The Olympic Marmot
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University of Montana ScholarWorks at University of Montana Graduate Student Theses, Dissertations, & Professional Papers Graduate School 2008 Demography and ecology of a declining endemic: The Olympic marmot Suzanne Cox Griffin The University of Montana Follow this and additional works at: https://scholarworks.umt.edu/etd Let us know how access to this document benefits ou.y Recommended Citation Griffin, Suzanne x,Co "Demography and ecology of a declining endemic: The Olympic marmot" (2008). Graduate Student Theses, Dissertations, & Professional Papers. 299. https://scholarworks.umt.edu/etd/299 This Dissertation is brought to you for free and open access by the Graduate School at ScholarWorks at University of Montana. It has been accepted for inclusion in Graduate Student Theses, Dissertations, & Professional Papers by an authorized administrator of ScholarWorks at University of Montana. For more information, please contact [email protected]. DEMOGRAPHY AND ECOLOGY OF A DECLINING ENDEMIC: THE OLYMPIC MARMOT. By Suzanne Cox Griffin Bachelor of Arts, University of Montana, Missoula, MT 2001 Dissertation presented in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Fish and Wildlife Biology The University of Montana Missoula, MT Autumn 2007 Approved by: Dr. David A. Strobel, Dean Graduate School L. Scott Mills, Co-Chair Department of Ecosystem and Conservation Sciences Mark L. Taper, Co-Chair Department of Ecology, Montana State University Fred W. Allendorf Division of Biological Sciences Elizabeth Crone Department of Ecosystem and Conservation Sciences David Naugle Department of Ecosystem and Conservation Sciences Dirk H. Van Vuren Department of Wildlife, Fish, and Conservation, UC Davis © COPYRIGHT by Suzanne Cox Griffin 2007 All Rights Reserved Griffin, Suzanne C., Ph.D., December 2007 Fish and Wildlife Biology Demography and ecology of a declining endemic: The Olympic marmot. Co-Chairperson: L. Scott Mills Co-Chairperson: Mark L. Taper Protected areas serve to conserve species, habitats, and ecological processes. However, biological systems within even large parks are increasingly affected by outside perturbations. The Olympic marmots (Marmota olympus) are ground-dwelling squirrel that inhabit high-elevation meadows almost exclusively within Olympic National Park Despite this protection, anecdotal reports in the 1990’s of disappearances from historically occupied locations suggested that the species was in decline. I used demographic monitoring, habitat surveys, and non-invasive genetic sampling to evaluate population status of the species and consider the effects of several possible stressors. Olympic marmots disappeared from ~50% of well-studied colonies, and abandoned burrow complexes were common throughout the park. Estimated annual abundances at intensively studied sites indicated a currently declining population, as did population projections based on measured demographic rates. Low dispersal rates and the spatial distribution of the abandoned sites were inconsistent with metapopulation dynamics as the cause of the declines. There was no evidence that disturbance by tourists was responsible – although marmot behavior differed between remote and regularly-visited sites, there was no corresponding difference in birth or death rates. Likewise, 100% overwinter survival of adults and normal reproductive and juvenile survival rates provide no support for the hypothesis that changes in forage quality or thermal conditions within hibernacula associated with low snowpack were causing the decline. In fact, consecutive year breeding by females during years of early snowmelt suggest a possible positive effect of climate warming. Adult female annual survival was only 0.69, all mortality appeared to be due to predation with coyotes the most common predator, and even moderate changes in adult female mortality rates translated to large changes in projected population growth rates, so it is likely that coyotes are the primary driver of local Olympic marmot declines. Given that marmot populations appear depressed throughout Olympic National Park and that marmots constitute a considerable portion of coyotes diet in many parts of the park (Witczuk 2007), it is likely that this non-native, generalist carnivore is threatening the marmot’s existence throughout its range. As parks become increasingly isolated and surrounded by human perturbations, it will be ever more important to monitor species of special interest within these areas; and when a threat is suspected, to consider more than just the most obvious candidates. iii Dedication To my husband Paul, whose endless patience, encouragement, and sacrifice made this possible To my children Orion and Alpine, with the hope