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Shortjaw Cisco (Coregonus Zenithicus) in Alberta

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Shortjaw Cisco (Coregonus Zenithicus) in Alberta Status of the Shortjaw Cisco (Coregonus zenithicus) in Alberta Mark Steinhilber Alberta Wildlife Status Report No. 41 March 2002 Published By: i Publication No. T/014 ISBN: 0-7785-1983-X (Printed Edition) ISBN: 0-7785-1984-8 (On-line Edition) ISSN: 1206-4912 (Printed Edition) ISSN: 1499-4682 (On-line Edition) Series Editors: Sherry Feser and Robin Gutsell Illustrations: Brian Huffman For copies of this report, contact: Information Centre - Publications Alberta Environment/Alberta Sustainable Resource Development Fish and Wildlife Division Main Floor, Great West Life Building 9920 - 108 Street Edmonton, Alberta, Canada T5K 2M4 Telephone: (780) 422-2079 OR Information Service Alberta Environment/Alberta Sustainable Resource Development #100, 3115 - 12 Street NE Calgary, Alberta, Canada T2E 7J2 Telephone: (780) 297-3362 OR Visit our web site at : http://www3.gov.ab.ca/srd/fw/status/index.html This publication may be cited as: Steinhilber, M. 2002. Status of the Shortjaw Cisco (Coregonus zenithicus) in Alberta. Alberta Sustainable Resource Development, Fish and Wildlife Division, and Alberta Conservation Association, Wildlife Status Report No. 41, Edmonton, AB. 23 pp. ii PREFACE Every five years, the Fish and Wildlife Division of Alberta Sustainable Resource Development reviews the status of wildlife species in Alberta. These overviews, which have been conducted in 1991, 1996 and 2000, assign individual species “ranks” that reflect the perceived level of risk to populations that occur in the province. Such designations are determined from extensive consultations with professional and amateur biologists, and from a variety of readily available sources of population data. A primary objective of these reviews is to identify species that may be considered for more detailed status determinations. The Alberta Wildlife Status Report Series is an extension of the general statusing exercises (1996 Status of Alberta Wildlife, The General Status of Alberta Wild Species 2000), and provides comprehensive current summaries of the biological status of selected wildlife species in Alberta. Priority is given to species that are potentially at risk in the province (“At Risk,” “May Be At Risk”), that are of uncertain status (“Undetermined”), or those considered to be at risk at a national level by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC). Reports in this series are published and distributed by the Alberta Conservation Association and the Fish and Wildlife Division of Alberta Sustainable Resource Development. They are intended to provide detailed and up-to-date information which will be useful to resource professionals for managing populations of species and their habitats in the province. The reports are also designed to provide current information which will assist the Alberta Endangered Species Conservation Committee to identify species that may be formally designated as “Endangered” or “Threatened” under Alberta’s Wildlife Act. To achieve these goals, the reports have been authored and/or reviewed by individuals with unique local expertise in the biology and management of each species. iii EXECUTIVE SUMMARY The shortjaw cisco is currently designated “Threatened” by the Committee on the Status of Endangered Wildlife in Canada (COSEWIC) as a result of overexploitation and habitat degradation in the Great Lakes. It is currently ranked “May Be At Risk” in Alberta. This ranking is based on status definitions outlined in The General Status of Alberta Wild Species 2000 (Alberta Sustainable Resource Development 2001). This report reviews and summarizes recent and historical information on the shortjaw cisco as a step in further assessing its status in Alberta. The only verified report of shortjaw cisco in Alberta is from Barrow Lake in the Canadian Shield region of the province. Reports from two other sites, Lake Athabasca and Gregoire Lake southeast of Fort McMurray, are questionable. The taxonomy, ecology, and distribution of shortjaw cisco in northeastern Alberta are currently being re-examined. Results to date suggest the Barrow Lake population resembles known shortjaw cisco morphologically and genetically. Ecologically, this population differs from “typical” shortjaw cisco populations in that it occupies shallow water habitats. Feeding and reproduction appear to be similar to populations at other localities. Preliminary catch-per-unit-effort data suggest the population in Barrow Lake is stable, although more data are required to estimate absolute population size and to assess sampling variance and the predictive power of abundance trends. Surveys of 18 lakes in the area around Barrow Lake from 1996 to 2001 failed to locate any additional populations of this species. Samples from