Fish spawning aggregations (FSAs) are predictable events where large numbers of conspecifics gather to reproduce, making them vulnerable to overfishing. Permit (Trachinotus falcatus), a highly valued recreational species, form FSAs during the spring full moons in the Florida Keys (USA) that are targeted by anglers. Depredation mortality during catch-and-release angling at these FSAs may undermine the benefits of a harvest prohibition. We therefore conducted fishery-dependent surveys across three primary permit FSAs in the Lower and Middle Keys to assess recreational effort, catch per unit effort (CPUE), and depredation risk. Effort and CPUE peaked during the March-April full moons, coinciding with peak aggregation occurrence. Site-specific differences in recreational effort and CPUE were apparent between the Lower and Middle Keys. At the Middle Keys artificial reefs (Seven Mile Bridge Rubble, Thunderbolt), effort was higher but CPUE was lower, while in the Lower Keys, the natural reef Western Dry Rocks (WDR) exhibited higher CPUE and lower effort, the latter of which decreased after a seasonal fishing closure (SFC) went into effect. Depredation probability was generally low and variable but highest at WDR, increasing since the SFC went into effect, underscoring the risk of depredation during the openly fished March full moon period. Shifts in effort and depredation probability in the Middle Keys are unlikely to be spillover effects related to the WDR SFC but rather due to changes in tourism, angler behavior, and shark occurrence. These results highlight the need for continued monitoring and adaptive management to assess depredation mortality in recreational fisheries and protect vulnerable spawning populations like permit.
