More Manatees Tracked to Map Movements in Georgia, Assess Health

St. Marys, GA
Monday, May 23, 2016 - 10:30

 

 

Another five manatees fitted with GPS transmitters are being tracked in Georgia, the second year of a project providing valuable insight into how these big and rare mammals use estuarine waters near Kings Bay submarine base and along the rest of Georgia’s coast. The health of the manatees is also being documented.

Wildlife agencies and organizations from Georgia and Florida teamed up May 2-3 to net the manatees, collect samples, fit the animals with satellite devices and return them unharmed to Cumberland Sound.

The five are the second group tagged in a multi-year effort to map the endangered species’ movements near Naval Submarine Base Kings Bay, document migratory paths and habitat use in the Southeast, and collect baseline data to help assess manatee health. Partners include the Georgia Department of Natural Resources, Georgia Aquarium and Sea to Shore Alliance, along with other agencies that helped capture, assess and release the animals.

The manatees tracked since last summer have produced surprises, such as frequently traveling in small creeks in addition to the Intracoastal Waterway, DNR wildlife biologist Clay George said. Understanding that use and the timing of manatee migration can help improve conservation of the protected animals.

The key is fine-scale GPS data, a first for manatees followed in Georgia. “We’re getting literally breadcrumbs of their movements,” said George, who leads marine mammal research for DNR’s Nongame Conservation Section.

Manatees migrate each spring from Florida to Georgia, attracted by abundant marsh grass and other aquatic vegetation. They occur in tidal waters throughout coastal Georgia from April through October.

The large, slow-moving animals swim just below the surface, often putting them in harm’s way of oncoming boats. Watercraft collisions caused 28 percent of the manatee mortalities documented in the state since 2000. The statistic highlights the need to better understand manatee movements in Georgia.

Earlier this month, the team used a DNR helicopter to spot manatees. Clearwater Marine Aquarium’s capture boat deployed a net to encircle the half-ton animals. Biologists and Georgia Aquarium and SeaWorld Orlando veterinary staff examined those caught – all adult males – took samples, fitted each animal with transmitters and released them. The transmitter, tethered to a belt wrapped around the tail, floats at the surface behind the manatee.

The captures were done a month earlier than last year in hopes of gaining more data while the manatees are in Georgia. All of the 2015 group – only one of which is still transmitting – returned to Florida within two months, said research scientist Monica Ross of Sea to Shore Alliance, one of the project’s leaders.

Ross monitors the manatees daily online, and with George will regularly check them on the water.

“At least every two weeks, we’ll get eyes on each animal, to see what they are doing, check the equipment and take the opportunity to photo ID other animals they might be with,” Ross said. “If at any point the tag activity is abnormal, we will get eyes on the animals immediately.”

The tracking device does not impede the manatee’s movement or pose a risk of entanglement. The belt, the tether linked to the transmitter and the tag itself are each designed to part easily.

Georgia Aquarium is directing the health assessment studies, which are patterned after the Aquarium’s long-standing bottlenose dolphin Health and Environmental Risk Assessment research in Florida’s Indian River Lagoon, said Dr. Gregory Bossart, Georgia Aquarium senior vice president and chief veterinary officer.

Aquarium staff from animal health and research and conservation departments, including Georgia Aquarium’s Conservation Field Station in Florida, took part. “We are starting to generate important first-time health data from manatees in Georgia,” Bossart said. “This information tells us not only about manatee health but also provides important new clues about the health of the environment and potentially human health.”

Project funding has been provided by Commander, Navy Region Southeast; the U.S. Fish and Wildlife Service; Georgia Aquarium; Georgia Nongame Wildlife Conservation Fund; The Environmental Resources Network, or TERN (friends group of DNR’s Nongame Conservation Section); and, Sea to Shore Alliance.

Staff from the National Park Service, Clearwater Marine Aquarium, U.S. Geological Survey, U.S. Coast Guard, National Marine Mammal Foundation, Science Applications International Corp., U.S. Navy, Fish and Wildlife Service and Florida Fish and Wildlife Conservation Commission also helped in capturing the manatees.

As of late May, the newly tagged manatees were on the move, with two venturing north near Brunswick, two hanging out in Camden County waters and one turning south into Florida.

Project images are posted at www.flickr.com/photos/wildliferesourcesdivision (in the “Manatee tracking project” album) and videos at www.youtube.com/user/GeorgiaWildlife.

Learn more online about DNR’s Nongame Conservation Section (www.georgiawildlife.com/conservation), Naval Submarine Base Kings Bay (www.navy.mil/local/subasekb), Georgia Aquarium (www.georgiaaquarium.org) and Sea to Shore Alliance (www.sea2shore.org).

IF YOU SEE A TAGGED MANATEE

Report the manatee to Georgia DNR by calling 1-800-2-SAVE-ME (800-272-8363). Note the time, date, location, color of the tag and whether any other manatees are present. Do not chase, touch or otherwise harass the manatee, or touch the tag. The tag is harmless to the animal.

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