PHOTO-IDENTIFICATION AND AERIAL SURVEYS OF FLORIDA. MANATEES (Trichechus manatus latirostris) IN MANATEE COUNTY WATERS FINAL REPORT

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1 PHOTO-IDENTIFICATION AND AERIAL SURVEYS OF FLORIDA MANATEES (Trichechus manatus latirostris) IN MANATEE COUNTY WATERS FINAL REPORT Submitted to: William O Shea Planning Department Manatee County Environmental Management Department 1112 Manatee Avenue West Bradenton, FL Submitted by: Mote Marine Laboratory Center for Marine Mammal and Sea Turtle Research 1600 Ken Thompson Parkway Sarasota, FL (941) (941) FAX John E. Reynolds, III, Ph.D., Kerri M. Scolardi, Carolyn Englund, and Ester Quintana-Rizzo Mote Marine Laboratory, 1600 Ken Thompson Pkwy, Sarasota, FL Jul 2006 Mote Marine Laboratory Technical Report Number 1115

2 Introduction: The Florida manatee (Trichechus manatus latirostris) is a herbivorous marine mammal that inhabits the coastal waters of Florida and adjoining states (Reynolds and Odell 1991; Reynolds and Powell 2002). Manatees have inhabited Florida waters since the Pleistocene epoch, nearly 1.5 to 1.1 million years ago (Dawson 1967, Domning 2001). The Florida manatee is a subspecies of the West Indian manatee (Trichechus manatus), one of the four extant species of the order Sirenia. All of the four living species of Sirenia are vulnerable to extinction, mostly due to over-harvesting for food and other products, incidental mortality as a result of human activities, and loss of habitat. Manatees in Florida were hunted for perhaps 10,000 years (Glaser & Reynolds 2003) before a Florida law enacted in 1893 made it illegal to kill or capture a manatee without a permit. The Florida manatee is currently listed as an endangered species by the U.S. government (U.S. Fish and Wildlife Service [USFWS] 2001) and is protected under federal law by the Marine Mammal Protection Act of 1972 and the Endangered Species Act of Manatees are also protected under the Florida Manatee Sanctuary Act of Despite protective legislation, the loss of valuable habitat and increasing mortality from both human-related activities, notably watercraft collisions, and natural causes threaten the recovery of the Florida Manatee (Reynolds 1999, USFWS 2001). Manatees in southwestern Florida are particularly vulnerable, as they are impacted by both natural mortality due to red tides and human activities (e.g., intensive coastal development and boating). The manatee subpopulation in southwestern Florida is the only one, of four, in the state to experience a decline in recent years (Runge et al. 2004).

3 Within Florida, the southwestern region has experienced the fastest growth in human population every decade since 1960 (Smith 2005). Managers are confronted with the difficult problem of accommodating human population growth, while preserving the natural resources that, in part, promote such growth. Conflicts between manatees and human residents of coastal areas of Florida are common because humans enjoy recreational and commercial use of the same habitats that manatees need for feeding, resting, mating and traveling. That such a balance is possible has recently become clear, as the State of Florida found compelling reason to believe that the status of manatees statewide has improved sufficiently to downlist the subspecies from endangered to threatened under state statutes. Resolution of potential conflicts and achieving a balance between human population growth and maintenance of natural resources requires that informed decisions be made. Thus, the collection and rigorous analysis of scientific data can provide information vital to managers and policy makers. To promote informed decision making, Manatee County administrators provided funding to permit the conduct of aerial surveys and photo-identification (photo-id) to establish baselines and to help monitor manatee populations in the county s coastal waters. Aerial surveys provide information on relative abundance and habitat preferences of manatees, whereas photo-identification and subsequent analysis permit assessments of population structure, site fidelity, movement and travel patterns, life history and reproductive traits, and adult survival rates (Ackerman 1995, Beck and Reid 1995, Langtimm et al. 2004, O'Shea & Ackerman 1995).

