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List of Tables 



Table 1. Summary of dolphin abundance estimates from aerial survey data, 

 1975-1994. 



Table 2. Summary of survey effort, 1990-1994. 



Table 3. Annual Charlotte Harbor dolphin population size estimates. 



Table 4. Matrix of number of dolphins identified in one year that were seen in 

 previous or subsequent years, and incidence of transience. See text for 

 explanation of rate derivations. 



Table 5. Young-of-the-year and calf proportions of the mark-proportion annual 

 population estimates. 



Table 6. Summary of known mortalities based on records of stranded dolphins in 

 the counties encompassing the Charlotte Harbor study area. 



Table 7. Proportion of dolphins sighted per kilometer surveyed. 



Table 8. Components of the inter-annual differences in abundance estimates. N] is 

 the Method-3 abundance estimate for Year 1 (Table 3). Mortality is 

 estimated conservatively by the sum of the stranded dolphins reported 

 between surveys (September - August) in S. Sarasota and Charlotte 

 Counties. Reproduction includes two components. The first is the 

 number of YOYs added to the population in Year 2. The second is the 

 number of older calves, which can serve as an index of calf survivorship 

 and /or attractiveness of the area for raising calves. The change in the 

 number of calves is calculated by subtracting the number of calves in Year 

 1 and the number of YOYs in Year 1 (who would be calves in Year 2 if all 

 survived) from the number of calves in Year 2 (Table 5). (This 

 approximation also assumes that the number of calves that become 

 independent of their mothers each year remains constant.) Transients 

 present in Year 1 but not in Year 2 are subtracted; those present in Year 2 

 are added (Table 4). Fluctuations in the number of residents due to 

 movements into or out of the area or due to inability to photograph these 

 dolphins even when present can be estimated by first calculating the 

 difference between Year 1 and Year 2 in the number of marked residents in 

 the catalog (R = M - No. of Transients) and then adding the estimated 

 number of unmarked residents (R * (1 - m/n), Tables 3,4). The Sum of all 

 of these columns can then be compared with N2, the Method-3 abundance 

 estimate calculated for Year 2 (Table 3). The unaccounted-for difference 

 between the Sum and N2 is likely due to imprecision and bias of the 

 abundance estimates or the components listed in the table. 



