An individual-based homing model of ontogenetic migration in a coral reef fish using a biased random walk

Migration is an important component of the life history and ecological niche of coral reef fish species.  On the West Coast of Florida, the interaction between ontogenetically migrating reef fish and fishing effort contributes to an important component of fishing mortality.  As a result, a biased random walk model with homing was developed to represent one possible ontogenetic migratory process that reef fish may utilize on the West Florida Shelf.  This model is used to generate and contribute data to a spatially explicit individual-based bioeconomic model which represents the interaction between fisher behavior and fish population dynamics.  Movement from nursery to reef habitat is modeled using a biased random walk while homing behavior is modeled as a function of preferential habitat.  Migration speed is parameterized using conventional tagging data of snapper and grouper in the region.  Results suggest that using a biased random walk with a homing component may be one way to mechanistically understand and model some of the ontogenetic migratory behavior exhibited by reef fish.