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across the reef. The oyster reef is located east of the FDOT ditch discharge point to the Indian River, and therefore, stormwater discharged from the FDOT ditch will flow across the reef. It is expected the oyster population on the reef will remove a significant fraction of the nitrogen load discharged from the FDOT ditch on an annual basis. 4. Oysters were expected to form a dense population on the reef. Oyster spat were expected to colonize and overgrow both living oysters and dead oysters shells, thereby creating a significant mass of dead oyster shells through time. The working hypothesis here was the oyster population will facilitate the removal of phosphorus from the water column flowing across the reef. The accumulation of dead oyster shells will form a long term phosphorus sink within the reef. A detailed survey of the encrusting organisms on the reef was conducted in late December 2013. The results of this survey are summarized below. Estimated Number Species Within Reef Area Anemone 8,500 Barnacles 102,000 Mussels 8,500 Oysters 476,000 Sea Squirts 85,000 Serpulid Worms 4,488,000 A second survey was conducted in July 2014 to estimate the oyster and serpulid worm populations on the reef. The second survey indicated there were 564,000 to 728,000 oysters (95% confidence interval) on the reef structure. The survey also estimated serpulid worm population ranged from 4,969,000 to 5,614,000 individuals (95% confidence interval) on the reef. The oysters generally ranged in size from approximately 1.0 cm to approximately 6.35 cm. The outer surface of the oyster shells were 100 percent covered by other encrusting organisms such as other oysters, serpulid worms, mussels, and periphytic algal species. This data indicates that the colonization rate of encrusting organisms appeared to be moving toward achieving Objective 1. A preliminary survey of the organisms found within the void spaces in the reef also was conducted in late December 2013. One problem noted during this survey was the difficultly in accessing and assessing the species found in these areas. Therefore, the results of this part of the reef assessment definitely under estimated the diversity and density of the species in these areas. The survey did show that stone crabs have colonized the reef, and the estimated population at this time were 728 individuals. Juvenile mangrove snapper also were found within the void spaces, however, it was not Page 2 of 4