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Coregonus Nigripinnis) in Northern Algonquin Provincial Park

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Coregonus Nigripinnis) in Northern Algonquin Provincial Park HABITAT PREFERENCES AND FEEDING ECOLOGY OF BLACKFIN CISCO (COREGONUS NIGRIPINNIS) IN NORTHERN ALGONQUIN PROVINCIAL PARK A Thesis Submitted to the Committee on Graduate Studies in Partial Fulfillment of the Requirements for the Degree of Master of Science in the Faculty of Arts and Science Trent University Peterborough, Ontario, Canada © Copyright by Allan Henry Miller Bell 2017 Environmental and Life Sciences M.Sc. Graduate Program September 2017 ABSTRACT Depth Distribution and Feeding Structure Differentiation of Blackfin Cisco (Coregonus nigripinnis) In Northern Algonquin Provincial Park Allan Henry Miller Bell Blackfin Cisco (Coregonus nigripinnis), a deepwater cisco species once endemic to the Laurentian Great Lakes, was discovered in Algonquin Provincial Park in four lakes situated within a drainage outflow of glacial Lake Algonquin. Blackfin habitat preference was examined by analyzing which covariates best described their depth distribution using hurdle models in a multi-model approach. Although depth best described their distribution, the nearly isothermal hypolimnion in which Blackfin reside indicated a preference for cold-water habitat. Feeding structure differentiation separated Blackfin from other coregonines, with Blackfin possessing the most numerous (50-66) gill rakers, and, via allometric regression, the longest gill rakers and lower gill arches. Selection for feeding efficiency may be a result of Mysis diluviana affecting planktonic size structure in lakes containing Blackfin Cisco, an effect also discovered in Lake Whitefish (Coregonus clupeaformis). This thesis provides insight into the habitat preferences and feeding ecology of Blackfin and provides a basis for future study. Keywords: Blackfin Cisco, Lake Whitefish, coregonine, Mysis, habitat, feeding ecology, hurdle models, allometric regression, Algonquin Provincial Park ii ACKNOWLEDGEMENTS First and foremost I would like to thank my supervisor Dr. Mark Ridgway for his guidance and support throughout this study. His passion for and knowledge of fisheries science has not only given me inspiration in my pursuits as a graduate student but also in my career. His advice throughout my graduate work and career has helped me greatly. I would also like to thank my committee members, Dr. Michael Fox and Dr. Chris Wilson, who provided guidance and encouragement throughout my graduate studies. I have many people at the Harkness Laboratory of Fisheries Research that I would like to thank for the assistance they have given me during this study. I would like to thank Trevor Middel for his advice and assistance especially during my learning of the programs R and ArcGIS for which I am indebted to him greatly. I would like to thank Gary Ridout, Peggy Darraugh and Lucas Dumas for their help and support during my time at Harkness Lab. Many people assisted in the field aspect particular to this study who I would like to thank including, but not limited to: Nick Lacombe, Sam Luke, Claire Menendez , Krystal Mitchell, Amber Pitawanakwat, Allison Slater, Courtney Taylor, and Derek Van Tol. Many other Harkness staff have been part of the fish community surveys which first discovered these fish, and although too numerous to list here, I would like to thank them for their contributions. I would also like to thank Julie Turgeon and Gabriel Piette-Lauziere from Laval University. Their knowledge on and enthusiasm for Ciscoes made for excellent discussions which broadened my knowledge on all thing Coregonus. I would like to thank fellow graduate students Adam Challice, Ryan Franckowiak, Sarah Poole, and Nicole Paleczny for their advice regarding graduate work. Lastly I would like to thank my family who have provided encouragement and support throughout my graduate work including my Dad, Mom, sister, and especially my wife Heather. iii Table of Contents ABSTRACT ......................................................................................................................................... ii ACKNOWLEDGEMENTS ................................................................................................................... iii Table of Contents .............................................................................................................................iv List of Figures ...................................................................................................................................vi List of Tables ................................................................................................................................... vii CHAPTER 1: General Introduction .................................................................................................... 1 CHAPTER 2: Depth Distribution of Blackfin Cisco. ........................................................................... 7 2.1 INTRODUCTION ..................................................................................................................... 7 2.2 METHODS ............................................................................................................................. 10 2.2.1 Study area ..................................................................................................................... 10 2.2.2 Survey design ................................................................................................................ 11 2.2.3 Covariates...................................................................................................................... 13 2.2.4 Analysis using Hurdle Models ....................................................................................... 15 2.3 RESULTS ................................................................................................................................ 21 2.3.1 Blackfin catch ................................................................................................................ 21 2.3.2 Modelling Blackfin catch ............................................................................................... 23 2.3.3 Covariate effects ........................................................................................................... 23 2.4 DISCUSSION .......................................................................................................................... 34 CHAPTER 3: Feeding Structures ..................................................................................................... 41 3.1 INTRODUCTION .................................................................................................................... 41 3.2 METHODS ............................................................................................................................. 47 3.2.1 Field Methods ............................................................................................................... 47 3.2.2 Laboratory methods ...................................................................................................... 48 3.2.3 Analysis ......................................................................................................................... 49 3.3 RESULTS ................................................................................................................................ 54 3.3.1 Feeding structure meristics ........................................................................................... 54 3.3.2 Feeding structure morphology ..................................................................................... 59 iv 3.4 DISCUSSION .......................................................................................................................... 75 CHAPTER 4: General Discussion of Direction for Future Study ...................................................... 83 LITERATURE CITED ......................................................................................................................... 87 APPENDIX ....................................................................................................................................... 95 v List of Figures Figure 1. Fresh specimen of Blackfin Cisco caught in Radiant Lake, Algonquin Park displaying colouration typical at time of capture. ............................................................................... 2 Figure 2. Digital elevation map of Algonquin Park showing location of Blackfin Lakes (filled black) and Mysis extent (black line). ............................................................................................. 5 Figure 3. Percentage of total netting effort allocated to each stratum (white bars) and percentage of total Blackfin catch in each stratum (black bars) in each study lake with overlaid temperature profile (red). Number of net sets (Nsites) and number of Blackfin caught (Nfish) listed in bottom corner of each plot for each lake. ................................... 22 Figure 4. Predicted Blackfin CPUE based on the depth+depth2 model for Cedar Lake (black line) with 90% confidence limits represented by gray bands. .................................................. 29 Figure 5. Predicted Blackfin CPUE based on the depth+depth2 model for Radiant Lake (black line) with 90% confidence limits represented by gray bands. .................................................. 30 Figure 6. Predicted Blackfin CPUE in Cedar Lake based on the depth+depth2 model with thermocline at the time of sampling represented by a red contour. ............................... 32 Figure 7. Predicted Blackfin CPUE in Radiant Lake
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