Feasibility Assessment for the Reintroduction of Fishers in Western Oregon, USA Prepared by Tim L. Hiller March 2015 Feasibility assessment for reintroduction of fishers in western Oregon, USA 2 This report completed in partial fulfillment of U.S. Fish and Wildlife Service Cooperative Agreement Award F14AC00861. Suggested citation: Hiller, T. L. 2015. Feasibility assessment for the reintroduction of fishers in western Oregon, USA. U.S. Fish and Wildlife Service, Portland, Oregon, USA. Cover figure courtesy of Oregon Department of Wildlife (Oregon State Game Commission, Game Division, 1962 annual report). Feasibility assessment for reintroduction of fishers in western Oregon, USA 3 TABLE OF CONTENTS ACKNOWLEDGMENTS .............................................................................................................. 4 OBJECTIVES OF THIS ASSESSMENT ...................................................................................... 6 LIST OF TABLES .......................................................................................................................... 8 LIST OF FIGURES ........................................................................................................................ 9 INTRODUCTION ........................................................................................................................ 11 HABITAT AVAILABILITY........................................................................................................ 12 Coarse-scale Habitat Availability ............................................................................................. 13 Fine-scale Habitat Assessment ................................................................................................. 14 PREY BASE ................................................................................................................................. 16 INTERSPECIFIC EFFECTS ........................................................................................................ 18 Interspecific Killing of Fishers ................................................................................................. 18 Potential Effects on Species of Concern ................................................................................... 21 POTENTIAL SOURCE POPULATIONS ................................................................................... 26 POTENTIAL REINTRODUCTION THREATS ......................................................................... 29 Land Management Decisions .................................................................................................... 29 Climate Change and Wildfires .................................................................................................. 37 Vehicle collisions ...................................................................................................................... 38 Incidental Harvest ..................................................................................................................... 39 Anticoagulant Rodenticides ...................................................................................................... 40 Risks of Small Populations ....................................................................................................... 41 Pathogens and Parasites ............................................................................................................ 42 LEGAL AND REGULATORY REQUIREMENTS .................................................................... 43 State........................................................................................................................................... 43 Federal....................................................................................................................................... 43 NECESSARY ELEMENTS ......................................................................................................... 45 POTENTIAL STAKEHOLDERS AND COOPERATORS ......................................................... 48 CONCLUSIONS AND RECOMMENDATIONS ....................................................................... 48 LITERATURE CITED ................................................................................................................. 51 Feasibility assessment for reintroduction of fishers in western Oregon, USA 4 ACKNOWLEDGMENTS Many individuals from various agencies and organizations provided assistance and expertise to help complete this assessment. Special thanks to Sue Livingston for drafting the Federal Regulations section, reviewing several drafts of the document, and assisting with several other aspects of the assessment; Steve Niemela for drafting the State Regulations section; Craig Thompson for drafting the section on anticoagulant rodenticides; Greta Wengert for drafting the section on interspecific killing of fishers; and Larry Reigel (U.S. Fish and Wildlife Service) for GIS support. Jeff Lewis provided background information, numerous helpful suggestions, and reviewed an initial draft of the assessment. Finally, thanks to all of the reviewers, as their efforts improved the quality and accuracy of this assessment. Inclusion of the names of contributors and reviewers does not necessarily imply endorsement of the contents of this assessment. The U.S. Fish and Wildlife Service provided funding to produce this document. Dr. Tim L. Hiller Forest and Wildlife Research Center Mississippi State University Mississippi State, Mississippi Email: [email protected] List of Contributors Sue Livingston U.S. Department of the Interior Fish and Wildlife Service Oregon Fish and Wildlife Office Portland, Oregon Steve Niemela Rogue Watershed District Oregon Department of Fish and Wildlife Central Point, Oregon Dr. Craig Thompson U.S. Department of Agriculture Forest Service Pacific Southwest Research Station Fresno, California Dr. Greta Wengert Integral Ecology Research Center Blue Lake, California Feasibility assessment for reintroduction of fishers in western Oregon, USA 5 List of Reviewers (accepted invitation to review and returned comments) Dr. Keith Aubry Sue Livingston U.S. Department of Agriculture U.S. Department of the Interior Forest Service Fish and Wildlife Service Pacific Northwest Research Station Oregon Fish and Wildlife Office Olympia, Washington Portland, Oregon Josh Chapman Jamie E. McFadden-Hiller U.S. Department of Agriculture Forest and Wildlife Research Center Forest Service Mississippi State University Pacific Northwest Region Mississippi State, Mississippi Portland, Oregon John Chatel Sean Mohren U.S. Department of Agriculture National Park Service Forest Service Crater Lake National Park Region 6, Threatened and Endangered Crater Lake, Oregon Species Program Portland, Oregon Joe Doerr Steve Niemela U.S. Department of Agriculture Rogue Watershed District Forest Service Oregon Department of Fish and Wildlife Willamette National Forest Central Point, Oregon Springfield, Oregon Dr. Dwayne Etter Michael Rochelle Wildlife Division Weyerhaeuser Company Michigan Department of Natural Resources Lebanon, Oregon East Lansing, Michigan Bruce Hollen Dave Vesely U.S. Department of Interior Oregon Wildlife Institute Bureau of Land Management Corvallis, Oregon Oregon/Washington State Office Portland, Oregon Dr. Jeff Lewis Washington Department of Fish and Wildlife Olympia, Washington Feasibility assessment for reintroduction of fishers in western Oregon, USA 6 OBJECTIVES OF THIS ASSESSMENT The objective of this feasibility assessment is to review and evaluate available information on factors that could affect the success of a fisher reintroduction in western Oregon. The assessment area coincides with the Oregon portion of the proposed West Coast Distinct Population Segment (DPS) delineated by the U.S. Fish and Wildlife Service for the proposed listing of fishers under the federal Endangered Species Act (federal ESA; U.S. Fish and Wildlife Service 2014a,b). It includes all or portions of Benton, Clackamas, Clatsop, Columbia, Coos, Curry, Deschutes, Douglas, Hood River, Jackson, Jefferson, Josephine, Klamath, Lane, Lincoln, Linn, Marion, Multnomah, Polk, Tillamook, Wasco, Washington, and Yamhill counties (Fig. 1). Information about fishers in Oregon was given the highest priority in this assessment, but to fill in various knowledge gaps, it was necessary to also use information from California, Washington, and other areas. A reintroduction (a type of translocation) is, “…an attempt to reestablish a population where one no longer exists within a species’ historical range” (Lewis et al. 2012:2). Consequently, this assessment does not consider the potential consequences of augmenting either of the two extant populations of fishers in southwestern Oregon. A reintroduction of fishers in Oregon would be considered successful in the short term if it resulted in a viable population in the release area(s); it would be successful in the long term if it resulted in population persistence with the opportunity for connectivity with adjacent populations. Beyond assessing whether reintroduction of fishers in western Oregon is feasible, a formal feasibility assessment can have benefits such as increasing public awareness and garnering support of stakeholders, providing the foundation for an implementation plan, and initiating planning efforts for a complex reintroduction project that involves coordination among multiple government agencies and other groups (Berg 1982, Lewis et al. 2012). Although the audience