Fine-scale movement of northern Gulf of Mexico red snapper and gray triggerfish estimated with three-dimensional acoustic telemetry

Abstract

Red snapper and gray triggerfish are ecologically, economically, and culturally important reef fishes in the northern Gulf of Mexico (nGOM). Scientists and managers have sought to understand the effects of artificial reefs on reef fish ecology by focusing on fish residency and movement at artificial reefs with less attention paid to broader spatial and temporal patterns in reef fish movements among a seascape of artificial reefs and other natural habitats. We used novel large-scale (> 15 km2) geopositioning acoustic telemetry arrays to track the 3-dimensional movements of tagged red snapper (n = 59) and gray triggerfish (n = 15) among multiple nGOM artificial reefs up to 333 days. Tagged fish moved frequently among artificial reefs and had shorter residence times at the release reef (43 days for red snapper and 3 days for gray triggerfish) than reported in previous studies. Both species displayed high individual variability in movement dynamics, as well as seasonally variable diel patterns of habitat use, height above bottom, and distance to reefs, which may have been driven by dynamic influences of predation risk, physiological constraints, or foraging over time and space. The wider seascape view revealed in this study demonstrates the importance of including multiple artificial reefs over long timescales to capture individual, spatial, and temporal variability in reef fish movement.