Food availability and grizzly bear (Ursus arctos) selection of post-fire and thinned forests in the mountain national parks of Canada by Charles Robert McLellan A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Conservation Biology Department of Renewable Resources University of Alberta © Charles Robert McLellan, 2018 Abstract Human-caused mortality and habitat loss have led to the extirpation of grizzly bears (Ursus arctos) across much of their North American range. Today, these factors continue to limit extant grizzly bear populations as productive habitats often occur in areas with elevated mortality risk creating ecological traps. Maintaining viable grizzly bear populations and preventing further range loss requires minimizing human-caused mortality and maintaining, or enhancing, productive habitats in secure locations. The objectives of this study were to evaluate the effects of post-fire and forest thinning on grizzly bear habitat quality in Banff, Yoho, and Kootenay national parks to assess whether these disturbances enhance grizzly bear habitat. Specifically, I first estimated grizzly bear selection of post-fire habitats across different spatial and temporal scales using data from 26 radio-collared grizzly bears. Factors that influenced grizzly bear selection of burns were then used to predict locations (map) where prescribed burning will most effectively create habitat attractive to bears. Second, I compared the presence and abundance of 25 known grizzly bear foods between burns, thinned forests, and adjacent undisturbed forests testing which factors (climate, terrain, or disturbance) most contributed to their occurrence thus informing future burn or thinning prescriptions. Grizzly bear selection of burns was scale dependant. Burns did not affect home range selection (placement) within the study area but were selected within their home range across the active season (April to November). Compared to thinned or forested areas, burns provided a greater abundance of important early spring, summer, and fall food resources, whereas thinned areas had more abundant green, herbaceous vegetation that is favoured by bears in late spring and early summer. This study provides a more comprehensive understanding of grizzly bear food ii resources and habitat use of burned and thinned areas and supports the use of prescribed fire and thinning for enhancements of grizzly bear habitat in remote, secure areas of the parks. Models from this thesis can assist with planning the locations of future prescribed fires and forest thinning treatments in the region. iii Preface This thesis is an original work by Charles McLellan. Chapter 2 and 3 are intended for publication along with co-authors S.E. Nielsen and J. Park. I contributed to the concept formation, study design, and led work on field data collection, data analysis, and manuscript composition. Scott E. Nielsen and Jane Park contributed to the concept formation, study design, data analysis, and thesis edits. The GPS collar data used for this project was collected by the Parks Canada agency under capture permit number LL-2012-10975. iv Acknowledgements I thank my supervisor, Dr. Scott Nielsen for his support, profound knowledge, and passion for ecological conservation. Scott is a great mentor and he resonates his passion for conservation with everyone who is fortunate enough to work with him. I thank my committee member, Jane Park for her support and mentorship during this research, as well as during other challenging situations we have encountered while working together. I would also like to thank my committee member, Dr. Colleen Cassady St. Clair for her support and commitment to this project, as well as the philosophical conversations that we have shared. Funding for this project was provided by the Joint Action Plan of the Canadian Pacific Railway and Parks Canada. I would like to thank both groups for supporting research that focused on reducing grizzly bear mortality in Banff, Yoho, and Kootenay National Parks. I would also like to thank Parks Canada agency personnel for a successful GPS radio-collaring program. It was these capture efforts that made this research possible. This thesis would not have been possible without the field staff whom hiked or bushwhacked thousands of kilometers to collect data for this project. I will forever look back at those long days, cold creek crossings, and blistered feet with fond memory. Thank you: Kate Johnson, Leah Pengelly, Gavin Hurd, Brigitte Dreger, Tyler Bateman, Andrew Braid, and many others. I would like to thank my parents and sister for their life-long commitment to both grizzly bear research and parenthood. Not a day passes where I don’t cherish my unique childhood and the challenges my parents must have endured. Finally, thank you Alli Banting for all your support along the way. It has been great sharing an office with you. v Table of Contents Abstract ........................................................................................................................................... ii Preface............................................................................................................................................ iv Acknowledgements ..........................................................................................................................v Table of Contents ........................................................................................................................... vi List of Tables ............................................................................................................................... viii List of Figures ................................................................................................................................ ix List of Appendices ........................................................................................................................ xii Chapter 1: General Introduction ......................................................................................................1 1. Literature Cited ....................................................................................................................... 7 Chapter 2: Multi-scale selection of post-fire habitats by grizzly bears in Banff, Yoho, and Kootenay National Parks, Canada .................................................................................................13 1. Introduction ........................................................................................................................... 13 2. Methods ................................................................................................................................. 16 2.1 Study Area ....................................................................................................................... 16 2.2 Landscape mapping and covariate descriptions .............................................................. 17 2.3 Grizzly bear habitat use ................................................................................................... 20 2.4 Multi-scale resource selection and predictive mapping .................................................. 22 3. Results ................................................................................................................................... 25 3.1 Influence of recent burns, older burns, and human-use habitats on grizzly bear home range selection (second-order scale). ..................................................................................... 26 3.2 Seasonal selection of burns, older burns and human-use habitats within home range (third-order scale) .................................................................................................................. 26 3.3 Seasonal within-patch selection of recent burns (fourth-order scale) ............................. 29 4. Discussion ............................................................................................................................. 31 5. Conclusion ............................................................................................................................. 36 6. Literature Cited ..................................................................................................................... 39 Chapter 3: Grizzly bear (Ursus arctos) food production in post-fire and forest-thinned habitats in Banff, Yoho, and Kootenay National Parks, Canada .....................................................................57 1. Introduction ........................................................................................................................... 57 2. Methods ................................................................................................................................. 60 vi 2.1 Study Area ....................................................................................................................... 60 2.2 Grizzly bear foods ........................................................................................................... 61 2.3 Field Sampling ................................................................................................................. 63 2.4 Comparing grizzly bear food occurrence among burns, thinned and control areas ........ 64 2.5 Grizzly bear food productivity ........................................................................................ 65 3. Results ..................................................................................................................................