University of Alberta a Re-Examination of the Nominal
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University of Alberta A Re-examination of the Nominal Shortjaw Cisco (Coregonus zenifhicus) in Barrow Lake, Aiberta and Taxonornic Evaluation of Neighbo~gCisco Populations Mark Steinhilber O A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Systematics and Evolution Department of Biological Sciences Edmonton, Alberta Fa112000 National Library Bibliothèque nationale lei ,.a",, du Canada Acquisitions and Acquisitions et Bibliographie Services services bibliographiques 395 Wellington Street 395, rue Wellington Ottawa ON KIA ON4 Ottawa ON K1A ON4 Canada Canada Your file Vowe r6lëmw Our fiie Ncrre réUrence The author has granted 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 sell reproduire, prêter, distribuer ou copies ofthis 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 format électronique. The author retains ownership of the L'auteur conserve la propriété du copyright in this thesis. Neither the droit d'auteur qui protège cette thèse. thesis nor substantial extracts fÎom 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 The morphology, ecology, and genetics of the putative Coregonus zenithicus (shortjaw cisco) in Barrow Lake, Alberta were exarnined to venfy the distinctiveness and specific identity of this population. Ciscoes from five nearby Mes provided comparative specimens for assessrnent of local variation, and sarnples of known C. zenithicus from eight lakes across North Arnenca were used to assist in identification. Of the six Alberta lakes sampled, four contâined syrnpatric cisco populations. Sympatric forrns in Ryan Lake and Unnamed Lake were believed to be C. artedi (lake cisco) in different stages of divergence. One forrn of the sympatric pair in Bocquene Lake may represent C. sardinella (least cisco). The low gillraker cisco in Barrow Lake conformed morphoIogically to C. zenithicus. Despite minor differences, the Barrow Lake C. zenithicus overlapped completely in principal component plots with known C. zenithicrts populations. Mitochondrial DNA d-loop sequence analysis was inconclusive but consistent with other studies examining genetic variation between C. zenithicus and C. artedi. The morphological and ecological data do not support an hypothesis of sympatric speciation. A scenario of secondary, post-Pleistocene contact between C. zenithicus and C. artedi in this lake is favoured. Acknowledgments I would like to thank my supervisor, Dr. Joseph. S. Nelson for his support, encourage- ment, and guidance during this study. 1 am especially grateful for the freedom to deter- mine the goals and direction of the projectand for the patience and understanding he demonstrated with respect to my other commitments. Thank you also to the other mem- bers of my supervisory cornmittee, Dr. Mark V. H. Wilson, Dr. Bill Tonn, and Dr. James Reist, for their advice and support. In addition to overall critiques of the study, Dr. Reist provided valuable information on coregonine taxonomy and statistical analyses. His active participation in this project, despite the logistic difficulty and expense of travel- ling from Winnipeg to Edmonton for supervisory meetings, is greatly appreciated. I am indebted to Dr. Philip H. R. Stepney, Director of the Provincial Museum of Alberta and Dr. W. Bruce McGillivray, Assistant Director, Curatorial and Collections Management, ProvinciaI Museum of Alberta for allowing me to pursue this project. Dr. McGillivray not only provided encouragement but also welcome advice on statistical procedures and systematics in general. This project would not have been possible without the technical assistance of Stephen Peterson and Matthew Thompson who worked long hours under difficult conditions to assist in the acquisition of specimens. 1 also thank Lianne Maiers of the Freshwater Institute, Department of Fisheries and Oceans Canada in Winnipeg for conducting the rnitochondrial DNA analysis of cisco samples from Barrow Lake. Dr. Gertie Hutchinson of the limnology laboratory at the University of Alberta (now retired) provided the equipment. analyses, and much needed advice for the gathering of water chemistry data. Wayne Roberts of the University of Alberta Museum of ZooIogy kindly provided access to museum specimens and collecting equipment and training in x-ray procedures. Finally, 1 thank rny wife, CoIleen, and children, Mandi and Matthew, for the sacrifices they have had to make over the pst few years. This research was supported in part by the Challenge Grants in Biodiversity Program, Department of Biologicai Sciences, University of Alberta, and the Alberta Conservation Association and in part by the Northem Scientific Training Program of the Department of Indian and Northem Affairs, Canadian Circumboreal Institute, University of Alberta. Additional field, laboratory, and clerical support was provided by the Provincial Museum of Alberta. Table of Contents Introduction .....................................................1 The Question .............................................. -1 Objective .................................................. 