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Temporal tends of persistent organic pollutants in Sarasota Bay common bottlenose dolphins (Tursiops truncatus)



John Kucklick, Ashley Boggs-Russell, Kevin Huncik, Amanda Moors, Elizabeth Davis, Gina Ylitalo, Mary McConnell, Christina Makris, Randall Wells


Legacy persistent organic pollutants (POPs) were measured in blubber samples collected from 196 common bottlenose dolphins (Tursiops truncatus) during 2000 to 2016 in the Sarasota Bay, Florida, ecosystem. Legacy POPs included polychlorinated biphenyl congeners (SPCB), DDT and transformation products (SDDT), chlordanes (Schlor), mirex, polybrominated diphenyl ether congeners (SPBDE), dieldrin and hexachlorobenzene (HCB). Dieldrin was declining most rapidly in male dolphins (-13% per year) while HCB was declining more slowly at 6.3% per year in male dolphins. SPCB, was the POP class present in the highest concentration relative to other POPs and was declining at -8.4%, -7.8%, and -5.6% per year in adult females, adult males and calves, respectively. Relative rates of declines of legacy POPs were generally higher in adult males and lowest in calves. Changes in POP concentration with time based on dolphins captured and released at different time points supports rates calculated in the population cross section. Overall rates of decline in Sarasota Bay bottlenose dolphins were similar to declines seen for Great Lakes fish and about twice the rate of decline observed in arctic data temporal trend data sets. POP trends appear to have leveled off since 2009 in Sarasota Bay dolphins with current concentrations of SPCBs in calves stabilizing at 21 mg/kg lipid. Based on a recent study on killer whales, legacy POPs will continue to suppress dolphin population growth. Results from this study confirm the need for continued monitoring of POPs in the Sarasota Bay bottlenose dolphin population.
Frontiers in Marine Science


Persistent organic pollutant, time trend, Florida, marine mammal


Kucklick, J. , Boggs-Russell, A. , Huncik, K. , Moors, A. , Davis, E. , Ylitalo, G. , McConnell, M. , Makris, C. and Wells, R. (2022), Temporal tends of persistent organic pollutants in Sarasota Bay common bottlenose dolphins (Tursiops truncatus), Frontiers in Marine Science, [online],, (Accessed June 22, 2024)


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Created February 17, 2022, Updated November 29, 2022