Habitat preferences and site fidelity of juvenile red snapper (Lutjanus campechanus)

Abstract

Ten small reefs constructed of either oyster shell or polyethylene webbing and ten randomly selected open-bottom sites within a distance of 3.7 km of the reefs were used to determine juvenile red snapper [Lutjanus campechanus (Poey, 1860)] habitat preferences. The reefs were deployed at 40, 50, 70, and 90 m from a flare stack located in a gas field off the coast of Mississippi. Juvenile red snapper were observed at one of the open-bottom sites when it was first surveyed, but none during a second survey conducted 45 days later. Age-0 and age-1 fish showed a preference for the more complex study reefs, but presence of age-1 appeared to limit recruitment of age-0 to a reef. As age-1 fish started to leave the reefs, increased numbers of age-0 were observed moving onto them. However, age-0 were never observed at the 40-m reef occupied by older fish throughout the study. Distance from the flare stack also appeared to have an effect on recruitment to the reefs. Age-0 were first observed at the 50-m reefs. They appeared at the 70-m reefs a week later and at the 90-m reefs almost a month later. Age-1 fish showed a preference for the reefs located closest to the flare stack. Juvenile red snapper site fidelity was determined using fish that either were tagged and released on site or were removed from the capture site before release. Fish from the on-site release were repeatedly sighted at the capture reef over about a 2-month period. Displaced fish, as determined with tracking equipment, were able to find their way back to the capture reef from as far away as 0.43 km in about 25 min. We conclude that juvenile red snapper are not only faithful to structures, but also have homing capabilities.