2 TheCoregoninae ............................................ 3 Species Concepts ........................................... -5 Species Definitions ......................................... 10 Morphological Markers of Coregonus artedi and C. zenirhicus Populations .................................... -13 Methods ...................................................... 25 StudyArea ............................................... 25 Specimen Acqiiisition ...................................... -30 Morphometrics and Meristics ..................................31 Character Independence and Redundancy ....................... -34 Statistical Analyses ........................................ -36 Ageing of Specimens ........................................43 Stomach Content Analysis ................................... -43 Environmental Data ......................................... 44 Genetic Analysis .......................................... -44 Results ...................................................... 45 Cornparison of Barrow Lake Ciscoes ........................... -45 Specific Identity of the Bmow Lake Low Gillraker Cisco ............60 Other Sympatric Alberta Cisco Populations .......................69 RyanLake ................................................ 69 BocqueneLake ............................................81 UnnamedLake ............................................ 90 Morphologicai Overvietv of al1 Northeastern Alberta Cisco Populations Examined . Discussion . Factors Confounding the Interpretation of Morphological Data . -103 The Origins of Sympatric Species . -116 Genetics of Barrow Lake Ciscoes . .129 Postglacial Dispersai and Zoogeography of C. zenithicus and C. artedi -133 Taxonomic Summary of Sympatric Northeastern Alberta Ciscoes . .137 Literature Cited . -139 List of Tables Table 1. Selected references and characters used in historical descriptions of C. artedi and C. zenithicus (and synonyms) ..................... 22 Table 2. Lake basin morphometry of the six lakes surveyed in this study ...... -28 Table 3. Water chemistry of the six lakes surveyed in this study ............. .29 Table 4. Efficacy of size removal using regression residual transformation .....-41 Table 5- Parameters of Barrow Lake cisco morphometnc data .............. -48 Table 6. Inter-population comparison of Barrow Lake cisco morphometrics andmeristics ............................................... 50 Table 7. Summary of sexual dimorphism in Barrow Lake ciscoes ............ -52 Table 8. Eigenvalues and eigenvectors of the first two principal components based on 13 morphometric characters from Barrow Lake ciscoes ...................................................- -54 Table 9. Variable positions in a 321 bp. segment of the mitochondrial DNA d-loop from C. artedi and C zenirhicus specimens examined in this study and by Bodaly et al. (1998), Reist et al. (1998), and Reed et al. (1998) ....-55 Table 10. Eigenvalues and eigenvectors from the principal components 2 and 3 based on 19 morphometric characters from al1 Alberta ciscoes exarnined ........................................... -6 1 Table 11. Cornparison of the holotypes of L macrognathus, L. athabascae, and L. entomophagus (Harper and Nichols 19 19) with known C. zenithicus and C. artedi. ................................... .63 Table 12. Meristic cornparison of C. zenithicus and C. artedi populations ......-65 Table 13. Eigenvdues and eigenvectors of the first three principal components based on six morphometric characters from al1 C. zenithicus and C. artedi populations ........................................ -72 Table 14. Parameters of Ryan Lake cisco morphometric data. ............... -74 Table 15. Inter-population comparison of Ryan Lake cisco morphometrics and meristics .............................................. -75 Table 16. Surnmary of sexual dimorphism in Ryan Lake high gillraker ciscoes . -77 Table 17. Eigenvalues and eigenvectors from the first two principal components based on 18 morphometric characters frorn