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• 3 .2 . 2 Nearshore Transect Surveys Y ' Directed research efforts associated with these proposed projects have the potential to answer basic questions about how turtles use nearshore reef habitats . Vessel based transect surveys in the nearshore foraging habitat are proposed to gather data to address two important questions : whether turtles, particularly juvenile green turtles, use nearshore habitats year round; and how the density of turtles varies with distance from shore and at various points along the Indian River County coastline. I Aerial surveys have been used to obtain information on the abundance and distribution of turtles over relatively large areas and are appropriate for documenting seasonal variations in population levels (Henwood and Epperly in Eckert et al. , 1999) (Epperly et al . , 1995) , On the relatively limited geographic scale of Indian River County, it is felt that an analogous vessel based approach is adequate . This monitoring effort will employ observers who will count surfacing turtles from a small boat. A semi -quantitative index, sightings per vesseUkm, will be calculated for each species and compared between seasons and areas. Surveys will be conducted twice a year, generally in the spring and fall, and will include one pre-construction survey. Surveys will be conducted in the year following construction and for two subsequent years, for a total of one pre-construction survey and six post-construction surveys. Surveys will include areas offshore of the Sectors 1 & 2 project area as well as areas offshore of the proposed Sectors 5 and 7 project areas. Surveys outside the Sectors 1 &2 project area will serve as controls for this monitoring plan, and will also serve as baseline data for the other project sectors when and if they are constructed. Three 3 -kilometer long study sites will be established and located in the north, central, and southern areas of the County (Table 2 and Figure 4). Three shore parallel transects will be established in each study site at distances of 300, 600, and 1200 feet offshore. GPS waypoints at the north and south ends of each transect will establish a base course that the helmsman will follow. A constant vessel speed will be maintained for all surveys, verified by GPS track log. The vessel will be equipped with a spotting tower capable of supporting two observers . One observer will look to port and the other to starboard. Observers will record and identify to species any turtle they spot surfacing in each lkm segment of each transect. The resulting mean sightings per vessel km will be statistically compared by ANOVA to determine if there are any significant differences in turtle sighting levels among seasons or among different distances from shore . In the summer of 2001 , this technique was tested in cooperation with FWCC and University of Central Florida researchers, and was found to be practical and capable of collecting useful data. A4