Two hatchery-release studies were conducted to evaluate in situ acclimation effects on post-release abundance of juvenile reef fish stocked on small (3 reef units) and large (12 reef units) artificial reefs ∼ 20 km offshore of Sarasota FL. Red snapper Lutjanus campechanus juveniles were hatched and reared at University of Southern Mississippi’s Gulf Coast Research Laboratory in 2001 and 2002, transported to Mote Marine Laboratory in Sarasota Florida and marked with visible implant elastomer and coded wire tags. In spring 2002, 240 red snapper (∼ 9-mos old) were stocked inside and outside of acclimation cages on 3-unit and 12-unit artificial reef complexes. In fall 2002, 1099 red snapper (∼ 4-mos old) were stocked on another set of reef complexes. The stocked snapper were monitored for 13 weeks after spring releases and 5 weeks after fall releases using diver surveys. Rapid depletion of hatchery snapper occurred in both trials within 1 week after release, followed by relatively stable abundance in both trials. In situ acclimation increased short-term abundance by ∼ 3 fold in spring and fall trials, albeit in the spring trial only on the reef complexes with low fish density coupled with large reef size. This study demonstrates stocking red snapper in cages on site for a few days prior to release may increase initial retention of the stocked fish on artificial reefs. Future research to reduce short term post-release mortality of stocked red snapper should consider acclimation in cages prior to release.
Leber et al. (Mon,) studied this question.