Using Decision Science for Monitoring Threatened Western Snowy Plovers to Inform Recovery

Area of Science:

• Wildlife conservation
• Population monitoring
• Endangered species management

Background:

• Western Snowy Plovers (Charadrius nivosus nivosus) are federally listed as Threatened along the US Pacific coast.
• Threats include habitat loss, predation, and human disturbance, necessitating long-term population monitoring.
• Recovery actions since 1993 have led to population growth, creating challenges for optimal monitoring strategies.

Purpose of the Study:

• To evaluate nine alternative monitoring strategies for Western Snowy Plovers using structured decision analysis.
• To identify the most effective and cost-efficient monitoring approaches aligned with recovery goals.
• To provide a framework for consistent monitoring methods across the species' range.

Main Methods:

• Structured decision analysis incorporating multi-attribute utility theory.
• Involvement of plover biologists to score monitoring strategies based on performance measures.
• Evaluation of four scenarios considering objective weighting and risk attitude.

Main Results:

• Six Pareto optimal monitoring strategies were identified as best meeting recovery needs and cost-efficiency.
• The analysis revealed trade-offs between different monitoring objectives and the impact of risk attitude.
• Results were presented to the US Fish and Wildlife Service for implementation and consistency.

Conclusions:

• Structured decision-making provides an optimal framework for selecting monitoring strategies for recovering species.
• This approach ensures effective and cost-efficient management of Western Snowy Plovers.
• The methodology is transferable to other imperiled species undergoing recovery.