4 This report provides sighting data from one year of aerial surveys over Manatee County waters and a summary of photo-identification efforts conducted at specific sites during the contract year. Methods: Aerial-Surveys: Mote Marine Laboratory s Manatee Research staff surveyed manatees in the inshore and nearshore waters of Manatee County (Figure 1). A single engine, highwinged Cessna 172 aircraft was flown at an average altitude of 850 ft, and a speed of 90 knots. Flights generally lasted 4-5 hours. Surveys were only flown on days when wind and weather conditions were conducive to effective counting. An experienced primary observer occupied the front, right seat of the aircraft and surveyed with the right window open to reduce glare and increase visibility. Whenever possible, a second observer occupied the right rear seat to help verify counts and scan the water while the primary observer recorded data. All pilots had previous manatee aerial survey experience as well. On a few occasions surveys were flown using a Cessna 182, which had a sealed right window. Therefore, the primary and secondary observers occupied the left side of the aircraft (to survey through the open window) and the pilot operated from the right front seat. The direction of travel was reversed for these flights to accommodate left-side surveying; however the general survey route remained consistent across surveys. The primary observer plotted manatee sightings on photocopied maps of the study area with shoreline, bathymetry and aids to navigation. For each sighting, the observer recorded the number of manatee adults and calves, direction of travel (if any), time, and

5 whenever possible, behavior and habitat. The information recorded on the maps was later transposed into a computerized Geographic Information System (GIS) database using ArcGIS v9.0. Observers also noted weather conditions and visibility. Photo-Identification (Photo-ID): Photo-ID crews conducted surveys from 6-7 meter outboard motorboats, shorelines, bridges, or docks. Vessels were equipped with observation towers, propeller guards and electric trolling motors to minimize disturbance to the manatees. The primary observer operated a Canon EOS 10D or EOS 20D digital camera with 6.3 and 8.20 respective mega pixel resolution and fitted with a mm zoom lens with a polarizing filter. All images were taken in RAW format with embedded jpegs. Occasionally a Canon EOS Elan IIE 35mm SLR camera with 100 ISO Fujichrome slide film was used when necessary. A field day included one or more sites surveyed on a single day. A sighting was defined as all individuals at a geographically distinct location (i.e., canal, bayou, harbor, boat basin) within an approximately km 2 area at the same time. For each sighting, distinctive manatees were photographed to document the position of scars and mutilations on the body. Observers sketched scar patterns and other features on data sheets for each individual and recorded its location, habitat, size class, gender (noted when either the ventrum or a nursing calf was observed) and photographic exposures taken during the sighting. Crews also recorded environmental data, such as weather, water and air temperature, secchi disk reading, salinity, wind direction and speed, and photo conditions.

6 Results: Aerial Surveys: The busy hurricane season of 2005 challenged our survey schedule at the start of the contract period. In early July, two consecutive hurricanes crossed the Gulf of Mexico; as a result only one survey could be conducted that month. Overall, Manatee Research Program staff conducted 23 aerial surveys (roughly 6 each season) between 01 July 2005 and 30 June 2006 (Table 1). Counts of manatees were influenced by the time of year and survey conditions (i.e., cloud cover, sea-state, and visibility) during each flight. Total counts varied considerably among surveys, with the maximum (113 manatees) and minimum (1 manatee) counts occurring just 7 weeks apart on 26 March and 6 February, respectively. Manatee sightings decreased from fall to winter as water temperatures dropped below 18 o C. By mid-march, water temperatures warmed to greater than 21 o C and total manatee counts rapidly increased through the spring. Counts remained high but variable from spring to early summer. Manatee sightings for all months combined showed that virtually all of Manatee County s waterways are inhabited by manatees during some portion of the year (Figure 2). When sightings are broken down by season, however, a shift in distribution is evident. Summer sightings in 2005 (July and August) and 2006 (June) were widely distributed throughout the county, with sightings in Gulf of Mexico, the Manatee and Braden rivers, eastern Tampa Bay, Terra Ceia Bay, Palma Sola Bay, Anna Maria Sound and North Sarasota Bay (Figures 3 and 4). Fall distribution (September, October and November 2005) was also widespread, although sightings within the Manatee River were fewer than in summer months and mostly concentrated in the lower portion of the river

