Great Big Fish Tales: Long-Term Monitoring of Goliath Grouper After Catch and Release

Goliath grouper (Epinephelus itajara) have been protected from harvest within US waters for over two decades. Despite the moratorium, the species continues to be targeted for catch and release and is also caught inadvertently as bycatch. Mortality due to directed or incidental fishing pressure is unclear. This study was established to identify survival of goliath grouper after a catch and release event, and to quantify long term residence and behavioral patterns. Goliath grouper were caught on hook and line, fitted with acoustic tags and monitored via an array of acoustic receivers within the Gulf of Mexico (13 artificial reefs were monitored within a 2,000 km² area; depth ranged 10 – 40 m). Pressure sensors indicated fish location within the water column, providing confirmation of movement and survival. Between April 2011 – January 2012, 32 individuals (105 – 205 cm TL) were monitored for periods up to 258 days (14 – 258 d; mean = 108 d). In August, coincident with the suspected spawning season, 30% of tagged fish disappeared from their “resident” sites. By October, almost all had returned. Preliminary results indicate high site fidelity and suggest relative resilience to catch and release fishing, at least over periods of weeks – months.