Analyzing Long- and Short-Term Population Dynamics to Support Conservation Planning of a Data-Limited Fish, Southern Walleye

Southern walleye (Sander cf. vitreus), a genetically distinct lineage, has declined across its native range in the southeastern United States. Conservation of this data-limited fish requires better understanding of population dynamics, sensitivity to disturbance, and demographic resilience. I developed a deterministic, density-independent, age-structured population projection matrix (PPM) model for females using empirical and theoretical life-history parameters. I evaluated asymptotic and transient dynamics to provide insights for conservation planning. The model projected negative long-term growth (λ₁ = 0.941) but revealed the potential for strong transient effects, especially following strong recruitment events. Early life-stage survival had the greatest influence on growth and persistence. Scenario analyses suggested that favorable spawning conditions, conservation stocking, and targeted translocation could produce short-term gains under the assumed model structure, whereas even moderate harvest reduced population growth. Interacting effects, density-dependent processes, and spatial structure were not considered and could yield more nuanced outcomes, but these results help clarify demographic sensitivities, potential management leverage points, and priorities for future investigation. Additionally, the approach taken demonstrates how alternative conservation actions can be compared for their ability to meet management objectives and navigate tradeoffs. These results highlight the need to consider both short- and long-term dynamics when evaluating management actions and engaging in planning activities for at-risk species.