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NORTHERN SPOTTED OWL (Strix occidentalis caurina)
- Recovery Strategy for the Northern Spotted Owl
- Range Jurisdictions
- Executive Summary
- 1: Background
- 2. Distribution
- 3. Population Abundance
- 4. Biologically Limiting Factors
- 5. Threats to the Species
- 6. Habitat Identification
- 7. Ecological Role
- 8. Importance to People
- 9. Anticipated Conflicts or Challenges
- 10. Knowledge Gaps
- 11. Ecological and Technical Feasibility of Species Recovery
- 12. Recommended Approach / Scale for Recovery
- 13. Socio-economic Considerations
- 14. Recovery Goal
- 15. Recovery Objectives
- 16. Strategies to Meet Recovery Objectives
- 17. Potential Impacts of the Recovery Strategy on Other Species and Ecological Processes
- 18. Actions Already Completed Or Underway
- Literature Cited
- Appendix 1
- Appendix 2
- Appendix 3
- Appendix 4
- Appendix 5
- Appendix 6
- Addendum 1
- Addendum 2
Barrows, C.W. 1981. Roost selection by Spotted Owls: An adaptation to heat stress. Condor 83:302–309.
Barrows, C., and K. Barrows. 1978. Roost characteristics and behavioural thermoregulation in the Spotted Owl. Western Birds 9:1–8.
Bart, J. 1995. Amount of suitable habitat and viability of Northern Spotted Owls. Conservation Biology 9:943–946.
Blackburn, I.R., and S. Godwin. 2003. Status of the Northern Spotted Owl in British Columbia. BC Minist. Water, Land and Air Protection, Surrey, BC.
Blackburn, I.R., and A.S. Harestad. 2002. Supplement to the population assessment of the Northern Spotted Owl in British Columbia 1992–2001. BC Minist. Water, Land and Air Protection, Surrey, BC. 44pp.
Blackburn, I.R., A.S. Harestad, J.N.M. Smith, S. Godwin, R. Hentze, and C.B. Lenihan. 2002. Population assessment of the Northern Spotted Owl in British Columbia 1992–2001. BC Minist. Water, Land and Air Protection, Surrey, BC. 22pp.
Blakesley, J.A., A.B. Franklin, and R.J. Gutiérrez. 1992. Spotted Owl roost and nest site selection in northwestern California. J. Wildlife Management 56:388–392.
Buchanan, J.B., L.L. Irwin, and E.L. McCutchen. 1993. Characteristics of Spotted Owl nest trees in the Wenatchee National Forest. J. Raptor Research 27:1–7.
Buchanan, J.B., L.L. Irwin, and E.L. McCutchen. 1995. Within-stand nest site selection by Spotted Owls in the eastern Washington Cascades. J. Wildlife Management 59:301–310.
Buchanan, J.B., J.C. Lewis, and D.J. Pierce. 1999. Characteristics of young forests used by Spotted Owls on the Western Olympic Peninsula, Washington. Northwest Science 73(4):255–263.
Campbell, E.C., and R.W. Campbell. 1986. Status report on the Spotted Owl, Strix occidentalis, in Canada. COSEWIC, Ottawa, ON.
Campbell, R.W., N.K. Dawe, I. McTaggart-Cowan, J.M. Cooper, G.W. Kaiser, and M.C.E. McNall. 1990. The Birds of British Columbia, Vol. 2, Nonpasserines: Diurnal birds of prey through woodpeckers. Royal British Columbia Museum and Canadian Wildlife Service. Mitchell Press, Vancouver, BC. 636pp.
Canadian Cooperative Wildlife Health Centre. 2003. West Nile virus. Western College of Veterinary Medicine, Saskatoon, SK. Web site: http://wildlife.usask.ca/english/frameWestNile.htm
Carey, A., W. Colgan, III; J.M. Trappe, and R. Molina. 2002. Effects of Forest Management on Truffle Abundance and Squirrel Diets. Northwest Sci. 76:148-157.
Carey, A., S. Horton, and B. Biswell. 1992. Northern Spotted Owls: Influence of prey base and landscape character. Ecological Monographs 62:223–250.
Carey, A., J. Reid, and S. Horton. 1990. Spotted Owl home range and habitat use in southern Oregon coast ranges. J. Wildlife Management 54:11–17.
