NEWS RELEASE

Scientists at FAU’s Harbor Branch Oceanographic Institute believe genetic testing may be the key to solving many mysteries surrounding dolphins in the Indian River Lagoon (IRL) and beyond. Their research, involving the genetic testing of over 600 dolphins sampled both within the lagoon and along the adjacent Atlantic coastline, sheds new light on the population structure and dispersal patterns of the dolphins that inhabit the Indian River Lagoon.

The study, conducted by FAU Harbor Branch research biologist Sarah Rodgers under the guidance of principal investigator Gregory O’Corry-Crowe, Ph.D., examined two different types of genetic markers, or parts of the genome, in dolphins – one from the mother and the other from both parents. Scientists found distinct genetic differences between dolphins in the Lagoon and those in the Atlantic Ocean.

Researchers also uncovered discrepancies in the theory that the Lagoon dolphin population is a “closed population,” meaning all IRL dolphins stay in the lagoon and do not interact with Atlantic dolphins. Several of the dolphins sampled in the Lagoon had full Atlantic genetic profiles, despite, in some cases, being sighted and tracked within the lagoon for over a decade and sampled during lagoon health assessments. Further, scientists discovered several dolphins with a genetic background likely indicating one Lagoon parent and one Atlantic parent. The DNA also revealed dramatic differences between dolphins in Mosquito Lagoon and the Lagoon proper. Moreover, it appears that movements of dolphins between Mosquito and the Atlantic Ocean may be highly dynamic verses that of movement between the Lagoon proper, suggesting the Mosquito Lagoon estuary functions differently than the rest of the Lagoon.

The findings from this study, coupled with other genetic and genomic dolphin research being conducted by O’Corry-Crowe’s group, could help to provide new answers for health and management issues surrounding the recent mass die-off of dolphins spanning the entire Atlantic eastern seaboard. Rodger’s current genetic research is focused on investigating the Mosquito Lagoon phenomenon.