Evaluation of a Spawning Return-Time Mark-Recapture Model for Estimating Lake Sturgeon Population Parameters

Effective management of lake sturgeon (Acipenser fulvescens) is hampered by a lack of basic information (e.g. abundance, mortality rates, etc.) on current populations. Until recently there was no appropriate model to apply to mark-recapture data collected from spawning sturgeon that accounted for the intermittent and highly variable spawning times of males and females. Using an 11 year mark-recapture dataset of spawning lake sturgeon we developed a model that accounts for spawning return-time that can be used to estimate population abundance, annual survival, and other population-level parameters. We will briefly describe the new model and then simulate various sampling scenarios using our long-term dataset to determine model performance under varying levels of annual sampling effort, intermittency, and years of sampling that reflect assessment scenarios managers face. We will then compare simulated sampling scenario results to return-time model output from the full dataset. Based on the result-comparisons between the various simulated sampling scenarios and the full dataset results we will provide advice for managers designing sampling programs for mark-recapture sampling of spawning lake sturgeon and other long-lived iteroparous species.