Caughley, G., and A. Gunn. 1995. Conservation Biology in Theory and Practice. Blackwell Science, Cambridge, MA. 459pp.
Centers for Disease Control and Prevention. 2003. West Nile virus vertebrate ecology. Division of Vector-Borne Infectious Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention (CDC), Atlanta, GA. Web site: http://www.cdc.gov/ncidod/dvbid/westnile/birds&mammals.htm
Dale, V.H., L.A. Joyce, S. McNulty, R.P. Neilson, M.P. Ayres, M.D. Flannigan, P.J. Hanson, L.C. Irland, A.E. Lugo, C.J. Peterson, D. Simberloff, F.J. Swanson, B.J. Stocks, and B.M. Wotton. 2001. Climate change and forest disturbance. BioScience 51:723–734.
Dawson, W., J. Ligon, J. Murphy, J. Myers, D. Simberloff, and J. Verner. 1986. Report of the scientific advisory panel on the Spotted Owl. Condor 89:205–229.
Delaney, D.K., T.G. Grubb, P. Beier, L.L. Pater, and M.H. Reiser. 1999. Effects of helicopter noise on Mexican Spotted Owls. J. Wildlife Management 63:60–76.
Demarchi, D.A. 1998. A spatial simulation model for evaluating the response of rare and endangered species to conservation strategies and forest practices: A case study of the Northern Spotted Owl. M.Sc. thesis, Univ. British Columbia, Vancouver, BC.
Dunbar, D., and I. Blackburn. 1994. Management options for the Northern Spotted Owl in British Columbia. Report of the Canadian Spotted Owl Recovery Team. BC Minist. Environ. Lands and Parks, Surrey, BC. 180pp.
Dunbar, D., Booth, B., Forsman, E., Hetherington, A., and D. Wilson. 1991. Status of the Spotted Owl (Strix occidentalis) and Barred Owl (Strix varia) in southwestern British Columbia. Canadian Field-Naturalist 105:464–468.
Forsman, E.D. 2003. Northern Spotted Owl. Available online at http://biology.usgs.gov/s+t/SNT/noframe/pn172.htm
Forsman, E.D., R.G. Anthony, J.A. Reid, P.J. Loschl, S.G. Sovern, M. Taylor, B.L. Biswell, A. Ellingson, E.C. Meslow, G.S. Miller, K.A. Swindle, J.A. Thrailkill, F.F. Wagner, and D.E. Seaman. 2002a. Natal and breeding dispersal of Northern Spotted Owls. Wildlife Monographs 149:1–35.
Forsman, E.D., and A.R. Giese. 1997. Nests of the Northern Spotted Owl on the Olympic Peninsula, Washington. Wilson Bulletin 109:28–41.
Forsman, E.D., E.C. Meslow, and H.M. Wight. 1984. Distribution and biology of the Spotted Owl in Oregon. Wildlife Monographs 87:1–64.
Forsman, E.D., I.A. Otto, S.G. Govern, M. Taylor, D.W. Hays, H. Allen, S.L. Roberts, and D.E. Seaman. 2001. Spatial and temporal variation in diets of Spotted Owls in Washington. J. Raptor Research 35:141–150.
Forsman, E.D., J.A. Reid, S. Graham, J.S. Mowdy, and A.L. Price. 2002b. Demographic characteristics of Northern Spotted Owls (Strix occidentalis) on the Tyee Study Area, Roseburg, Oregon, 1985–2002. Unpub. report for wildlife habitat relationships in Washington and Oregon, USDA Forest Service.
Forsman, E.D., S. Sovern, and M. Taylor. 2002c. Demography of Spotted owls on the east slope of the Cascade Range, Washington, 1989–2002. Unpub. report for wildlife habitat relationships in Washington and Oregon, USDA Forest Service.
Franklin, A.B., K.P. Burnham, G.C. White, R.G. Anthony, E.D. Forsman, C. Schwarz, J.D. Nichols, and J. Hines. 1999. Range-wide status and trend in Northern Spotted Owl populations. Unpub. report. Colorado State University and Oregon State University, Fort Collins, CO.
