2018 Dall's Sheep in the White Mountains
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U.S. Fish & Wildlife Service Distribution, movements, and survival of Dall’s Sheep (Ovis dalli dalli) in the White Mountains, Alaska Yukon Flats National Wildlife Mark R. Bertram1, Jim Herriges2, C. Tom Seaton3, Jim Lawler4, Kimberlee Beckmen3 and Sheila Dufford1 Refuge Report 2018-002 October 2018 1 Yukon Flats National Wildlife Refuge 2 Bureau of Land Management th 101 12 Avenue, Room 264 1150 University Avenue Fairbanks, Alaska 99701 Fairbanks, Alaska 99709 3 Alaska Department of Fish and Game 4 National Park Service 1300 College Road 240 West 5th Avenue Fairbanks, Alaska 99701 Anchorage, AK 99501 2 Citation: Bertram, M.R., J. Herriges, C.T. Seaton, J. Lawler, K. Beckmen, and S. Dufford. 2018. Distribution movements, and survival of Dall’s sheep (Ovis dalli dalli) in the White Mountains, Alaska. Refuge report 2018-002. U.S. Fish and Wildlife Service. Fairbanks, Alaska. Keywords: Sheep, Ovis dalli dalli, distribution, movements, survival, White Mountains, Alaska. Disclaimer: The use of trade names of commercial products in this report deos not constitute endorsement or recommendations for use by the federal government. On the cover A family group of Dall’s sheep traverse elevated terrain near Victoria Mountain in the White Mountain. Photgraph courtesy of the U.S. Fish and Wildlife Service. 3 TABLE OF CONTENTS LIST OF FIGURES .................................................................................................................................... 4 LIST OF TABLES ...................................................................................................................................... 4 APPENDIX ................................................................................................................................................. 4 ABSTRACT. ............................................................................................................................................... 6 INTRODUCTION .................................................................................................................................. 7 OBJECTIVES ............................................................................................................................................. 8 STUDY AREA ........................................................................................................................................... 9 METHODS ............................................................................................................................................. 10 Capture and handling ............................................................................................................................ 10 Monitoring of radiocollared sheep ........................................................................................................ 11 Sheep population surveys ..................................................................................................................... 10 Sheep harvest ........................................................................................................................................ 10 Forage quality assessment..................................................................................................................... 10 Parasite, trace element and histopathology assessments....................................................................... 10 Statistical analyses ................................................................................................................................ 10 RESULTS ............................................................................................................................................... 14 Sheep captures .......................................................................................................................................... 10 Home ranges and movements ................................................................................................................... 10 Lambing (May-June) ................................................................................................................................ 10 Mineral licks ............................................................................................................................................. 10 Sheep population surveys ......................................................................................................................... 10 Sheep harvest ............................................................................................................................................ 10 Mortality, Survival rate ............................................................................................................................. 10 Capture myopathy and histopathology ..................................................................................................... 10 Natural mortality ....................................................................................................................................... 10 Survival rate .............................................................................................................................................. 10 Forage quality assessment......................................................................................................................... 10 Parasites .................................................................................................................................................... 10 Trace minerals ........................................................................................................................................... 10 DISCUSSION ........................................................................................................................................ 17 MANAGEMENT RECOMMENDATIONS.................................................................................... 24 ACKNOWLEDGEMENTS................................................................................................................. 24 LITERATURE CITED ........................................................................................................................ 24 4 LIST OF FIGURES Figure 1. Location of Doyon and USFWS exchange lands and access routes, Alaska, USA. ................. 28 Figure 2. Study area, White Mountains sheep, Alaska, USA. .................................................................. 29 Figure 3. Distribution of radiocollared sheep, White Mountains, Alaska, USA, 2004-2008.. ................. 30 Figure 4. Distribution of radiocollared sheep by sex and region, White Mountains, Alaska, 2004-2008.31 Figure 5. Location of sheep lambing areas relative to proposed oil and gas pipeline corridors. .............. 32 LIST OF TABLES Table 1. Historical summary Dall’s sheep surveys, White Mountains, Alaska, USA, 1970 to 2017.. ..... 33 Table 2. Historical summary of Dall’s sheep harvest, White Mountains, Alaska, USA, 1968 To 2017.. 34 Table 3. Dall’s sheep capture statistics, White Mountains, Alaska, USA, 2004-2007. ........................... 36 Table 4. Regional distribution of radiocollared Dall’s sheep by sex and radio collar type, White Mountains, Alaska, USA, 2004-2008. ................................................................................................... 38 Table 5. Corrected estimates of observed Dall’s sheep, White Mountains, Alaska, USA, 2005. ............ 39 Table 6. Summary of capture-related mortalities of Dall's sheep, White Mountains, Alaska, USA, 2004- 2008........................................................................................................................................................ 40 Table 7. Annual survival estimates for Dall's sheep, White Mountains, Alaska, USA, 2004-2009. ........ 41 Table 8. Summary of percent occurrence by forage group in microhistological samples of fecal pellets from Dall’s sheep, by region, month and year, White Mountains, Alaska, USA, 2004-2007. ............. 42 Table 9. Percent nitrogen in fecal pellets for Dall’s sheep by region, month and year, White Mountains, Alaska, USA, 2004-2007. ...................................................................................................................... 42 Table 10. Larvae per gram of lungworm (Protostrongylus stilesi) in captured Dall's sheep by region, sex and age, White Mountains, Alaska, USA, 2004. ................................................................................... 43 Table 11. Larvae per gram of lungworm (Prostrongylus stilesi) in Dall's sheep by region, White Mountains, Alaska, USA, June, 2006. ................................................................................................... 44 Table 12. Range and mean of trace minerals in serum (n = 28) and whole blood (n = 24) samples from Dall's Sheep, White Mountains, Alaska, USA, 2004. ............................................................................ 45 Table 13. Summary of sheep stream crossing by year and age, White Mountains, Alaska, USA, 2004- 2008........................................................................................................................................................ 46 Table 14. Merged minimum convex polygon data for ewe annual movements between 2004 and 2008, White Mountains, Alaska, USA.. ........................................................................................................... 47 LIST OF APPENDICES Appendix A. Radio collar specifications for