Direct Estimates of Hook Selectivity for Gulf of Mexico Reef Fishes

Project Leader: Dr. William F. Patterson

Project Details

Fishing gear selectivity is an important parameter in stock assessment models, but it is also critically important for estimating population trends within fishery-independent monitoring programs. Typically, the functional form (e.g., dome- or logistic-shaped) of selectivity is imposed in assessment models, and selectivity in recreational fisheries most often is assumed to have a logistic shape (i.e., fish remain fully-selected by the gear after they reach the size at full selectivity). Along with collaborators at the National Marine Fisheries Service and a group of charterboat captains, we developed a method that employs a micro remotely operated
vehicle equipped with a laser scaler to estimate hook selectivity directly. Early results indicate dome-shaped selectivity functions exist for a range of circle hook sizes, as well as significant differences in catch rate, hooking location (e.g., jaw, gills, esophagus, or foul hooked), and size at full selectivity for similar sized circle versus J hooks. Funding source: National Marine Fisheries Service’s Cooperative Research Program.