Franklin, A.B., R.J. Gutiérrez, P.C. Carlson, D. Pavlacky, J. Rockwiett, W. King, A. Walston, and S. Unger. 2002. Population ecology of the Northern Spotted Owl (Strix occidentalis caurina) in northwestern California: Annual results, 2001. Annual Progress Report for Region 5, USDA Forest Service. 18pp.
Gutiérrez, R.J., A.B. Franklin, and W.S. La Haye. 1995. Spotted Owl (Strix occidentalis). In A. Poole and F. Gill, eds. The Birds of North America No. 179. Acad. Nat. Sci., Philadelphia, PA, and Am. Ornithol. Union, Washington, DC. 28pp.
Hamer, T.E. 1988. Home range size of the Northern Barred Owl and Northern Spotted Owl in western Washington. M.S. thesis, Western Washington University, Bellingham, WA.
Hamer, T.E., E.D. Forsman, D. Fuchs, and M. Walters. 1994. Hybridization between Barred and Spotted Owls. Auk 111:487–492.
Hamer, T.E., D.L. Hays, C.M. Senger, and E.D. Forsman. 2001. Diets of Northern Barred Owls and Northern Spotted Owls in an area of sympatry. J. Raptor Research 35:221–227.
Hamer, T.E., S.G. Seim, and K.R. Dixon. 1989. Northern Spotted Owl and Northern Barred Owl habitat use and home range size in Washington. Preliminary Report, Washington Department of Wildlife. 65pp.
Hanson, E., D. Hays, L. Hicks, L. Young, and J. Buchanan. 1993. Spotted Owl habitat in Washington. Washington Forest Practices Board, Washington. 116pp.
Harper, W.L., and R. Milliken. 1994. Other species associated with late successional forests. Appendix C. in D. Dunbar and I. Blackburn, Management options for the Northern Spotted Owl in British Columbia. Report of the Canadian Spotted Owl Recovery Team. BC Minist. Environ. Lands and Parks, Surrey, BC. 180pp.
Herter, D.R., and L.L. Hicks. 1995. Northern Spotted Owl surveys and demography in the Plum Creek Cascade Habitat Conservation Plan area. Tech. Rep. 1, Plum Creek Timber Company, L.P., Seattle, WA. 79pp.
Hilton, A., and S. Hilton. 2002. Inventory of Northern Spotted Owls: Lillooet Forest District. Unpub. rep. for Minist. Water, Land and Air Protection, Kamloops, BC. 58pp.
Hobbs, J. 2002. Spotted Owl nest searches in the Lillooet Forest District, 2002: Summary of results. Unpub. rep. for Minist. Water, Land and Air Protection, Victoria, BC.
Hodum, P., and S. Harrison. 1997. Ecological assessment of the British Columbia Spotted Owl management plan. Unpub. rep., University of California, Davis, CA.
Horoupian, N., C.B. Lenihan, A.S. Harestad, and I.R. Blackburn. In prep. Diet of Northern Spotted Owls in British Columbia.
Kelly, E.G. 2002. The range expansion of the Northern Barred Owl: An evaluation of the impact on Northern Spotted Owls. M.S. thesis, Oregon State University, Corvallis, OR.
Kelly, E.G., E.D. Forsman, and R.G. Anthony. 2003. Are Barred Owls displacing Spotted Owls? Condor 105:45–53.
Keystone Wildlife Research Ltd. 2003. Spotted Owl data review and management plan for the Fraser TSA. Unpub. draft rep. prepared for Fraser TSA Co-operative Assoc. 53 pp.
Kirk, D.A. 1999. COSEWIC status report on the Northern Spotted Owl, Strix occidentalis caurina. Committee on the Status of Wildlife in Canada. 24pp.
Kurz, W.A., and J.A. Greenough. 1996. Spotted Owl adaptive management program and research needs: Workshop report. Prepared by ESSA Technologies Ltd., Vancouver, BC for the BC Minist. Forests and BC Minist. Environment, Lands and Parks, Victoria, BC. 39pp.
Lamberson, R.H., B.R. Noon, C. Voss, and R. McKelvey. 1994. Reserve design for terrestrial species: The effects of patch size and spacing on the viability of the Northern Spotted Owl. Conservation Biology 8:185–195.
Loye, J.E., and S.P. Carroll. 1998. Ectoparasite behavior and its effects on avian nest site selection. Annals of the Entomological Society of America 91:159–163.
