Updated

Boaters and beachgoers in a Cape Cod town are getting some advice from authorities this holiday week after great white sharks were spotted in local waters: Stay away from seals.

A 12- to 15-foot shark was seen last week off Chatham. A state researcher says it was the first confirmed shark sighting of the season. Two more great white sightings were reported Tuesday.

The same waters are filled with seals, which draw the sharks because they are a favorite food of the animal.

Authorities have issued an advisory telling people to stay at least 300 feet away from any seals, so they don't run into their fearsome predator.

The town's harbormaster said Tuesday that Chatham isn't closing its beaches, just warning people to pay close attention to their surroundings and stay close to shore.