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Climate-Change Vulnerability Assessment for Priority Wildlife Species

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Climate-Change Vulnerability Assessment for Priority Wildlife Species Climate-Change Vulnerability Assessment for Priority Wildlife Species Prepared for: The Navajo Nation Department of Fish and Wildlife In Partnership With: The H. John Heinz III Center for Science, Economics and the Environment 2 Report Submitted: October 30, 2013 The H. John Heinz III Center for Science, Economics and the Environment Jonathan Mawdsley, Ph.D., Program Director Rachel Lamb, Project Assistant With assistance from: Matthew Grason, Sandra Grund, Schneka Hines, Dennis Murphy, Martha Surridge, Caroline Sweedo, Stacia VanDyne Thank you to all Navajo Nation members and NNDFW staff who contributed their time to this effort. We especially thank Gloria Tom for her leadership and Jeff Cole and Leanna Begay for their gracious assistance with this project. 3 Table of Contents 1. Executive Summary .....................................................................................................................5 2. Introduction ...................................................................................................................................6 2.1 Purpose of this Document ..................................................................................................... 6 2.2 Overview of the Navajo Nation and its Lands......................................................................... 6 2.3 Overview of Navajo Nation Department of Fish and Wildlife (NNDFW) .................................. 6 2.4 Scope of the Document ......................................................................................................... 7 3. Methodology for Climate Vulnerability Assessment ..........................................................9 3.1 Key Components of Vulnerability .......................................................................................... 9 3.2 Metrics for Assessment ....................................................................................................... 10 3.3 Steps for Addressing Vulnerability and Increasing Resilience ............................................... 11 4. Climate Change in the Southwestern United States ........................................................ 13 4.1 Projected Climate Changes in Region ................................................................................. 13 4.2 Climate Change Related Stressors ...................................................................................... 13 4.2.1 Increased Drought Severity ................................................................................. 13 4.2.2 Wildfires ............................................................................................................. 14 4.3.3 Flooding .............................................................................................................. 14 4.4.4 Shifts in Species Distribution and Range .............................................................. 15 4.4.5 Changes in Water Availability .............................................................................. 15 5. Plant Species .............................................................................................................................. 17 5.1 Process for Species Selection ............................................................................................. 17 5.2 Pinyon Pine ....................................................................................................................... 17 5.3 Yucca ................................................................................................................................. 18 5.4 Mesa Verde Cactus ............................................................................................................ 18 5.5 Navajo Sage ....................................................................................................................... 19 5.6 Salt Cedar (Tamarisk spp.) ................................................................................................. 20 6. Wildlife Species ........................................................................................................................ 22 6.1 Process for Species Selection ............................................................................................. 22 6.2 Methods for Climate-Change Vulnerability Assessment........................................................ 22 6.3 Golden Eagle (Aquila chrysaetos) ....................................................................................... 23 6.4 Mule Deer ......................................................................................................................... 25 6.5 Desert Bighorn Sheep ........................................................................................................ 28 6.6 Mountain Lion ................................................................................................................... 30 6.7 American Black Bear........................................................................................................... 32 6.8 Vulnerability and Resilience Rankings Across all Species ..................................................... 35 7. Development of Climate Adaptation Strategies ............................................................... 36 7.1 General Climate-Change Adaptation Recommendations .................................................... 36 7.2 Adaptive Management as a Tool for Climate-Change Adaptation ...................................... 37 4 7.3 Guides for Adaptive Management: Modeling and Monitoring ........................................... 38 7.4 Specific Climate Adaptation Strategies for NNDFW................................................................ 39 7.4.1. Connectivity Analysis and Corridor Conservation.................................................. 39 7.4.2 “Climate Smart” Species Translocation................................................................... 40 7.4.3 Renewable Energy and Golden Eagles.................................................................... 40 7.4.4 Reducing Human Conflict with Black Bears............................................................ 40 7.4 Connectivity Analysis Leads to Management Prescriptions ................................................. 41 8. References ................................................................................................................................... 43 9. Appendix – Useful Figures for Understanding Climate Change .................................... 47 5 1. Executive Summary The Navajo Nation Department of Fish and Wildlife and the H. John Heinz III Center for Science, Economics and the Environment jointly developed a climate-change vulnerability assessment for priority wildlife and plant species and habitats on the Navajo landscape. The priority species and habitats included in this analysis were identified by the entire staff of NNDFW through a structured planning process. This report provides a summary of projected climate-change impacts for the southwestern United States and Navajo lands as well as an assessment of attributes promoting climate vulnerability and resilience for priority wildlife and plant species. Animal species discussed in this report are the Golden Eagle, Mule Deer, Desert Bighorn Sheep, Mountain Lion, and American Black Bear. Plant species discussed in this report include Pinyon Pine, Yucca spp., Mesa Verde Cactus, Navajo Sage, and Salt Cedar (Tamarisk). This vulnerability assessment provides a conceptual framework for further climate adaptation planning on the Navajo landscape within an adaptive management context. Specific climate adaptation actions that are proposed in this report include: conservation of wildlife movement corridors; “climate smart” reintroductions of Desert Bighorn Sheep; consideration of Golden Eagles in the planning and siting of renewable energy developments; and actions to reduce human conflicts with Black Bears. An example is provided to show how landscape connectivity analyses can be used to identify areas where “on-the-ground” conservation actions can be implemented. 6 2. Introduction 2.1 Purpose and Scope of this Document This document summarizes the results of a collaborative project between the Navajo Nation Department of Fish and Wildlife (NNDFW) and the H. John Heinz III Center for Science, Economics and the Environment (the Heinz Center), to identify management actions that NNDFW could take to reduce or ameliorate the effects of climate change on key wildlife species and their habitats. The current Strategic Plan for the Navajo Nation Department of Fish and Wildlife (NNDFW) recognizes the importance of incorporating information about climate change into the Department’s existing plant, habitat and wildlife management activities. Through the strategic planning process, the entire staff of NNDFW worked together to identify a set of high-priority plant and animal species and wildlife habitats for management focus and attention. With follow-on funding from the Bureau of Indian Affairs, NNDFW and the Heinz Center compiled information about potential and observed climate-change impacts on these species. This information was discussed at two meetings of the entire NNDFW staff in 2012 and 2013, and a set of provisional climate adaptation strategies was developed. In one case, these strategies led to the identification of specific, “on the ground” conservation actions that could help maintain landscape connectivity for large mammal species in the face of climate change. The report is intended to serve
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