17 



period, as discussed under "Methods". All available data indicate that permanent 

 immigration and emigration were rare occurrences. None of the more than 900 

 dolphins identified from Sarasota Bay (1975-1994) and Tampa Bay (1975-1993), the 

 adjacent waters to the north, nor the 272 dolphins in photographs provided by 

 Shane from her Pine Island Sound study area immediately to the south, were 

 identified as immigrants to the Charlotte Harbor area during our study. Conversely, 

 none of the 411 dolphins identified from Charlotte Harbor waters during 1990-1994 

 were observed to take up residence in Sarasota Bay or Tampa Bay. 



Residency to portions of the Charlotte Harbor study area was suggested by 

 repeated sightings of some individuals in the same waters over multiple years. 

 Sixteen of the 411 dolphins in the catalog (3.8%) were also seen in the area prior to 

 the initiation of the surveys in 1990. Twelve of these were first identified during 

 1982 - 1984. Twenty-seven dolphins (6.6%) were identified from the Charlotte 

 Harbor studv area during all five of the survey years; 97 (23.6%) were seen during at 

 least four of the five survey years. 



We did not find animals with regular movements through the entire study 

 area when we examined those seen in multiple years, and those with the requisite 

 15 or more sightings needed for description of a home range (Wells 1978). Instead, 

 we found clusters of sightings within localized areas, as has been described 

 elsewhere along the central west coast of Florida (Wells 1986; Wells et al. 1995). For 

 example, "CURL" was seen frequently in Lemon Bay during 1990 - 1994 (Figure 10 a). 

 Sightings of dolphins such as "THUV" (1982 - 1991, Figure 10 b), "HISC" (1990 - 1994, 

 Figure 10 c), and "TSMD" (1990 - 1994, Figure 10 d) were concentrated in Gasparilla 

 Sound. Long-term sightings of dolphin "RPPR" (1982 - 1994, Figure 10 e) were 

 spread through both Lemon Bay and Gasparilla Sound. Sightings of dolphin 

 "LGSL" (1982 - 1994, Figure 10 f) were concentrated in and near the deep waters of 

 Boca Grande Pass. "TFLN" (1982 - 1993, Figure 10 g) was seen repeatedly in the 

 shallows in northern Pine Island Sound. Dolphins "CLTO" (1982 - 1992, Figure 10 h) 

 and "ZIGY" (1990 - 1994, Figure 10 i) were seen primarily in the open, deeper waters 

 of southern and western Charlotte Harbor proper. Dolphin "POTP" (1990 - 1994, 

 Figure 10 j) was seen primarily in the shallow waters of eastern Charlotte Harbor. 

 Little can be said about the year-round residency of these animals, except that all of 

 the catalog members identified prior to the surveys were seen in months other than 

 August. While these examples provide documentation of the tentative existence of 

 long-term home ranges in the Charlotte Harbor area, they should not be interpreted 

 as indicating that all of the dolphins in the area fall into these patterns. Additional 

 sightings during different seasons would be required to accurately assign home 

 ranges or other movement patterns to the dolphins in Charlotte Harbor. 



Movements back and forth between Charlotte Harbor and waters to the north 

 were recorded for ten (2.4%) dolphins of the 411 in the Charlotte Harbor catalog. A 

 few individuals, such as "DIPT" (Figures 10 k,l) appear to spend equivalent amounts 

 of time in southern Sarasota, Lemon Bay, and Gasparilla Sound, suggesting the 

 existence of a home range connecting these two regions. Others, such as"RY34" 