7 (Figure 5). Winter sightings appeared to be more concentrated in the northern regions of the county, particularly throughout eastern Tampa Bay, Terra Ceia Bay and the Manatee and Braden rivers (Figure 6). Distribution was widespread once again during the spring (Figure 7), at which time the easternmost sightings of manatees (in the upper Manatee River) were recorded. Sightings with calves occurred regularly except during winter (Table 1). Inshore protected areas such as Terra Ceia Bay, Palma Sola Bay and the Manatee and Braden rivers appeared provide important for habitat for mother and calf pairs (Figures 8 12). Photo-Identification: Photo-identification (photo-id) studies were initiated during fall 2005 with a few surveys conducted in August and September. Frequency of photo-id surveys increased in the spring, after sufficient aerial survey data were collected to identify locations within the county that had higher probabilities of manatees being present (i.e., to optimize efficiency of photo-id efforts). From 01 July 2005 to 30 June 2006, 74 surveys of 38 sites were completed (Appendix A). Over 1,100 digital and slide images taken during these sightings are currently being sorted and analyzed. Preliminary sorting has shown that cataloged animals from Sarasota Bay, Tampa Bay, and Fort Myers were documented in Manatee County waters this year. There were also a number of unknown but distinctly marked individuals repeatedly sighted in Palma Sola Bay, Terra Ceia Bay, and Anna Maria Sound. Once all of the images have been sorted to determine if they are of known animals catalogued from other locations in previous years, sighting information will be entered into MIPS

8 (Manatee Individual Photo-identification System), a state-wide computerized database for manatee photo-identification data. Distinctive animals that are not identified as being catalogued in previous years will either be catalogued and entered in MIPS, or classified as Distinct Unknown (DU) and given a temporary identification number. The DU animals may then be matched to individual manatees in future field seasons. Discussion: Aerial Surveys: Aerial survey results indicate that manatees use Manatee County waters in relatively high numbers through most of the year. The only time manatees are not widespread and abundant appears to be during the coldest weeks of winter (January and February), when low water temperatures (<20 o C) force manatees to seek warm water refuges outside of the county, such as the Tampa Electric Company power plant located in Apollo Beach. However, the occurrence and concentration of manatee sightings within the northern portions of Manatee County even during winter months indicates that these areas serve as important feeding grounds during warm spells. The peak in total counts during fall and spring is likely due to the migration of animals through the area as they travel between their summer feeding grounds and winter warm-water refuges. During summer months, total counts were moderate to high as manatees dispersed throughout the county to areas that provide forage, access to fresh water, and quiet for calving and resting. However, summer counts in this report comprise surveys from two different years: July and August 2005, and June The average count for summer 2005 (30.3 total manatees) was less than half of the 2006 average (85.5 total manatees).

9 The difference in counts may have been the result of prolonged and re-occurring red tide events that lasted through October Aerial survey studies in Sarasota County also showed relatively low counts of manatees in Sarasota Bay for the summer of 2005 (Mote Marine Laboratory, unpublished). Aerial survey sightings demonstrate that nearly all of Manatee County s waters are utilized by manatees during most or some portion of the year. However, highest concentrations of sightings and/or larger group sizes in areas such as Palma Sola Bay, Terra Ceia Bay, and the Manatee and Braden rivers show a preference by manatees for these locations. Terra Ceia and Palma Sola bays have extensive sea grass beds and deepwater canals and basins that are ideal habitat for feeding and resting. These areas also experience relative low boat traffic, thereby providing quiet areas for mating and calving. Recent analyses of habitat use by manatees in Sarasota Bay demonstrates that groups with calves use habitat differently from groups without calves, with the former demonstrating preference for quirt locations such as protected Pansy Bayou (Gannon et al. in press). Both Terra Ceia Bay and Palma Sola Bay have fresh water input from small streams and, therefore, may also provide access to freshwater to drink. Animals in the Palma Sola Yacht Club boat basin have been observed swimming upstream over the basin dam with their mouths open. Salinities in this basin ranged from 8 to 29 ppt in 2006 surveys. The Manatee and Braden rivers are obviously a significant source of freshwater for manatees; however, these locations provide a limited amount of food and access to quiet (low boat traffic) areas for resting or mating.

10 Environmental conditions such as water clarity, turbidity, surface choppiness and surface glare, all affect the visibility of manatees (Reynolds and Wilcox 1994) and influence both total counts and distribution results. For example, the fact that most of the sightings in the Manatee River during were along the shoreline does not necessarily mean that manatees are not using the deeper portions of the river. Instead, the water clarity is better along the shallow banks, allowing even a bottom resting manatee to be seen from the air. Also, the possible decrease in summer counts due to the presence of red-tide and/or the decrease in water visibility as a result extensive plankton blooms is an example of how total counts and distribution can be affected over specific length of time. Long-term aerial surveys provide the best solution to identifying trends in relative abundance and distribution within a specific region, s well as in providing correlations between environmental conditions and counts. Photo-Identification: Photo-ID surveys of manatees documented distinctly marked manatees, both cataloged and unknown, repeatedly in specific locations throughout the county. Upon completion of slide analyses, data will be used to update, expand, and improve the collaborative statewide scar catalog (MIPS), and establish sighting histories for new, distinctive individuals. The fact that we observed a number of unknown, well marked individuals is interesting, and exciting.