Meidinger, D., and J. Pojar. 1991. Ecosystems of British Columbia. BC Minist. Forests, Victoria, BC. 330pp.
[MELP] B.C. Ministry of Environment, Lands and Parks. 1998. Environmental trends in British Columbia. Minist. Environment, Lands and Parks, Victoria, BC.
Meyer, J.S., L.L. Irwin, and M.S. Boyce. 1998. Influence of habitat abundance and fragmentation on Northern Spotted Owls in western Oregon. Wildlife Monographs 139:1–51.
Miller, A. 2004. Northern Spotted Owl Recovery Strategy for British Columbia, Canada. Unpub. draft rep. 65pp.
Miller, G., S. Small, and E.C. Meslow. 1997. Habitat selection by Spotted Owls during natal dispersal in western Oregon. J. Wildlife Management 61:140–150.
Moller, A.P. 1993. Ectoparasites increase the cost of reproduction in their hosts. J. Animal Ecology 62:309–322.
[MWLAP] B.C. Ministry of Water, Land and Air Protection. 2003. Spotted Owl database. Surrey, BC.
Province of British Columbia. 1995a. Biodiversity guidebook. B.C. Minist. Forests and B.C. Minist. Environment, Lands and Parks, Victoria, BC.
Province of British Columbia. 1995b. Riparian management area guidebook. B.C. Minist. Forests and B.C. Minist. Environment, Lands and Parks, Victoria, BC.
Province of British Columbia. 2003. Identified Wildlife Management Strategy, Vol. 2. B.C. Minist. Forests and B.C. Minist. Environment, Lands and Parks, Victoria, BC.
Ransome, D.B., and T.P. Sullivan. 2003. Population dynamics of Glaucomys sabrinus and Tamiasciurus douglasii in old-growth and second-growth stands of coastal coniferous forest. Canadian J. Forest Research 33:587–596.
[ROMAN] RENEW Operations Manual. 2003. Working draft, 30 January 2003. RENEW Secretariat, Canadian Wildlife Service, Environment Canada, Ottawa.
[SARA] Species at Risk Act. 2003. Chapter 29 of Canada Gazette Part III, Statutes of Canada, 2002. Queens Printer for Canada, Ottawa. 97 pp.
[SOMIT] Spotted Owl Management Inter-Agency Team. 1997a. Spotted Owl management plan: Strategic component. B.C. Minist. Environment, Lands and Parks and B.C. Minist. Forests, Victoria, BC. 81pp.
[SOMIT] Spotted Owl Management Inter-Agency Team . 1997b. Managing Spotted Owl Habitat: Operational Guidelines Component of the Spotted Owl Management Plan. B.C. Minist. Environment, Lands and Parks and B.C. Minist. Forests, Victoria, BC. 39pp.
[SOMIT] Spotted Owl Management Inter-Agency Team. 1999. Spotted Owl Management Plan: Resource Management Plans. B.C. Minist. Environment Lands and Parks and B.C. Minist. Forests, Victoria, BC.
Swarthout, E.C.H., and R.J. Steidl. 2003. Experimental effects of hiking on breeding Mexican Spotted Owls. Conservation Biology 17:307–315.
Thomas, J.W., E.D. Forsman, J.B. Lint, E.C. Meslow, B.R. Noon, and J. Verner. 1990. A Conservation Strategy for the Northern Spotted Owl. Rep. of Interagency Scientific Committee to Address the Conservation of the Northern Spotted Owl (Portland, OR) 427pp + maps.
Thomas, N.J., J. Bunikis, A.G. Barbour, and M.J. Wolcott. 2002. Fatal spirochetosis due to a relapsing fever-like Borrelia sp. in a Northern Spotted Owl. J. Wildlife Diseases 38:187–193.
[USDI] U.S. Department of the Interior. 1992. Recovery plan for the Northern Spotted Owl: Draft. U.S. Fish and Wildlife Service, Washington, DC. 662pp + maps.
[WFPB] Washington Forest Practices Board. 1996. Final environmental impact statement on forest practices rules for Northern Spotted Owl, Marbled Murrelet, Western Gray Squirrel. Washington Forest Practices Board, Olympia, WA.
Wilcove, D. 1987. Public lands management and fate of the Spotted Owl. American Birds 41:361–367.
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