Cold Lake–the site of an unverified historical report of shortjaw cisco–were also analyzed and determined to represent lake herring. Voucher specimens of cisco from all fisheries inventory projects in northern Alberta should be examined carefully and deposited in a museum for future analysis. The factors that have caused the decline in shortjaw cisco populations in the Great Lakes (commercial overfishing, habitat degradation, competition with introduced species, and sea lamprey predation) are currently of little consequence to Alberta shortjaw cisco. Natural factors such as competition and introgression with sympatric lake herring may pose the greatest risk to the persistence of this species in the province. Anthropogenic factors that may upset the delicate ecological balance in Barrow Lake, and any other lakes in which shortjaw cisco may eventually be found, should be considered carefully in future management strategies. iv ACKNOWLEDGEMENTS Thanks to Thomas Todd of the Great Lakes Science Center for providing information on shortjaw cisco in the Great Lakes area and for supplying a draft of his COSEWIC report currently in preparation. Wayne Roberts (University of Alberta Museum of Zoology) and Erling Holm (Royal Ontario Museum) facilitated access to specimens housed in these institutions. Darlene Balkwill and Sylvie Laframboise (Canadian Museum of Nature) and Dr. William Preston (Manitoba Museum of Man and Nature) kindly supplied data on shortjaw cisco holdings in their collections. Larry Rhude (Alberta Sustainable Resource Development, Fisheries Management) provided information dealing with the management of shortjaw cisco in Alberta. Wes English (Alberta Sustainable Resource Development, Fisheries Management) provided cisco specimens from Cold Lake. Acquisition of much of the northeastern Alberta data presented herein would not have been possible without the field assistance of Stephen Petersen, Matthew Thompson, Guy Hawkings, Nathan Erik, Dominique Simard, Bryan Adcock, and Brian Meagher. A special thank you to Dr. Joseph Nelson (University of Alberta, Department of Biological Sciences) for supervising the initial study of the systematics of shortjaw cisco in Barrow Lake. Funding for that research was provided in part by the Challenge Grants in Biodiversity program, Alberta Conservation Association and by the Northern Scientific Training Program, Canadian Circumpolar Institute. Thanks to Jim Burns (Provincial Museum of Alberta), Joseph Nelson (University of Alberta), Mike Sullivan (Alberta Sustainable Resource Development), James Reist (Fisheries and Oceans Canada), Thomas Todd (Great Lakes Science Center, United States Geological Survey), Robin Gutsell (Alberta Sustainable Resource Development), and Sherry Feser (Alberta Conservation Association) for reviewing this manuscript. Preparation of this report was funded by the Wildlife Management Enhancement Program of the Alberta Conservation Association and the Fish and Wildlife Division of Alberta Sustainable Resource Development. v TABLE OF CONTENTS PREFACE .......................................................................................................................... iii EXECUTIVE SUMMARY ............................................................................................... iv ACKNOWLEDGEMENTS................................................................................................ v INTRODUCTION .............................................................................................................. 1 HABITAT............................................................................................................................ 1 CONSERVATION BIOLOGY............................................................................................ 3 1. Identification .......................................................................................................... 3 2. Reproduction ......................................................................................................... 4 3. Growth ................................................................................................................... 5 DISTRIBUTION................................................................................................................. 7 1. Alberta ................................................................................................................... 7 2. Other Areas ............................................................................................................ 7 POPULATION SIZE AND TRENDS .............................................................................. 11 1. Alberta ................................................................................................................ 11 2. Other Areas .....................................................................................................
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