The Chesapeake Bay has striped bass, sea nettles and blue crabs. But dolphins and whales?
Whale watching may never become a local tourist attraction, but marine mammals have suddenly begun appearing in the bay and along the Atlantic Coast in numbers that appear to be larger than expected.
The reason for this increase could be as simple as a telephone number. Within the past year, the Maryland Department of Natural Resources, the National Aquarium in Baltimore and the Smithsonian Institution have formed a network to keep track of marine mammals in the bay and along the Atlantic Coast. And they have a hot line, 1-800-628-9944, for people to call when they see whales or other mammals.
Since last fall, the network has documented sightings of numerous species of endangered or threatened marine mammals: harbor porpoises, striped dolphins, right whales, humpback whales, true's beaked whales, a short finned pilot whale and the Flipper-like bottlenose dolphin.
One of the most dramatic scenes occurred last May when 30 or 40 dolphins were spotted in the Choptank River by scientists at the University of Maryland's Horn Point Biological Laboratory near Cambridge on the Eastern Shore.
Then this fall, boaters and DNR police followed a whale for hours as it dove and surfaced in the Chesapeake Bay above the bay bridges. The whale was last seen heading out of the bay.
"Some people say they have not seen dolphins this high up in the bay. In two to three years, after we have better data, we can tell you, 'Yes, we are seeing more of this.' But in this time frame, it is kind of iffy," said Eric B. May, coordinator of the DNR's fish disease program.
However, Dr. May said, if there are more mammals swimming in the bay's shallow waters, they may be attracted by slightly warmer temperatures as they migrate south. The warm waters also increase the amount of plant material for some whales to eat, he said. And finally, dry weather increases the salinity of water, another factor that could draw mammals into the bay waters.
But all of that is pure speculation, he said. Right now, researchers such as Cindy Driscoll, a veterinarian with the DNR, are just trying to keep up with the number of sightings and the number of animals that die and wash ashore.
Dr. Driscoll does necropsies, or marine mammal autopsies. Her work will be important in documenting whether chemical pollutants or unusual diseases could be factors in the deaths of the marine mammals. So far, Dr. Driscoll said, the stranding network has not seen anything unusual.
Experts look forward to having reliable information about the travels of marine mammals from the new network, said Colleen Coogan, the National Marine Fisheries Service stranding network coordinator for the northeast region.
The data will be used in helping to evaluate whether projects, such as the dumping of sludge or drilling for oil, might affect a marine mammal population.
In addition, the network will come to the rescue of mammals that are stranded.