The abundance and distribution ofbeavers (Castor canadensis) in Québec, Canada Stacey Isabelle Jarema Department ofNatural Resource Sciences McGill University, Montréal August 2006 A thesis subrnitted to McGill University in partial fulfilrnent of the requirernents of the degree of Master of Science © Stacey Isabelle Jarerna 2006 Library and Bibliothèque et 1+1 Archives Canada Archives Canada Published Heritage Direction du Branch Patrimoine de l'édition 395 Wellington Street 395, rue Wellington Ottawa ON K1A ON4 Ottawa ON K1A ON4 Canada Canada Your file Votre référence ISBN: 978-0-494-32724-1 Our file Notre référence ISBN: 978-0-494-32724-1 NOTICE: AVIS: The author has granted a non­ L'auteur a accordé une licence non exclusive exclusive license allowing Library permettant à la Bibliothèque et Archives and Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par télécommunication ou par l'Internet, prêter, telecommunication or on the Internet, distribuer et vendre des thèses partout dans loan, distribute and sell th es es le monde, à des fins commerciales ou autres, worldwide, for commercial or non­ sur support microforme, papier, électronique commercial purposes, in microform, et/ou autres formats. paper, electronic and/or any other formats. The author retains copyright L'auteur conserve la propriété du droit d'auteur ownership and moral rights in et des droits moraux qui protège cette thèse. this thesis. Neither the thesis Ni la thèse ni des extraits substantiels de nor substantial extracts from it celle-ci ne doivent être imprimés ou autrement may be printed or otherwise reproduits sans son autorisation. reproduced without the author's permission. ln compliance with the Canadian Conformément à la loi canadienne Privacy Act some supporting sur la protection de la vie privée, forms may have been removed quelques formulaires secondaires from this thesis. ont été enlevés de cette thèse. While these forms may be included Bien que ces formulaires in the document page count, aient inclus dans la pagination, their removal does not represent il n'y aura aucun contenu manquant. any loss of content from the thesis. ••• Canada ABSTRACT The importance of spatial variation in abundance for the assessment of climate change impacts was examined using the North American beaver (Castor canadensis) in Québec as a model species. A preliminary characterization of the beavers' range edge improved the core-sampling bias and revealed that beavers are present at low densities in shrubby riparian habitats as far north as the communities of Tasiujaq and Umiujaq. Spatial variation in beaver abundance across the province follows a roughly logistic pattern, with abundance peaking in southern Québec, declining steeply around 49°N, and remaining uniformly low as far as 58°N. Although climate sensitivity ofbeaver abundance and the greatest changes in future beaver density are predicted to occur near the middle of their range, beavers are expected to occupy most of the province by 2055. These results highlight the value of incorporating density estimates from across a species' range into climate envelope models. li RÉSUMÉ L'importance de la variation spatiale de l'abondance pour évaluer les conséquences des changements climatiques a été examinée en utilisant le castor nord-américain (Castor canadensis) au Québec comme espèce modèle. Une caractérisation préliminaire des limites de l'aire de répartition des castors a contribué à améliorer le biais d'échantillonnage qui existait en faveur du centre de l'aire et a révélé qu'on retrouve de faibles populations de castors dans des habitats arbustifs aussi loin au Nord que les communautés de Tasiujaq et d'Umiujaq. La variation spatiale de l'abondance des castors à travers toute la province montre une tendance plus ou moins logistique. L'abondance atteint son plus haut niveau dans le sud du Québec, elle diminue sensiblement près du 4ge parallèle nord et elle demeure uniformément basse jusqu'au 58e parallèle nord. Bien qu'on s'attend à ce que la sensibilité des castors aux effets du climat et les plus grands changements à la densité future de leur population aient lieu autour du milieu de leur aire de répartition, il est prévu que les castors habiteront la majeure partie de la province d'ici 2055. Ces résultats soulignent l'importance d'incorporer les estimations de densité de l'aire de répartition au complet d'une espèce dans les modèles d'enveloppe climatique. iü PREFACE Contribution of authors The following thesis is divided into two manuscripts intended for publication (Chapter II and Chapter III). Chapter II presents the results from a preliminary characterization of the beavers' range edge in northern Québec, and is co-authored by Murray M. Humphries and myself. Chapter III, co-authored by Murray M. Humphries, Jason Samson and myself, examines the beavers' abundance pattern across Québec and how the input of such density estimates into species-c1imate envelope models can affect our prediction of c1imate change impacts. Murray M. Humphries, my master's supervisor, was