Genetic structure of common bottlenose dolphins (Tursiops truncatus) inhabiting adjacent South Florida estuaries – Biscayne Bay and Florida Bay

Coastal common bottlenose dolphins show a variety of migration and residency patterns adding to the difficulty defining stocks for management purposes. Genetic structure plays an important role in identifying population dolphins. This study examines genetic differentiation both between two social groups occurring Biscayne Bay, Florida Bay adjacent group Bay. Skin biopsy samples were sequenced at mitochondrial DNA (mtDNA) control region genotyped microsatellite loci. Significant was found (mtDNA FST = 0.139, p ≤ 0.001; 0.042, 0.001) supporting independent stock status these populations. Within evidence weak but significant using markers (FST 0.0149, 0.009); however, not evident from mtDNA-based estimates φST. The lack mtDNA coupled with field observations indicating overlapping home ranges suggests ongoing, though perhaps low, levels interbreeding. These data are insufficient warrant splitting this time.