IDAHO DEPARTMENT OF FISH AND GAME Steven M. Huffaker, Director Project W-160-R-31 Progress Report HELLS CANYON BIGHORN SHEEP Study I: Hells Canyon Bighorn Sheep Restoration Plan July 1, 2003 to June 30, 2004 By: Francis Cassirer Wildlife Research Biologist September 2004 Boise, Idaho Findings in this report are preliminary in nature and not for publication without permission of the Director of the Idaho Department of Fish and Game. The Idaho Department of Fish and Game adheres to all applicable state and federal laws and regulations related to discrimination on the basis of race, color, national origin, age, gender, or handicap. If you feel you have been discriminated against in any program, activity, or facility of the Idaho Department of Fish and Game, or if you desire further information, please write to: Idaho Department of Fish and Game, PO Box 25, Boise, ID 83707; or the Office of Human Resources, U.S. Fish and Wildlife Service, Department of the Interior, Washington, DC 20240. 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TABLE OF CONTENTS ABSTRACT.....................................................................................................................................1 INTRODUCTION ...........................................................................................................................2 GOAL ........................................................................................................................................2 OBJECTIVES............................................................................................................................2 ACTIONS ..................................................................................................................................3 PROJECT AREA.............................................................................................................................3 POPULATION MONITORING AND MANAGEMENT ..............................................................4 BACKGROUND .......................................................................................................................4 HELLS CANYON INITIATIVE 1997-2003 ............................................................................4 FUTURE DIRECTION .............................................................................................................6 Adult Survival......................................................................................................................6 Lamb Survival......................................................................................................................6 Population Growth...............................................................................................................6 REINTRODUCTIONS AND RELOCATIONS..............................................................................7 BACKGROUND .......................................................................................................................7 HELLS CANYON INITIATIVE 1997-2003 ............................................................................7 FUTURE DIRECTION .............................................................................................................7 Disease Testing ....................................................................................................................8 Release Sites ........................................................................................................................8 Source Populations...............................................................................................................9 HABITAT........................................................................................................................................9 BACKGROUND .......................................................................................................................9 Habitat Availability..............................................................................................................9 Domestic Sheep Grazing Allotments.................................................................................10 HELLS CANYON INITIATIVE 1997-2003 ..........................................................................11 Habitat Acquisitions...........................................................................................................11 Water Developments..........................................................................................................11 Forage Quality ...................................................................................................................11 Weed Control.....................................................................................................................12 Wildfire..............................................................................................................................12 W-160-R-31-xxx Hells Canyon Bighorn Sheep i TABLE OF CONTENTS (Continued) Domestic Sheep Allotments...............................................................................................12 FUTURE DIRECTION ...........................................................................................................12 Habitat Evaluation .............................................................................................................12 Landscape Level ....................................................................................................12 Fine Scale...............................................................................................................13 Public Land Domestic Sheep and Goat Allotments...............................................13 Private Land Domestic Sheep and Goats...............................................................14 Future Habitat Improvements ................................................................................14 RESEARCH...................................................................................................................................15 BACKGROUND .....................................................................................................................15 HELLS CANYON INITIATIVE 1997-2003 ..........................................................................15 FUTURE DIRECTION ...........................................................................................................17 HARVEST .....................................................................................................................................17 INFORMATION AND COMMUNICATION..............................................................................18 ANNUAL REPORT ................................................................................................................18 OTHER COMMUNICATIONS ..............................................................................................19 MEETINGS .............................................................................................................................19 PUBLICATIONS AND REPORTS ........................................................................................19 BUDGET .......................................................................................................................................19 BUDGET VARIANCES .........................................................................................................19 RESTORATION COMMITTEE...................................................................................................20 LITERATURE CITED ..................................................................................................................21 APPENDICES ...............................................................................................................................39 LIST OF TABLES Table 1. Hells Canyon bighorn sheep habitat model. ................................................................31 Table 2. Extent and ownership of potential bighorn sheep habitat in 1997 Hells Canyon habitat analysis area. ....................................................................................................31 Table 3. Hells Canyon Project Area bighorn sheep herd sizes, March 1997 and 2003.............32 Table 4. Comparison of Hells Canyon bighorn sheep herd annual growth rates after initial release and in subsequent years.........................................................................32 Table 5. Hells Canyon bighorn sheep sampling protocol. .........................................................33 W-160-R-31-xxx Hells Canyon Bighorn Sheep ii TABLE OF CONTENTS (Continued) Table 6. Bighorn sheep transplants in Hells Canyon, 1997-2003..............................................33 Table 7. Potential supplemental bighorn release sites, 2004-2007............................................34 Table 8. Wildfires in the Hells Canyon Project Area, 1986-1995. ............................................34 Table 9. Habitat improvements, Hells Canyon Project Area through 2003. .............................35 Table 10. Wildfires in the Hells Canyon Project Area, 1996-2003. ............................................36 Table 11. Permits and harvest of bighorn sheep in Hells Canyon through 2003.........................37 Table 12. Projected annual costs for restoration of bighorn sheep in Hells Canyon, FY 2005 ─ FY 2007. ...................................................................................................38