responsible for the initial ideas behind both manuscripts, and provided analytical and editorial guidance throughout the writing process. Jason Samson also provided analytical advice and conducted an important statistical analysis in Chapter III. 1 collected the data (field work and reports), and was responsible for data selection, analysis (e.g., GIS work) , and writing the initial drafts of the manuscripts. For literature citations and formatting, 1 used the guidelines provided by "Arctic" pub li shed by the Arctic Institute of North America, University of Calgary. iv ACKNOWLEDGEMENTS First and foremost 1 would like to thank my supervisor Murray M. Humphries; to whom 1 will always be grateful for taking a chance on me, constantly finding time to discuss my project (even when impossibly busy!), being extraordinarily patient with my MANY questions, helping me with the concepts, analyses and writing of this thesis, and giving me the support and encouragement 1 needed, when 1 needed it most. Next, 1 would like to thank my lab mates (Tricia Kerr, Troy Pretzlaw, Jason Samson), field assistant (Mike Ross) and splendid work-study student (Hsin-Hui Huang). l've been so lucky to have Tricia's warrn support from the very start. She has listened to my worries, understood my frustrations, offered words of encouragement, gave me wonderful advice, and reminded me to take deep breaths through it aH; for this, 1 thank her. Troy and Jason managed to explain modeling and statistical concepts 1 could never have understood from a textbook, and provided awesome feedback whenever 1 asked; for this, 1 thank them. Mike was an awesome field assistant and 1 thank him for his patience, company, and hard work while in Kuujjuaq. Hsin-Hui taught me everything 1 needed to know about GIS and without her, it would have taken me at least another year to finish this project! 1 appreciate aH her hard work and helpful advice. There were also several organizations and people outside McGill that were instrumental in the completion of this thesis: 1 need to thank the Natural Science and Engineering Research Council (i.e., Northem Research Intemship Prograrn and PGS M) for facilitating my stay in Kuujjuaq, subsidizing the costs associated with working in the North and providing financial support during the second year of my masters. 1 am also indebted to the Fonds Québécoise de la Recherche sur la Nature et les Technologies, as weB as Stewart and Anne Brown for providing much needed financial assistance while writing my thesis. A very special thanks goes out to Dr. Bill Doidge (Director, Nunavik Research Centre) and Makivik Corporation for providing logistical support, allowing me to use their facilities, offering important advice and GIS support, giving me the opportunity to volunteer with the CWS, and the li st goes on! Without you guys, it wouldn't have been possible for me to conduct my field work in northem Québec. v Dr. Serge Payette and the Centre d'Études Nordiques were responsible for helping me with my research on the Hudson's Bay coast. 1 wish to extend my most heartfelt thanks and appreciation to Dr. Payette, for supporting me (emotionally, logistically and financially), kindly encouraging me, and inspiring me to be the best researcher 1 can be; he has helped shape the person 1 have become and made my experience in the North something 1 will cherish forever. Thanks to Christian Pilon (Direction du développement de la faune, Société de la faune et des parcs du Québec), René Lafond (Chef d'équipe à la gestion intégrée des ressources, Direction du développement de la faune, Société de la faune et des parcs du Québec), Pierre Canac-Marquis (Coordonnateur Piégeage, Société de la faune et des parcs du Québec) and Hélène Jolicoeur (Direction du développement de la faune, Secteur Faune Québec) for encouraging my research, answering my many questions, and providing me with important results from their beaver research studies conducted in southem Québec. l' d like to send out a huge thanks to Dr. Dan McKenney and Pia Papadopol (Great Lakes Forestry Centre, Natural Resources Canada, Govemment of Canada) for providing me with the selected modeled c1imate data for point locations, and answering my sometimes arduous requests! Last, but definitely not least, 1 must thank my family and friends for there incredible support and encouragement from the very beginning. Most importantly, 1 have to thank my wonderful husband and my beautiful mom for their unconditional love, patience, and faith in me. As a small token of my love for them, and of my gratitude for all that they have sacrificed for me, 1 dedicate this thesis to them. vi TABLE OF CONTENTS ABSTRACT ........................................................................................................................ ii RÉSUMÉ ........................................................................................................................... iii PREFACE .........................................................................................................................