ST. MARYS — An infusion of tagged manatees may help scientists better understand how the gentle giants use coastal Georgia waters, especially near Kings Bay submarine base.
The project, led by Sea to Shore Alliance, the Georgia Department of Natural Resources and Georgia Aquarium, recntly caught eight manatees, fitted with GPS transmitters and returned them to Cumberland Sound. Two of the 13 manatees tracked the past two summers are also still transmitting.
The goal is to map the protected species’ movements near the base, document migratory paths and habitat, and collect data to help assess manatee health.
Although researchers are dealing with expected challenges, such as some manatees quickly shedding the tracking devices that look like miniature buoys, they are also reaping insights into the mammals reclassified from endangered to threatened under the Endangered Species Act last year.
The GPS data have shown that manatees regularly venture into the submarine base, they’re able to find artificial freshwater sources to drink, and a few have traveled into the open Atlantic. Biologists are also confirming things they long suspected but had no way to prove, such as the importance of the Intracoastal Waterway for manatees moving along the coast.
“The Intracoastal Waterway is like a manatee highway,” DNR wildlife biologist Clay George said. “But the ICW is also a primary passageway for boats moving up and down the coast, so this behavior may place manatees at added risk of boat strikes.”
Of the 13 manatees tagged previously, only three have traveled the length of the Georgia coast. “We’re hoping some of the new batch will migrate up the coast toward Savannah, or even South Carolina,” George said. So far, most of the manatees have spent the winter months in Brevard County in east-central Florida, although one migrated more than 500 miles and wintered in Fort Lauderdale.
Understanding habitat use and migration details can benefit manatee conservation efforts, according to Monica Ross of Sea to Shore Alliance.
“We know manatees need warm water to survive,” the research scientist said. “Unfortunately, several manatees are rescued or die from cold stress outside of Florida each year. Through this study, we are gaining a better insight into when manatees make their migration south.”
Manatees migrate from Florida to Georgia in spring, drawn by abundant marsh grass and other aquatic vegetation. They occur in tidal waters throughout coastal Georgia from at least April through October. Yet shorter winters and warming waters have widened that window. Manatees were reported at Kings Bay this February.