Famous Manatee "Chessie" Sighted in Chesapeake Bay After Long Absence
A manatee spotted in mid-July in Calvert County, Maryland, is the same one that first made waves 17 years ago when he appeared in Chesapeake Bay just before the onset of winter and later had to be rescued.
The identity of the manatee, known as "Chessie," was verified by U.S. Geological Survey (USGS) biologist Cathy Beck, who matched photographs taken July 12 with Chessie's photographic record in a USGS manatee database. Chessie's telltale markings include a long, gray scar on his left side.
USGS scientists regularly document manatee sightings to analyze the life histories of individuals as part of an ongoing effort to estimate adult survival rates of the endangered Florida manatee. Yet biologists were surprised to find that the animal sighted in July was Chessie, a well-known manatee who had not been seen for about 10 years. The last time USGS researchers confirmed a sighting of Chessie was after he swam through Great Bridge Locks in Virginia on August 30, 2001 (details at http://fl.biology.usgs.gov/Manatees/Manatee_Sirenia_Project/
By then, Chessie was already well known. After Chessie was found in the Kent Narrows area of the Chesapeake Bay in the fall of 1994, researchers became concerned about how he would fare during the oncoming winter. Manatees suffer negative health effects when they endure water temperatures below 68°F for any length of time. With water temperatures dropping in the bay, the Marine Animal Rescue Program at the National Aquarium worked with the U.S. Fish and Wildlife Service, Seaworld Orlando, and the Maryland Department of Natural Resources to rescue Chessie. He was cared for at the aquarium for several days before being successfully flown back to Florida and released.
The summer sighting did not drive any plans to rescue Chessie because the water was still warm and manatees typically work their way back down the eastern seaboard to Florida on their own when cooler weather sets in.
Scientists are not sure whether Chessie visits the Chesapeake Bay every year. After Chessie's 1994 rescue, USGS scientists tagged him and found that he did migrate back to Chesapeake Bay the following spring. (That tag and a second radio transmitter fell off; Chessie is not currently tagged.) Much of what scientists know about manatee migration comes from studies that use radio and satellite tags to reveal key facts about manatees' habitat needs, such as how they use seagrasses and winter refuges.
In general, scientists believe manatee migration from Florida to the Chesapeake Bay may not be unusual, and, in fact, Chessie was named after legendary sightings of a "sea monster" in the Chesapeake Bay throughout the 20th century.
Chessie was spotted and identified this year thanks to the help of two bystanders who took pictures of him and contacted Jennifer Dittmar, the National Aquarium's Coordinator for the Northeast Marine Mammal Stranding Network. Dittmar forwarded Beck photographs of the manatee's head and back.
The public is urged to report all possible sightings of a manatee in Maryland waters to the National Aquarium's Stranding Hotline at 410-373-0083 and to send photographic images to firstname.lastname@example.org.
Read more about Chessie and how manatees are identified in "Manatee Traveler in Northeastern Waters Not Chessie," Sound Waves, September 2006. A history of Chessie sightings is posted at http://fl.biology.usgs.gov/Manatees/Manatee_Sirenia_Project/Manatee_Chessie_Surfaces/manatee_chessie_surfaces.html. For additional information about manatee biology, visit the USGS Sirenia Project's Web site at http://fl.biology.usgs.gov/Manatees/manatees.html.
in this issue:
Manatee "Chessie" Sighted in Chesapeake Bay