Chessie, the wandering Florida manatee that has visited the Chesapeake Bay at least twice over the past 17 years, is back. The well-traveled mammal has not been seen since 2001, and his resurfacing is making waves among marine scientists and bay folk alike.
"I wanted to let you know that the [U.S. Geological Survey] identified the manatee from Wednesday, and it's a familiar face to us … it's Chessie!," said Jennifer Dittmar, stranding coordinator for the National Aquarium, in an email to a Calvert Marine Museum staffer, confirming the animal's return.
The male "sea cow" was sighted Tuesday in a marina harbor in Calvert County, Dittmar said. Chessie spent about four hours around Flag Harbor Yacht Haven in St. Leonard before moving on, Dittmar said. There have been no sightings reported since then, she said.
"It came up about every 10 or 12 minutes for a breath and then just sank back down," said Hank Curtis, a resident of St. Leonard who's retired but works part time at Morgan State University's Estuarine Research Center in Calvert County. Curtis, whose photos were used to confirm the manatee as Chessie, said being one of the first people to see Chessie in about a decade is "really exciting."
Curtis' photos of Chessie on the water's surface were sent to biologists at the USGS for analysis, and they confirmed the gentle, slow-swimming creature's identity from distinctive markings on his body.
"Chessie has a very distinct scar, and that's how we were able to know it was him," said Cathy A. Beck, a wildlife biologist with the USGS who manages the organization's manatee database. The catalog has information on the "features," scars and other marks on an animal's body, of more than 2,500 manatees, she said.
This creature's distinct marking, on his left side, is a 12- to 18-inch-long gray scar with a white center that is between 1 and 2 inches in length, Beck said. The white part, she said, was probably a deeper part of the cut.
"Often, the more severe wounds don't repigment back with the color of the epidermis," Beck said. The scar was probably created by a boat's propeller, which is the most common way for manatees to be marked, she said, because they swim near the surface.
The USGS manatee database has been a work in progress since the 1960s, Beck said, and contains more than a quarter-million images of manatees. Biologists gather photographs of a manatee and, when most of the manatee's features are known, they are marked on a chart and each marking is coded so comparisons can be completed quickly, she said.
"Once we have all of the features we can see on an animal, we put them on a grid, sort of an outline of a flattened manatee," Beck said. Chessie also has a shorter scar that runs perpendicular to the long, bi-colored marking and several small nicks in his tail, she said. The perpendicular design of the two scars is common for manatees, Beck said, because of the shape of boat motors.
Chessie's first confirmed bay sighting was in 1994, when he was about 5 years old, Beck said. He lingered into the fall, prompting wildlife specialists who worried that worried he wouldn't survive the winter cold to mount an effort to return him to warmer water in Florida. After eluding would-be rescuers for more than a week, the manatee was captured near the mouth of Queenstown Creek and taken to the aquarium for nearly two weeks of rehabilitation before being flown back south.
It was during this containment, Beck said, that Chessie's markings were recorded. The year after his capture, Chessie swam even farther north, to New England, becoming the first confirmed manatee north of the Chesapeake.
Biologists fitted him with a radio transmitter to follow his movements, but they lost track of him in summer 1996 when a storm hit while he was in North Carolina waters. Chessie's last confirmed sighting was in August 2001 in Virginia.
Beck began to fear that Chessie had died. Manatees are considered endangered because of loss of habitat and dangers posed by human activities such as boating or hunting.
"We've had a couple really severe winters these past few years," said Beck, who is stationed in Gainesville, Fla., which is near where manatees congregate year-round, but in cold-weather months in particular. There have been many manatee fatalities, about 400 per year, because of the cold in the past two years, she said.
Manatees normally begin moving toward warmer water when the temperature reaches 68 degrees, Beck said. When water temperatures dip to 63 degrees or less, a manatee's life is in danger, she said, although, as with humans, manatees have individual tolerances for heat and cold.
Manatees can live up to 60 years, said Patrick Rose, an aquatic biologist and executive director of Save the Manatee Club. The average life span in the wild, though, is between eight and 11 years, he said.
Chessie has lived well beyond that average and is probably more than 20 years old, Beck said.
Beck wanted to be certain that the manatee seen recently was Chessie, she said, so she gathered six biologists to analyze the photos taken earlier this week against the database. And there's no doubt, Beck said, that Chessie has returned.
Manatee sightings have become an almost annual occurrence in recent years. A manatee nicknamed Ilya was sighted in the upper bay in 2009, and it was rescued that fall off the New Jersey coast. A manatee also was seen in Baltimore harbor last summer, and a dead manatee was found in April 2010 near the Calvert Marine Museum in Solomons.
But Beck said that no one can be sure if the number of reported sightings has increased because more manatees are swimming north or because people are more aware of manatees.
"They're pretty consistent," said Dittmar. "Usually in July is when we get our first sighting." Manatees are able to live in many areas, as long as the water is warm enough, because they eat many types of underwater plants and seagrasses.
According to the Maryland Department of Natural Resources, the surface water temperature this week in the part of the bay where Chessie was recently seen is in the high 70s to low 80s. The average temperature of the bay has increased between 1 and 2 degrees over about the past 25 years, said Bruce Michael, director of the DNR's Resource Assessment Service.
Gene Taylor, safety and risk manager for the National Aquarium in Baltimore, was deeply involved with Chessie's 1994 rescue. He is delighted that Chessie has returned.
"There was just a glow when I heard … that the animal was back," Taylor said. "There's a special feeling in my heart that the animal has made his way back to the Chesapeake Bay."
Beck, keeper of the nation's manatee database, wishes that if Chessie is seen again in the Chesapeake that people will respect him.
"I'm really hoping that if people sight him again, they'll take pictures but they'll leave him alone," she said. The pictures, Beck added, might be of use to her database: "We haven't seen the right side of his body in a while."