Exploring Complexity, Uncertainty, and Risk in Avian Reintroduction Decisions Through Structured Decision Making

Abstract

Avian species reintroductions are a vital tool for mitigating threats and avoiding extinction. However, the decisions required to reintroduce species are overwhelmingly complex. The complexity arises from many interacting factors, including challenges in identifying the specific decision to be made or the alternatives available to the decision maker, limited information about species biology or ecology, unknown effectiveness of management actions, risk of species loss, limited resources, multiple management objectives, multiple distinct management authorities, and lengthy time scales over which actions must be taken. Decision analysis, or structured decision making (SDM), offers a framework for gaining traction on complex decision problems. An SDM process can provide decision makers with a clear view of the decision problem and a clearly defensible justification for the decision. The research I present here explores the use of SDM for informing avian reintroduction decisions through the application of SDM to three case studies: vertebrate (primarily avian) restoration to the island of Guam, management of a reintroduced population of Hihi (Stitchbird; Notiomystis cincta) in New Zealand, and Streaked Horned Lark (SHLA; Eremophila alpestris strigata) reintroductions in Washington State. First, I facilitated a collaborative decision process to determine the problem structure of a complex decision problem regarding vertebrate species restoration in Guam (Chapter 2). Then, using the products of Chapter 2, I developed quantitative models to predict outcomes of alternative restoration strategies for two of Guam’s vertebrate species (Chapter 3). Second, I employed SDM to address the challenge of a struggling reintroduced population of Hihi in New Zealand through the exploration of competing hypotheses about the cause of flat to slightly declining population trends (Chapter 4). Third, I used SDM to develop and evaluate reintroduction strategies for SHLA in Washington State (Chapter 5). Together, these case studies demonstrate how values-based decisions can be made by using all available scientific information to improve the likelihood of successful reintroduction outcomes. Further, my research demonstrates that uncertainty and complexity need not prohibit forward progress toward reaching management objectives.