11 Conclusions: The research efforts supported by Manatee County have, in one year, allowed scientists to define high-use areas by manatees within county waters. The surveys have established that manatees are widely dispersed in Manatee County waters, but that certain hot-spots exist. This information is useful to managers who wish to guide development activities in a manner that minimizes impacts to manatees. Supplementing the aerial surveys, photo-id efforts have started to establish a catalog of individuals, including several previously-unknown animals, that occupy Manatee County waters. One year of research on manatees has, thus, provided information that may permit decisions to be made regarding human activities in a manner that also mitigates those activities for manatees. We caution that, given inter-annual variation in weather, environmental conditions, and manatee behavior, additional years of work are needed to establish norms. In that regard, it is encouraging that the surveys will be continued for at least one additional year. We commend Manatee County administrators for initiating research in an effort to provide information that facilitates an effective balance between human population growth and sustainability of manatees in county waters. References: Ackerman, B.B Aerial surveys of manatees: A summary and progress report. Pages in T.J. O Shea, B.B. Ackerman and H.F. Percival, eds. Population biology of the Florida manatee. U.S. Department of the Interior, National Biological Service Information and Technology Report 1.

12 Beck, C.A. and J.P. Reid An automated photo-identification catalog for studies of the life history of the Florida manatee. Pp In T.J. O Shea, B.B. Ackerman, and H.F. Percival (eds.). Population Biology of the Florida Manatee. U.S. Fish and Wildlife Service, National Biological Service, Information and Technology Report pp. Dawson, M.R Fossil history of the families of recent mammals, order Sirenia. Page 45 in S. Anderson and J. K. Jones, Jr. (eds.). Recent Mammals of the World. A Synopsis of Families. Ronald Press Co., New York. 453 pp. Domning, D.P Sirenians, seagrasses and the Cenozoic ecological change in the Caribbean. Palaeogeography, Palaeoclimatology, Palaeoecology 166: Gannon, J.G., K.M. Scolardi, J.E. Reynolds, III, J.K. Koelsch, and T.J. Kessenich. In press. Habitat selection by manatees in Sarasota Bay, Florida. Marine Mammal Science. Glaser, K.S. (photographs) and J.E. Reynolds, III (text) Mysterious Manatees. University Press of Florida, Gainesville. ISBN : 187pp. Langtimm, C.A., C.A. Beck, H.H. Edwards, K.J. Fick, B.B. Ackerman, S.L. Barton, and W.C. Hartley Survival estimates for Florida manatees from the photoidentification of individuals. Marine Mammal Science 20:

13 O'Shea, T. J. and B. B. Ackerman Population biology of the Florida manatee: an overview. Pp In T. J. O'Shea, B. B. Ackerman, and H. F. Percival (eds.). Population Biology of the Florida Manatee. National Biological Service Information and Technology Report pp. Reynolds, J.E. III Efforts to conserve the manatees. Pages in: J.R. Twiss Jr. and R.R. Reeves, eds. Conservation and Management of Marine Mammals. Smithsonian Institute Press, Washington. Reynolds, J.E. III, and D.K. Odell Manatees and Dugongs. Facts on File, New York. Reynolds, J.E., III and J.A. Powell, Jr The manatees--family Trichechidae (Trichechus manatus, T. senegalensis, and T. inunguis). Pp IN: W.F. Perrin, B. Würsig, and H. Thewissen (eds.), Encyclopedia of Marine Mammals, Academic Press, San Diego, CA. Reynolds, J.E. III., and J.R. Wilcox Observations of Florida manatees (Trichechus manatus latirostris) around selected power plants in winter. Marine Mammal Science 10: Runge, M.C., C.A. Langtimm and W.L. Kendall A stage-based model of manatee population dynamics. Marine Mammal Science 20:

14 Smith, S.K Florida Population Growth: Past, Present and Future. Bureau of Economic & Business Research. 02 December 2006: U.S. Fish and Wildlife Service {USFWS} Florida Manatee Recovery Plan, (Trichechus manatus latirostris), Third Revision. U.S. Fish and Wildlife Service. Atlanta, Georgia. 144 pp. + appendices.

