Genetic and Contaminant Sampling of Bottlenose Dolphins in Charlotte Harbor, Tampa Bay, and Sarasota Bay
By Brian Balmer, Laboratory Research Assistant

Over the past year, biopsy darting efforts have resulted in sampling 48 animals from the Tampa Bay and Charlotte Harbor estuaries. Of the 48 samples collected, all provided a small sample of skin for genetic research and 39 provided blubber for contaminant research. The Tampa Bay field season in August provided 28 samples in 9 field days, from 4 of the 5 Tampa Bay dolphin communities described by Kim Urian. The two Charlotte Harbor field seasons in February and September were successful as well. The February field season concentrated on sampling animals in the Lemon Bay and Gasparilla Sound areas of Charlotte Harbor. In 9 field days, 12 samples were collected, with 7 of the animals sampled having been seen in past survey efforts. The September field season focused on the southern end of Sanibel Island, the waters off St. James City, and Tarpon Bay. Eight samples were collected in 4 field days, with 4 of the sampled animals seen in previous surveys. Genetic samples are being analyzed by Dr. Patty Rosel and Anna Sellas of NOAA Fisheries.

Over the next year, biopsy efforts will be directed towards three areas. The first is sampling animals that are seen in the middle of Sarasota Bay. These animals spend the majority of their time in deep water, making capture, sampling, and release difficult if not impossible. Genetic sampling from this group will provide valuable insight into how these animals fit in the Sarasota dolphin community. The second focus is in Tampa Bay and the collection of additional samples from each of the resident communities there. The final sampling effort will be in northern Charlotte Harbor. This area is the last section of the harbor that has not been sampled. Once samples are collected, a better understanding of Charlotte Harbor bottlenose dolphin community structure will be known.