CHATHAM – The sighting of an injured and bleeding seal, apparently a recent victim of a shark attack, prompted the closure of Lighthouse Beach to swimming on Sunday.
The beach was closed for about two hours while harbor patrol and park department staff searched the waters immediately adjacent to the popular beach. Harbormaster Stuart Smith said the seal was later seen along the shore, apparently alive but with bite marks on its body, but no shark was sighted. The seal's fate was uncertain.
The beach was reopened about 3:45 p.m., said Park and Recreation Director Dan Tobin. Even though there was no first-hand observation of a shark, the presence of the injured seal led to a “reasonable assumption” that a shark could be in the vicinity, he added.
An alert was put out on the Atlantic White Shark Conservancy's Sharktivity app after the beach was closed.
“The system seemed to work well,” Tobin said. “The public was very cooperative and seemed to understand the nature of the situation.”
The seal was sighted by crew members on commercial fisherman Jim Nash's boat, Smith said. There was blood in the water and it appeared that the seal had “just been hit. They said it was pretty impressive.” He wasn't sure if they had seen a shark as well; attempts to contact Nash were unsuccessful.
The injured seal was seen just south of the Lighthouse Beach swimming area, around buoys 2 and 3, said Smith.
“I'm a little surprised it got over the bar,” Smith said of a shark being inside the harbor. Depth on the bar can be as little as four or five feet, he added.
While there was no confirmed sighting of a shark, if the seal was attacked at that location it's the first time one of the predators has been inside the harbor in two years. Atlantic White Shark Conservancy Executive Director Cynthia Wigren said a receiver buoy inside the harbor is checked twice weekly and as yet there have been no detections this season, but two years ago a receiver buoy inside the harbor did detect a shark, Smith recalled.
With that knowledge, “We'll be a little bit more wary,” Tobin said.
The beach was crowded – but not overly so – at the time of the incident, and as soon as the harbormaster informed the beach patrol, the red flag went up to signal no swimming and those in the water were told to come ashore. Tobin said it was “almost too hot” on the beach Sunday, and after the warning went up, many people left.
The sighting was “not completely unexpected,” and comes at the time of year when shark activity usually ramps up, Tobin said. This year, however, shark sightings began earlier than usual. The Atlantic White Shark Conservancy-funded research trips by the state division of marine fisheries have tagged 10 white sharks this season, and observed and identified dozens more. Scientists are in the third year of a five-year population study of the region's great white sharks.