15 Table 1: Total counts for each aerial survey conducted from 26 July 2005 through 30 June Weather conditions and water visibility as noted by the primary observer are also shown for each survey date. Bodies of water such as rivers and boat basins typically have poor (<0.5m) visibility; therefore water visibility conditions listed below refer to the enclosed bays and Intracoastal Waterway only. NR: not reported. SURVEY DATE # ADULTS # CALVES # TOTAL WEATHER WATER VISIBILITY (nonriver areas) 7/26/ Good/Fair Good 8/1/ Excellent Good 8/25/ Fair Fair/Poor 9/7/ Good Good 9/28/ Excellent Excellent 10/10/ Fair Good 10/17/ Excellent Excellent 11/3/ Good Good 11/21/ Good Excellent 12/14/ Excellent Excellent 12/22/ Excellent Excellent 1/21/ Good Excellent 1/23/ Good NR 2/6/ Excellent Excellent 2/28/ Excellent Excellent 3/26/ Excellent Excellent 3/30/ Good NR 4/17/ Good Excellent 4/25/ Good Excellent 5/12/ Good NR 5/18/ Fair Good 6/2/ Good Good 6/22/ Excellent Good

16 List of Figures Figure 1. Figure 2. Figure 3. Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure 11. Figure 12. Survey area showing general flight path over Manatee County, FL. Manatee sightings from 24 aerial surveys conducted from 1 July 2005 to 30 June 2006 in Manatee County, FL. Distribution of manatee sightings during summer (July August) 2005 in Manatee County, FL. Distribution of manatee sightings during summer June) 2006 in Manatee County, FL Distribution of manatee sightings during fall (September November) 2005 in Manatee County, FL. Distribution of manatee sightings during winter (December February) in Manatee County, FL. Distribution of manatee sightings during spring (March May) 2006 in Manatee County, FL Distribution of manatee sightings with calves during summer (July August) 2005 in Manatee County, FL. Distribution of manatee sightings with calves during summer (June) 2006 in Manatee County, FL Distribution of manatee sightings with calves during fall (September November) 2005 in Manatee County, FL. Distribution of manatee sightings with calves during winter (December February) in Manatee County, FL. Distribution of manatee sightings with calves during spring (March May) 2006 in Manatee County, FL

