WALL, L.M.*; WALTERS, L.J.; SACKS, P.; HOFFMAN, L.; University of Central Florida, Orlando, Florida 32816; University of Central Florida, Orlando, Florida 32916; Deltona High School, Science Department, Deltona, Florida 32725; University of Central Florida, Orlando, Florida 32916: Recruitment and restoration protocol for the oyster Crassostrea virginica on intertidal reefs in areas with intense boating activity

Productivity, diversity and survival of estuaries are threatened by explosive coastal population growth and associated recreational activities. One major area of recreational growth has been the number of small pleasure craft motoring in shallow waters at high speeds. On the east coast of Central Florida in the Indian River Lagoon system, intense boating activity occurs year-round and intertidal reefs of the eastern oyster Crassostrea virginica with dead margins (piles of disarticulated shells) on their seaward edges are commonly found. The cause(s) of the dead margins is unclear. However, the disarticulated shells may be reducing reef sustainability if these surfaces are unavailable for larvae. Recruitment trials were run on eight reefs (4 with dead margins, 4 without) in three 8-week trials in 2001/2002. Significant seasonal differences were identified for recruitment and survival. Based on these results, experimental restoration began May 2003 to develop an ecologically and economically feasible restoration protocol for this intertidal region. Four different densities of shells (0, 16, 25, 36) were attached to vexar mesh mats (45 X 45 cm) displaying shells perpendicular to the substrate. 360 mats were randomly deployed at one of six identified optimum recruitment locations. Recruitment increased through June and was significantly higher on mats with 36 shells. This was followed by a large, expected decline in recruitment and survival in July/August, due to competition, predation and/or extreme high temperatures. These newly-created oyster reefs are moveable and provide optimal substrate and larval set to be transported post-recruitment to areas resource managers have slated for restoration to aid in reef sustainability.