THE IMPLICATIONS OF LAKE HISTORY FOR CONSERVATION BIOLOGY Kristine Alexia Ciruna A thesis submitted in conformity with the requirements for the degree of Doctor of Philosophy Graduate Department of Zoology, University of Toronto O Copyright by Kristine Alexia Cinina 1999 National Libraiy Biiiotheque nationale du Canada Acquisitions and Acquisitions et Bibliographie Services sewices bibliographiques 395 Wellmgtori Street 395, nie WeJMngton OüawaON K1A ON4 OitawaON K1AW Canada CaMda The author has gmnted a non- L'auteur a accordé une licence non exclusive licence allowing the exclusive permettant à la National Library of Canada to Bibliothèque nationale du Canada de reproduce, loan, distribute or selî reproduire, prêter, distribuer ou copies of this thesis in microform, vendre des copies de cette thèse sous paper or electronic formats. la forme de microfiche/nlm, de reproduction sur papier ou sur fomiat électronique. The author retains ownershp of the L'auteur consme la propriété du copyright in this thesis. Neither the &oit d'auteur qui protège cette thèse. thesis nor substantial extracts fkom it Ni la thèse ni des extraits substantiels may be printed or otherwise de celle-ci ne doivent être imprimés reproduced without the author's ou autrement reproduits sans son permission. autorisation. Abstract ABSTRACT Ciruna, Kristine Alexia. 1999. The implications of lake history for conservation biology. Ph.D. dissertation. Department of Zoology, University of Toronto, Toronto, Ontario. The historical formation of aquatic ecosystems and the regional environmental processes acting at the watershed level are important components in the conservation of aquatic ecosystems which are often'neglected. This thesis integrates the fields of cornmunity and landscape ecology. conservation biology, multivariate statistics and geographical information processing in an attempt to examine the ecology of fish communities within 550 inland lakes in the Great Lakes - St. Lawrence basin of Ontario with respect to their local and regional environment and historical lake formation. These lakes have been grouped into six geographic regions: Wellington, Bruce Peninsula, Lacloche, Sudbury, Wawa, and Algoma. Two new constructs have been created which describe lakes based on their historical formation: "relict" and "solus". A relict lake is defined as a lake that was once part of a large waterbody presumably sharing a common species pool that has since receded to form a number of smaller lakes. A solus lake is defined as a lake formed in isolation which was never a part of a larger water system or species pool. Differences in fish community structure, environment, and species - environment relationships were examined between proximally paired relict and solus lake regions using a suite of rnultivariate statistics. The results of this study conclude that relict and solus lakes have significantly different local and regional environments, fish comrnunity structure, and species - environment retationships. Striking similarities were also found Abstract between relict and solus lakes and landbridge and oceanic islands, respectively, regarding historical formation, extinction and colonization potential, and comrnunity structure. The results strongly suggest that solus lakes and their surrounding watersheds represent ecologically distinct aquatic systems within Ontario containing unique environments and fish species assemblages. Recommendations are made for the inclusion of solus lake regions as provincial "Areas of Natural and Scientific Interest". Therefore the recognition of lakes as historical constructs which 1 term relict and solus provides insight into conservation planning for fish biodiversity. Acknowledaements ACKNOWLEDGEMENTS I am very grateful to have had the opportunity to doing my graduate studies at the Department of Zoology, University of Toronto. This institution has provided me with an academic program that helped stimulate my intellectual growth and a scientific community which encouraged me to develop new ideas. First and foremost I would like to thank Professor Harold H. Harvey, my supen/isor, for his ünending encouragement and guidance in the development of the ideas and concepts contained in this thesis. It is an honour to have been mentored by such an outstanding scientist. 1 would also like to thank Professors Ann Zimmerman, Jyri Paloheimo, and Ed Crossman for their helpful discussions pertaining to the species and environment analyses used in this thesis, their ongoing support and their great sense of humour. I thank the following individuals for providing sorne of the data and tools used in this thesis: Professor Larry Band, Department of Geography, University of Toronto; Professor Terry Carleton, Faculty of Forestry. University of Toronto: Mr. George Gale, Ontario Ministry of Natural Resources; and Mr. Erling Holm, Centre for Biodiversity and Conservation, Royal Ontario Museum. I am grateful to al1 those at U of T who directly or indirectly have given me the benefit of their experience. Especially, I want to thank al1 of my rnany friends in the Dept. of Zoology for al1 of the great times and memories. 1 am very fortunate to have such great friends! Most of all, I want to thank rny parents lrene and John and my brother Brian who supported me throughout my academic career. 1 could not have done it without your help. Kristine A. Ciruna Table of Contents p. TABLE OF CONTENTS Page ABSTRACT ............................................................................................ ii ACKNOWLEDGMENTS .......................................................................... iv LIST OF TABLES ................................................................................... xii LISTOFFIGURES ................................................................................. xvii CHAPTER 1 THESIS INTRODUCTION ................................................... 1-1 I. OVERVIEW OF FRESHWATER ECOSYSTEM CONSERVATION IN CANADA ...................................................................................... A . Water Resources ...................................................................... B . Canadian Freshwater Fishes in Peril............................................ C . Dichotomy of Consewation......................................................... D. Causes for Decline of Freshwater Fishes ...................................... E. Needed Research and Consewation Management........................ II. THIS STUDY: A STEP IN THE RlGHT DIRECTION.............................. A . Objectives ............................................................................... 1. Chapter Two ....................................................................... 2 . C hapter Three ..................................................................... 3 . Chapter Four ....................................................................... 4 . Chapter Five ....................................................................... 5 . Chapter Six ......................................................................... CHAPTER 2 RELICT AND SOLUS LAKES ................................................ 2-1 1. INTRODUCTION............................................................................ 2-1 A . Definition of Relict and Solus Lakes.............................................. 2-1 II. Relict and Solus Lakes Throughout the World ..................................... 2-2 III. Glacial Solus Lakes Within the Great Lakes - St. Lawrence Basin........... 24 IV. Glacial Relict Lakes Within the Great Lakes - St. Lawrence Basin ........... 2-6 V . Evidence for the Formation of Glacial Relict and Glacial Solus Lakes..... 2-7 Table of Contents Page V . Evidence for the Formation of Glacial Relict and Glacial Solus Lakes ..... 2-7 VI . CONCLUSIONS........................................................................ 2-8 CHAPTER 3 AN EXAMINATION OF ENVIRONMENTAL DIFFERENCES IN RELICT AND SOLUS LAKES WITHIN THE GREAT LAKES . ST . LAWRENCE BASIN ....................................................... 3-1 INTRODUCTION............................................................................. 3-1 A Objectives of This Chapter ........................................................... 3-2 1. Defining Environmental Variables ............................................ 3-2 a) Ecological Boundaries...................................................... 3-2 b) Local and Regional Environmental Variables ......................... 3-2 c) Relationships Between Local and Regional Environmental Variables ....................................................................... 34 MATERIALS AND METHODS ........................................................... 3-6 A Study Lakes ............................................................................ 3-6 I . Databases...................................................................... 3-6 B Study Variables ......................................................................... 3-8 1. Local Environmental Variables .......................................... 3-9 2 . Regional Environmental Variables .......................................... 3-12 C Statistical Methods .................................................................... 3-15 1. Normality. Linearity and Transformation of Environmental Variables ............................................................................ 3-15 2. Wilcoxon-Mann-Whitney Test ................................................. 3-15 3 . Canonical Correlation Analysis ..............................................