within marginal habitats in remote settings on the periphery of the range. The source-sink model predicts that subordinate animals from saturated populations disperse to habitat with the highest suitability. Cougars of both sexes display behaviors that largely conform to these predictions. Based on the patchy but predictable distribution of cougar exploitation, Utah may already have a quasi source-sink system, which could be formalized through management action. In general, cougars are adaptable, behaviorally plastic, generalist carnivores, and as such defy broad habitat generalizations. These investigations have implications for sustainable hunting and long-term conservation of cougars in the multiple-use landscapes of the Intermountain West. (168 pages) v ACKNOWLEDGMENTS This dissertation is the synthesis of input from the many people I have interacted with over the past decade. A great debt of gratitude goes to my mentor Poopdeck Pappy – is a Renaissance Man born or made? I hope we can continue the discourse in the coming years. Special thanks to my committee, Jim MacMahon, Johan du Toit, Mary Conner, Frank Howe, Mike Jaeger, and Eric Gese, who gave freely of their time and provided excellent advice over the years. Thanks also to the extended committee: Ramona Skirpstunas, Doug Ramsey, Neil West, Tom Edwards, Jim Long, and Larry Hipps. Warm thanks go to my sponsors: from the Utah Division of Wildlife Resources, Kevin Bunnell, Tom Becker, Craig McLaughlin, Alan Clark, Anis Aoude, Heather Bernales, Leslie McFarlane, Kent Hersey, Bill Bates, Boyd Blackwell, Arlo Wing, and Anita Candelaria. From the Utah Army National Guard at Camp Williams, Kennecott Utah Copper, and the Fishlake National Forest I thank Douglas Johnson, Lt. Col. Robert Dunton, Dr. John Crane, Dr. Bill Adams, Ann Neville, and Kreig Rasmussen. The following organizations generously provided subsidiary funding: the Ecology Center at USU, the African Safari Club of Florida, Utah’s Hogle Zoo, The Cougar Fund, American Association of Zoo Keepers, Sportsman’s Warehouse, Cabellas, and the Utah Chapter of the Wildlife Society. First and foremost this has been a field effort, and so I am greatly indebted to my crew in all of its incarnations: Byron Bateman, Greg Jacobson, Tony Kogianes, Lance Redd, Dustin Mitchell, Carey Hendrix, Cristina Juran, Dustin Ranglack, and Kyle Shaney and Meredith Stoner. To the men from God’s Country, Clint and McLain Mecham. I learned more about mountain lions from the back of a horse than I ever did in the library. vi To pilots and friends, Craig Hunt and Clair Shaffer- thanks for the birds-eye perspective. Within the university I had the distinct pleasure of collaborating on many levels with fellow graduate students Wendy Rieth, Sandra Cavalcanti, Debra Carlson, Mike Ebinger, Alex Hernandez, Joe Sexton, and Justin DeRose. Special thanks to Tammy Wilson, Stacey Frisk, and the attendees of the 2010 graduate student Health Fund extravaganza. For statistical wizardry and soothing words extra special thanks to Susan Durham (a.k.a. Glinda, the good witch of the North). To Tom Berry and Michelle Lerwill – thanks for the mirror. Lana Barr, Cecelia Melder, Stephanie White, and Marsha Bailey helped keep the books straight. To Rick Hopson, thanks for providing refuge and a glacial perspective (it’s all relative, n’est pas?). Special thanks to old friends and allies, David Choate, Becky Pierce, Vernon Bleich, Mike Nelson, David Mech, and Lee Aulman. To LL I am glad to have you by my side; to Hailey and Brooke for providing a unique incentive that I never could have mustered without you; and to Mom, Dad, Schniz, and Andy for all the love, support, and patience since the adventure began. Lastly, for their grudging cooperation, I want to thank the Old Hag, the Pole Canyon Tom, the Ketamine Queen, Barney’s runner, Trapfoot, nos. 58a,b and c, the Colorado Queen, the Big Fella, the Hell Bitch, the Greenwich Bitch, the Sundance Kid, and all your brethren; keep to the high ground…. David C. Stoner vii CONTENTS Page ABSTRACT ....................................................................................................................... iii ACKNOWLEDGMENTS .................................................................................................. v LIST OF TABLES ............................................................................................................. ix LIST OF FIGURES ............................................................................................................ x CHAPTER 1. INTRODUCTION AND LITERATURE REVIEW ...................................................... 1 BACKGROUND .......................................................................................................... 1 JUSTIFICATION ......................................................................................................... 5 GOAL AND OBJECTIVES ......................................................................................... 17 2. BEHAVIORAL RESPONSE OF A LARGE, GENERALIST CARNIVORE TO ANTHROPOGENIC LANDSCAPES: FEAR, OPPORTUNITY, OR NONCHALANCE? ..................................................................................................... 29 INTRODUCTION ...................................................................................................... 30 METHODS .............................................................................................................. 34 RESULTS ................................................................................................................ 43 DISCUSSION ........................................................................................................... 47 LITERATURE CITED ................................................................................................ 56 3. DISPERSAL BEHAVIOR OF A POLYGYNOUS