A comparison of population viability measures.

Area of Science:

• Ecology
• Conservation Biology
• Population Dynamics

Background:

• Population viability can be assessed using various metrics like extinction probability or population size.
• Conservation decisions often rely on these viability measures.
• Systematic comparisons of different viability measures and their interconvertibility are lacking.

Purpose of the Study:

• To quantitatively compare eight population viability measures.
• To assess if different measures rank species and scenarios similarly.
• To explore the convertibility of one viability measure into another for comparative studies.

Main Methods:

• Simulated population dynamics for over 4500 virtual species.
• Compared scenario rankings across different viability measures.
• Assessed direct correlations between measures and the influence of model parameters.

Main Results:

• Viability measures showed similar species rankings.
• Direct correlations between measures were often weak and not generalizable.
• Model parameters and data aggregation influence the relationships between measures.

Conclusions:

• While different measures often agree on relative species viability, significant differences can lead to divergent rankings.
• The choice of metric may not alter conservation outcomes in many cases.
• Recommends publishing raw population viability analysis (PVA) data to facilitate meta-analyses and improve risk assessment.