17 Figure 1. Survey area showing general flight path over Manatee County, FL.

18 Figure 2. Manatee sightings from 24 aerial surveys conducted from 1 July 2005 to 30 June 2006 in Manatee County, FL.

19 Figure 3. Distribution of manatee sightings during summer (July August) 2005 in Manatee County, FL.

20 Figure 4. Distribution of manatee sightings during summer (June) 2006 in Manatee County, FL.

21 Figure 5. Distribution of manatee sightings during fall (September November) 2005 in Manatee County, FL.

22 Figure 6. Distribution of manatee sightings during winter (December February) in Manatee County, FL.

23 Figure 7. Distribution of manatee sightings during spring (March May) 2006 in Manatee County, FL.

24 Figure 8. Distribution of manatee sightings with calves during summer (July August) 2005 in Manatee County, FL.

25 Figure 9. Distribution of manatee sightings with calves during summer (June) 2006 in Manatee County, FL.

26 Figure 10. Distribution of manatee sightings with calves during fall (September November) 2005 in Manatee County, FL.

27 Figure 11. Distribution of manatee sightings with calves during winter (December February) in Manatee County, FL.

28 Figure 12. Distribution of manatee sightings with calves during spring (March May) 2006 in Manatee County, FL.

29 Appendix A: Photographic identification effort in Manatee County from 1 July 2005 to 30 June On Survey Observation Water Salinity # manatees # Photo'd Date Location Start End Start End Weather Conditions ( C) (ppt) Min Max Min Max 7-Jul-05 LBK, 4500 Gulf of Mexico Dr PC Good Jul-05 LBK, 4500 Gulf of Mexico Dr PC Fair Jul-05 Palma Sola Yacht Basin PC Good Jul-05 Palma Sola, Casco Dorado Apts PC Good Aug-05 Palma Sola Yacht Basin Clear Good Aug-05 Palma Sola, Casco Dorado Apts Clear Good Aug-05 Gulf, NW of Whitney Beach, S of LBP Clear Excellent Sep-05 Palma Sola Bay Clear Excellent Sep-05 Palma Sola Bay Clear Excellent Apr-06 Palma Sola Bay, Mkr C G Apr-06 Palma Sola Bay, NE C G Apr-06 Palma Sola Yacht Basin C G Apr-06 Gulf, South of Longboat Pass C Excellent Apr-06 Palma Sola Yacht Basin C G Apr-06 Palma Sola, Bank of America C G May-06 Terra Ceia Bay, Cut of Mouth C G May-06 Terra Ceia Bay, S C Excellent May-06 Terra Ceia Bay, Tropic Isles C Excellent May-06 Terra Ceia Bay, S C F May-06 Terra Ceia Bay, N C G May-06 Henderson Bay C May-06 Terra Ceia Bay, Colony # C Excellent May-06 Terra Ceia Bay, Colony # May-06 Terra Ceia Bay, W,

30 Appendix A (continued): Photographic identification effort in Manatee County from 1 July 2005 to 30 June On Survey Observation Water Salinity # manatees # Photo'd Date Location Start End Start End Weather Conditions ( C) (ppt) Min Max Min Max 5-May-06 Terra Ceia Bay, Snead Isle Canal # C F May-06 Terra Ceia Bay, Tropic Isles C G May-06 Terra Ceia Bay, W C Excellent May-06 Terra Ceia Bay, Snead Isle Canals C Excellent May-06 Terra Ceia Bay, W C Excellent May-06 Longboat Harbor C F May-06 Palma Sola Yacht Basin PC G May-06 Terra Ceia Bay, Tropic Isles MC G May-06 Bowlees Creek PC G May-06 Palma Sola Bay, W (entrance) PC Excellent May-06 Palma Sola, San Remo PC G May-06 Palma Sola Bay, S PC G May-06 BOA Channel PC F/G May-06 Cortez, SE of Cortez Bridge PC Excellent May-06 Palma Sola Bay, Maker # PC G May-06 Palma Sola, SE PC C May-06 Palma Sola Yacht Basin MC F Jun-06 Palma Sola Bay, W C Excellent Jun-06 Palma Sola Bay, S C Excellent Jun-06 Palma Sola Yacht Basin C Excellent Jun-06 Terra Ceia Bay, S C G Jun-06 Terra Ceia, Tropic Isles Boat Basin C G Jun-06 Terra Ceia Bay, S C G Jun-06 Palma Sola Bay, W C Excellent Jun-06 Palma Sola, E Parrot Cove Canal C G

31 Appendix A (continued): Photographic identification effort in Manatee County from 1 July 2005 to 30 June On Survey Observation Water Salinity # manatees # Photo'd Date Location Start End Start End Weather Conditions ( C) (ppt) Min Max Min Max 8-Jun-06 Cortez, SE Cortez (Cortez Village) C Excellent Jun-06 Cortez Kitchen C G Jun-06 Jewfish Key Grassflats C G Jun-06 Sister Key Flats C G Jun-06 Palma Sola Bay, W C G Jun-06 Palma Sola Bay, SE C G Jun-06 Palma Sola Yacht Basin C G Jun-06 Palma Sola, Bank of America PC G Jun-06 Palma Sola Yacht Basin PC G Jun-06 Terra Ceia, Tropic Isles, PC G Jun-06 Longboat Harbor Yacht Basin PC G Jun-06 Bishop Point to Desoto Point C G Jun-06 Palma Sola Bay, S, outside San Remo PC F Jun-06 Palma Sola Bay, NE PC G Jun-06 Palma Sola Yacht Basin PC G Jun-06 Manatee River, Carlton Arms Basin PC F Jun-06 Manatee River, Werners Bayou PC G Jun-06 Terra Ceia Bay, S PC G Jun-06 Terra Ceia Bay, Tropic Isles PC G Jun-06 Terra Ceia Bay, S C G Jun-06 Terra Ceia Bay, E C G Jun-06 Terra Ceia, Tropic Isles, E Basin C G Jun-06 Terra Ceia Bay, Peterson Bayou PC G Jun-06 Terra Ceia Bay, Champlain Bayou C G Jun-06 Terra Ceia Bay, Snead Isle Canals C F