CItiEt'SW XHPYTD: RSOTLAITYWUAS 4 Monograph of ha, TEMPI, AZ The Native Trouts of the Genus Salmo Of Western North America Robert J. Behnke "9! August 1979 z 141, ' 4,W \ " • ,1■\t 1,es. • . • • This_report was funded by USDA, Forest Service Fish and Wildlife Service , Bureau of Land Management FORE WARD This monograph was prepared by Dr. Robert J. Behnke under contract funded by the U.S. Fish and Wildlife Service, the Bureau of Land Management, and the U.S. Forest Service. Region 2 of the Forest Service was assigned the lead in coordinating this effort for the Forest Service. Each agency assumed the responsibility for reproducing and distributing the monograph according to their needs. Appreciation is extended to the Bureau of Land Management, Denver Service Center, for assistance in publication. Mr. Richard Moore, Region 2, served as Forest Service Coordinator. Inquiries about this publication should be directed to the Regional Forester, 11177 West 8th Avenue, P.O. Box 25127, Lakewood, Colorado 80225. Rocky Mountain Region September, 1980 Inquiries about this publication should be directed to the Regional Forester, 11177 West 8th Avenue, P.O. Box 25127, Lakewood, Colorado 80225. it TABLE OF CONTENTS Page Preface ..................................................................................................................................................................... Introduction ................................................................................................................................................................... 1 Classification: History and Perspective .................................................................................................................. 2 Taxonomic History of Western Trouts ................................................................................................................. 4 Fossils and Ancestors ................................................................................................................................................... 6 Distribution of Parasalmo ........................................................................................................................................... 8 General Life History Notes ....................................................................................................................................... 12 Management and Utilization of Native Trouts .................................................................................................... 13 Habitat Considerations ............................................................................................................................................... 19 Comments on Methods and Principles of Classification .................................................................................... 21 Systematic Accounts of Western Trouts ............................................................................................................... 24 Introduction ............................................................................................................................................................. 24 Causes of Classification Confusion ..................................................................................................................... 24 Cutthroat Trout, Salmo clarki .................................................................................................................................. 27 Introduction ............................................................................................................................................................. 27 Distribution and Taxonomy ................................................................................................................................. 27 Reasons for Decline ................................................................................................................................................ 29 Propagation of Cutthroat Trout ............................................................................................................................ 30 Coastal Cutthroat Trout, Salmo clarki clarki ......................................................................................................... 33 Typical Characters .................................................................................................................................................. 33 Description ............................................................................................................................................................... 33 Distribution ............................................................................................................................................................. 38 Taxonomic Notes .................................................................................................................................................... 38 Life History and Ecology ......................................................................................................................................... 40 Status .......................................................................................................................................................................... 42 The Interior Cutthroat Trout Native to the Columbia and Upper Missouri Basins ..................................... 43 "Westslope" Cutthroat Trout, Salmo clarki lewisi ................................................................................................. 47 Typical Characters .................................................................................................................................................. 47 Description ............................................................................................................................................................... 47 Distribution ............................................................................................................................................................. 48 Taxonomic Notes .................................................................................................................................................... 49 Life History and Ecology ......................................................................................................................................... 50 Status .......................................................................................................................................................................... 51 Yellowstone Cutthroat Trout, Salmo clarki bouvieri ........................................................................................... 53 Typical Characters .................................................................................................................................................. 53 Description ............................................................................................................................................................... 53 Distribuiton .............................................................................................................................................................. 53 Taxonomic Notes .................................................................................................................................................... 54 Life History and Ecology ......................................................................................................................................... 55 Status .......................................................................................................................................................................... 56 Fine-Spotted Snake River Cutthroat Trout, Salmo clarki subsp ......................................................................... 58 Typical Characters .................................................................................................................................................. 58 Description ............................................................................................................................................................... 58 Distribution .............................................................................................................................................................. 58 Taxonomic Notes .................................................................................................................................................... 59 Life History and Ecology ......................................................................................................................................... 61 Status ........................................................................................................................................................................... 62 The Mountain Cutthroat Trout, Salmo clarki alpestris ........................................................................................ 63 Typical Characters ................................................................................................................................................... 63 Description ............................................................................................................................................................... 63 Distribution .............................................................................................................................................................