Movement and Habitat Use of Lake Sturgeon (Acipenser Fulvescens) in the South Saskatchewan River System
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CORE Metadata, citation and similar papers at core.ac.uk Provided by OPUS: Open Uleth Scholarship - University of Lethbridge Research Repository University of Lethbridge Research Repository OPUS http://opus.uleth.ca Theses Arts and Science, Faculty of 2013 Movement and habitat use of lake sturgeon (Acipenser fulvescens) in the South Saskatchewan River system Lacho, Christine D. Lethbridge, Alta. : University of Lethbridge, Dept. of Biological Sciences http://hdl.handle.net/10133/3570 Downloaded from University of Lethbridge Research Repository, OPUS MOVEMENT AND HABITAT USE OF LAKE STURGEON (ACIPENSER FULVESCENS) IN THE SOUTH SASKATCHEWAN RIVER SYSTEM CHRISTINE D. LACHO Bachelor of Science, University of Winnipeg, 2009 A Thesis Submitted to the School of Graduate Studies of the University of Lethbridge in Partial Fulfillment of the Requirements for the Degree MASTER OF SCIENCE Department of Biological Sciences University of Lethbridge LETHBRIDGE, ALBERTA, CANADA © Christine D. Lacho, 2013 ABSTRACT Lake Sturgeon (Acipenser fulvescens) have experienced declines in numbers throughout their range due to historical overharvesting and more recent habitat degradation. Fragmentation and disruption caused by large dams on the rivers they inhabit have greatly impacted this species. Lake Sturgeon in Alberta are part of an Endangered population as defined by the Committee on the Status of Endangered Wildlife in Canada. The goal of this study was to gather more information on the movement of Lake Sturgeon in the South Saskatchewan River in Alberta and Saskatchewan, to aid conservation. A sample of 123 Lake Sturgeon was tracked in this area for 24.5 months using hydroacoustic telemetry, and a habitat survey gathered depth and substrate data for the study area. Lake Sturgeon had large ranges of movement, and individuals moved the second-highest range on record for this species. Movement varied by season, and adult Lake Sturgeon moved at higher rates and used greater reaches of the river than juveniles. Two possible spawning sites and three overwintering sites were identified, areas which should be left undisturbed by development. The large extent of movement observed in the study area emphasizes the need to leave the South Saskatchewan River system relatively unrestricted by dams and weirs, as blocking movement may have negative impacts on this population of Lake Sturgeon. ii ACKNOWLEDGEMENTS I would first like to thank my advisor, Dr. Joe Rasmussen, for his help and guidance. I would also like to thank my committee members: Dr. Andy Hurly, Dr. Dan Johnson, Terry Clayton (Alberta Environment and Sustainable Resources), and Shane Petry (Alberta Environment and Sustainable Resources) for their time and assistance. Doug Watkinson (Fisheries and Oceans Canada) is also thanked for all his assistance with field work and data analysis, and for his helpful feedback. Emeric Janssens, Eztiaan Groenewald, and Trevor Semchuck are gratefully thanked for all their hard work and long days spent in the field. I would also like to thank Meghan Carr from the University of Saskatchewan for spending long days in a boat with me collecting habitat data and for analyzing the data from the survey. In addition, many volunteers assisted with capturing and tagging lake sturgeon during the project and I am grateful for all their help. Cam Barth and Lee Murray from North-South Consultants, Inc. provided valuable field assistance and training during the start-up of the project. Thanks to Andreas Luek and Astrid Schwalb for their assistance and helpful feedback. Funding and in-kind support for this project were provided by Fisheries and Oceans Canada and Alberta Environment and Sustainable Resource Development. Funding was also provided from the Canadian Wildlife Federation Endangered Species Fund and a Canada Graduate Scholarship from the Natural Sciences and Engineering Research Council of Canada. I can’t neglect to thank all my friends and family for their support during this time. I’d like to thank the other members of the Rasmussen and Hontela labs and the other biology grad students who formed a tight group to commiserate and relax during our Friday night pub nights. And finally, thanks to Stephen, who moved to Alberta, kept iii me sane, and even made maps for me. Your support kept me going throughout this whole process. iv TABLE OF CONTENTS ABSTRACT ........................................................................................................................ II ACKNOWLEDGEMENTS ...............................................................................................III TABLE OF CONTENTS .................................................................................................... V LIST OF TABLES ........................................................................................................... VII LIST OF FIGURES ........................................................................................................ VIII LIST OF ABBREVIATIONS ............................................................................................. X CHAPTER ONE: INTRODUCTION ..................................................................................1 Lake Sturgeon Background and Life History ..................................................................1 Threats to Lake Sturgeon .................................................................................................3 Lake Sturgeon in Alberta .................................................................................................7 South Saskatchewan River Basin ....................................................................................9 Thesis Project .................................................................................................................10 CHAPTER TWO: MOVEMENT AND HABITAT USE OF LAKE STURGEON IN THE SOUTH SASKATCHEWAN RIVER SYSTEM.............................................12 Abstract ..........................................................................................................................12 Introduction ....................................................................................................................13 Methods .........................................................................................................................15 Study Area ................................................................................................................15 Acoustic Tagging ......................................................................................................16 Acoustic Receivers ...................................................................................................18 Habitat Assessment ..................................................................................................20 Data Analysis ............................................................................................................23 Results ............................................................................................................................26 Distribution ...............................................................................................................27 South Saskatchewan River .................................................................................27 Oldman River .....................................................................................................28 Bow River ..........................................................................................................28 Red Deer River ..................................................................................................29 Influence of Maturity Level ......................................................................................29 Seasonal Movement Patterns ....................................................................................30 Abiotic Factors .........................................................................................................32 Habitat Analysis .......................................................................................................33 Overwintering Locations ..........................................................................................34 Discussion ......................................................................................................................35 Distribution ...............................................................................................................35 South Saskatchewan River .................................................................................36 v Oldman River .....................................................................................................37 Bow River ..........................................................................................................38 Red Deer River ..................................................................................................38 Influence of Maturity ................................................................................................39 Seasonal Patterns ......................................................................................................40 Diel Movement Patterns ...........................................................................................41 Effect of Abiotic Factors ..........................................................................................42 Overwintering Locations / Core Habitat Areas ........................................................42