that a little piece of the wild will remain when you are grown And to the high-country everywhere, and those that make it their home – your beauty, strength, and endurance are my greatest inspirations iv ACKNOWLEDGEMENTS The National Science Foundation (DEB-0415604, DEB-0415932), Mazama, Northwest Scientific Association, American Society of Mammalogists, American Museum of Natural History, Anheuser-Busch Corporation and the National Fish and Wildlife Foundation (through a Budweiser Conservation Scholarship), a US EPA Graduate Student Fellowship, an NSF Graduate Student Fellowship, The Canon National Parks Science Scholars Program, and the UM College of Forestry and Conservation provided funding and support. I owe much to my committee and other academic colleagues. Scott Mills and Mark Taper allowed me to pursue my dream of studying marmots – they took me on as a joint student, connected me with the park, and helped me obtain funding. They and the rest of my committee – Fred Allendorf, Elizabeth Crone, Dave Naugle and Dirk VanVuren – challenged me, encouraged me, and reined me in when necessary. Dirk provided valuable insights into marmots and, most importantly, has been a wonderful mentor. Ken Armitage and Andrew Bryant were also generous with their vast knowledge of marmots and each found time to critique my work. John Citta, Steve Hoekman, Brett Walker, and the Mills’ lab provided valuable feedback and intellectual stimulus. Dan Pletcher listened when I needed an ear and encouraged me when I needed a push. Pat Bristol, Patti Loewen, and Jodi Todd held my hand through the morass of regulations and paperwork associated with a large project with many funding sources. Their patience and competence made this possible. Similarly, Jeanne Franz guided me through the graduate school and university requirements, rescued me from many crises, and provided me with too many treats. v The Vancouver Island Marmot Recovery Foundation contributed Dr. Malcolm McCadie’s time and veterinary expertise. Malcolm himself put in 18-hour days, packed heavy equipment many miles, necropsied marmots at midnight, and answered thousands of questions, all the while insisting that he was on holiday. The interest that Don Doyle and the Vancouver Island Marmot Recovery Team expressed in Olympic marmot ecology encouraged me to go on when my confidence was low. Dozens of wonderful people worked extremely hard in the field, many as volunteers. In particular, Stan Pagacz, Julia Witczuk, Kevin Sterling, and Alex Powell put in multiple years – Stan and Kevin surveyed places no sane person would have gone, Stan and Alex each served as crew supervisor at least one year, and Julia kept me organized for two years before she delved into an M.S. project of her own. I thank Kristy Pilgrim, Reesa Yale, Jason Hicks, Stan Pagacz, and especially Steve Amish for their work in the genetics lab. Numerous Olympic National Park staff helped along the way – Patti Happe, Cat Hoffman, and Jerry Freilich granted permission for a small army to invade the park, Roger Hoffman provided critical GIS assistance, Janis Burger shared her considerable knowledge of the park in general and marmots in particular, and many rangers, education, and campground staff arranged prime campsites, let us through gates, gave us rides, shared their food, and reported marmot sightings. Most of all, I thank my family. My husband Paul has been steadfast in his support and encouragement. He contributed in too many ways to list and I cannot thank him enough. My father, Archibald Cox, has supported me every way he could – beginning with a hair-raising drive through a blizzard to get me to Montana. My in-laws John and Christena Griffin provided encouragement from the perspective of family members / vi scientists-in-a-different-field. My son Orion assisted with field work and provided a perspective that only a small child can. Most recently, little Alpine, age 10 weeks as of this writing, slept all night, every night. And many years ago, my mother let me play in the woods and taught me to love animals – although I don’t think she had giant rodents in mind! vii PREFACE A primary driver of extinctions, particularly in North America where hunting is strictly controlled, is habitat loss or degradation (Wilcove et al. 1998). Thus, parks and other protected areas serve an important role in conserving species, habitats and ecological processes. However, even the largest parks do not operate in isolation from the human dominated landscapes outside their borders. As external ecosystems become increasingly disturbed, the climate continues to change, non-indigenous species encroach upon protected areas, and recreational use of wildlands increases, parks will be faced with difficult management decisions. When I began studying Olympic