Nantucket adopts shark sighting policy after false report

28. July 2012

Nantucket selectmen have endorsed a new beach policy after a supposed shark sighting July 18 at Fisherman’s Beach turned out to be a false alarm.

The shark scare briefly closed three popular south shore beaches to swimming, but the sighting was actually an ocean sunfish, or mola mola, John Chisholm, of the Massachusetts Marine Fisheries’ shark-research program, said this week. On Wednesday, the board of selectmen unanimously approved a new policy “regarding shark sightings at lifeguarded beaches.”

The policy was implemented at the request of the town administration, the police and the harbormaster’s office. Nantucket officials consulted with the Cape Cod National Seashore and the town of Chatham on the wording.

Board of Selectmen Agenda – 07/25/2012



The numbers of shark sightings on outer Cape Cod has increased dramatically over recent years due to the growing seal population. These sightings have created increased local and national news media coverage.

Occasionally, sharks are observed from the shoreline of Nantucket beaches. It can be difficult to determine the species of the shark. Often times basking sun fish are observed and thought to be a shark by persons on the beach. The difference is that a shark’s dorsal fin cuts through the water in a straight line; is constantly moving and normally a shark’s tail fin is exposed also.

Experts say that people can avoid encounters with sharks by staying out of the water between dusk and dawn; staying in groups whenever possible; not swimming in sight of observed seals and not venturing too far from shore. Lifeguards are responsible to educate the beachgoer about safety to avoid encountering shark and other marine mammals. Public education will be through outreach to the beachgoers and swimmers and posting Local Notice to Mariners and Swimmers from the Department of Public Safety Marine Division.

If a shark is sighted, lifeguards will take the following action for the safety of the people at the beach:

1. Determine the size of the shark. If the shark is less than 4 feet in length (sand shark or dogfish) there is no reason to get people out of the water.

2. Assess the shark’s behavior. If the shark is feeding, stalking or has otherwise peculiar behavior, a closure is indicated regardless of size.

If a closure is initiated, the closure will be terminated two hours after the last observation of the shark if the shark is inside of the swimming area. If the shark is outside the swimming area, the closure will be terminated one hour after the last observation. Only confirmed sightings warrant a closure of the beach to water activities. Only sightings from reliable sources (Lifeguards, ATV operators, Nantucket Police, Nantucket Fire or sources deemed reliable by Marine Division Supervisors) will be considered verified and confirmed.

Once a sighting has been confirmed, the Lifeguards will:

1. Contact Police Dispatch on Marine 1. Advise Police Dispatch which direction the shark is heading; how far off shore it is; and approximate size if known.

2. Clear the water on the protected beach and fly a double red flag.

3. Proceed to adjacent unprotected beaches and advise the beachgoers and swimmers on those beaches.

4. Keep the water clear for one hour if outside the safe swim zone and two hours if inside the zone.

5. Check availability of an aerial marine survey team to complete a flyover of the area.

6. Contact Police dispatch once the closure has been terminated.

 Sources: Town and County of Nantucket, Cape Cod Times.


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