68: Heterogenous Velocity Models Help Identify Differences in the Movement of Invasive Species

Music City Center 

Brown treesnakes are an invasive species in Guam, threatening the island's biodiversity and posing costly implications for the local economy. They also present a threat to neighboring islands through shipping channels. Rapid response efforts are organized to capture individuals and prevent the emergence of incipient populations once individuals are detected. Previous methods have highlighted the importance of individual-level heterogeneity in movement parameters. However, it has remained difficult to detect differences among the experimental treatment groups that incorporate information on the snake's habitat of origin. We propose a Bayesian hierarchical model that enables inference on treatment-level dynamics by applying shrinkage to individual-level movement rate parameters. This multilevel model allows for heterogeneity in velocity to estimate movement rates at the treatment-level while still allowing for variation among individuals. We demonstrate our approach using data collected from a telemetry-based study and environmental covariates to learn the treatment-level effects. This framework can also be used to predict brown treesnake movement in Guam.