A state veterinarian plans to use a variation of fingerprinting in an attempt to identify a whale that has been hanging around the Chesapeake Bay Bridge as one of a group of humpback whales that have spent several months in southern Virginia waters.
Dr. Cindy Driscoll of the Department of Natural Resources said she is gathering photographs of the 35-foot whale that has been seen near the bridge this week. She will send the photographs to the Virginia Marine Science Museum in Virginia Beach, Va., where scientists have been monitoring and photographing at least eight humpbacks.
Dr. Driscoll, the Maryland coordinator for a regional marine mammal stranding network, yesterday confirmed that the whale that has been swimming near the bridge is a humpback.
The species is known as the most acrobatic of the large whales.
The fingerprinting technique has been used for years by scientists in New England who track humpbacks in the waters off Cape Cod and elsewhere. Extensive photographic catalogs of the animals have enabled scientists to follow individual humpbacks year after year.
Each humpback has a distinctive black and white color pattern on the underside of its fluke, or tail. The animals also can be identified by other markings, including nicks or color patterns on dorsal fins or flippers.
Dr. Driscoll and other officials say they hope the detective work can add a page to the rather slim book of biological information about large whales in Maryland and Virginia waters.
She said she also wants to determine whether the whale in the bay has been photographed in New England waters.
"We don't have a great handle on the number and distribution of these animals," said Mark Swingle, an assistant curator at the Virginia museum.
He and colleagues believe that the humpbacks off Virginia, which have appeared for three winters in a row near the mouth of the bay, are part of an Atlantic stock that migrates in spring to New England waters and farther north.
He said scientists believe the whales in Virginia have found a consistent source of food at the bay's mouth. Large whales also are attracted to the Cape Cod area because the nutrient-rich waters there support large numbers of fish and crustaceans.