Scientists lose touch with Chessie Wandering manatee is separated from tracking transmitter

Chessie is missing.

The wandering Florida manatee, who made news with his summer ventures into the Chesapeake Bay in 1994 and to Rhode Island waters in 1995, has been separated from the radio transmitter used to track his movements.


Scientists following the signal by satellite detected the separation July 10, when Chessie was north of Morehead City, N.C., near Pamlico Sound. Two days later, the region was swept by Hurricane Bertha.

Tuesday, biologist Jim Reid of the National Biological Service's Sirenia Project traced the transmitter's continuing signal to the Intracoastal Waterway near the Neuse River in North Carolina. He recovered the transmitter but found no trace of Chessie.


Wildlife officials say the storm's 100-mph-plus winds and tidal surge should have posed no serious threat to the manatee.

"There is no cause for alarm," said Linda L. Taylor, a spokeswoman for the U.S. Fish and Wildlife Service's Chesapeake Bay office. "He's familiar with tropical storms. They are tropical animals."

"Finding the transmitter without Chessie is a good sign," Taylor said.

The tether is designed to break under a strain of 100 pounds or more to protect the animal in case the device becomes caught on a pier or a sunken snag, something that has happened with Chessie twice before.

Chessie has not been sighted since the storm, and authorities are asking people from the Carolinas northward to the Chesapeake Bay and New England to watch for him.

Anyone spotting a manatee is asked to report details of the sighting to the National Biological Service in Gainesville, Fla., at (352) 372-2571; the National Marine Fisheries Service in Silver Spring at (301) 713-2289; or the National Aquarium in Baltimore at (410) 576-8723.

Chessie's radio transmitter was attached with a 6-foot-long plastic tether that is designed to bob to the surface and transmit whenever the manatee stops swimming. The signal reveals the animal's position and its diving and swimming activity.

Reid said the information is relayed to scientists by one of the National Oceanographic and Atmospheric Administration's polar-orbiting weather satellites if one is passing overhead when the transmitter surfaces.


Chessie left the St. Johns River in northern Florida early last month after being pronounced healthy and fitted with a fresh transmitter. He had been heading north, traveling 10 to 20 miles a day along the Intracoastal Waterway.

Satellite data indicated that he passed the Florida-Georgia border June 12 and Charleston, S.C., on June 24, pausing to join other manatees to feed on marsh grasses near Brunswick and Savannah, Ga.

By July 2, he had reached North Carolina waters, putting him about 10 days behind the pace he had set during last year's migration.

On July 10, the signal indicated that the transmitter had stopped moving. That meant that the manatee was dead or that he had pulled free of the radio's tether. The hurricane passed through two days later.

The manatee is part of a research and tracking project designed to gather data on the endangered mammals' range and habitat.

Chessie's September 1994 visit to the Chesapeake was cut short by scientists who feared that the bay's cool autumn waters would kill him. He was captured and flown back to Florida.


Last summer, humans left him alone, and he swam back to Florida from Rhode Island on his own, reaching Jacksonville by ++ mid-November.

Chessie apparently escaped the often fatal illness that swept through Florida's manatee population this spring.

Caused by brevetoxin, a poison produced by a micro-organism known as red tide, it killed at least 158 of the state's estimated 1,800 manatees.

European explorers reported manatees in the Chesapeake in the 1500s, but Chessie's visit in 1994 was the first such visit documented in modern times. It suggested to scientists that such annual migrations may once have been common.

The scientists also have surmised that reports of a "sea monster" -- also dubbed "Chessie" -- in the Chesapeake throughout this century may actually have been sightings of manatees that were never properly identified.

Pub Date: 7/19/96