Mother, baby dolphin safely herded out of Nantucket Harbor

The dolphins were seen in shallow water, swimming inside the yacht club piers, with the likelihood of potentially stranding again very high.After being called to help two common dolphins on the island of Nantucket last Thursday, IFAW’s Marine Mammal Rescue & Research team successfully herded the dolphin pair out past the ferry entrance buoy into Nantucket Sound

The mother and calf were first observed swimming close to shore near the Great Harbor Yacht Club on Wednesday afternoon.

The team provided phone consultation with state environmental police officers about potential response options. Meanwhile, both dolphins partially stranded themselves in a nearby tidal marsh, but the officers were able to relocate them into deeper water in Nantucket Harbor.

Unfortunately, the following morning the dolphins were seen back in the same location, this time swimming inside the yacht club piers. With the likelihood of dolphins potentially stranding again, we headed over.

Once we boarded the ferry and began the one hour trip, the ship experienced a severe mechanical failure and had to immediately cancel the trip. Scrambling to find any other way to get team of six over to an island that is 26 miles off the southern coast of Cape Cod, we were able to procure a special chartered plane through Cape Air leaving Hyannis for the 20-minute flight over to the island.

We were able to procure a special chartered plane through Cape Air leaving Hyannis for the 20-minute flight over to the island.

With only about two hours of daylight to work with, some of us boarded a vessel to attempt to herd the free-swimming mom/calf pair out from near the pier into deeper water and the other members remained on shore as spotters and for land communication.

It was difficult at first trying to herd the dolphins away from the pier out into the greater harbor because of intense pile driving operations that were occurring at a nearby commercial pier. It appeared from their movements that both were very hesitant to swim out further into the harbor due to the likely intense underwater sounds emanating from the pier construction.

Upon request from the local police officer, the contractors working at the pier kindly ceased their pile driving operations, which almost immediately had a positive effect on the animals’ behavior. They were less cautious in their swimming patterns and much more responsive to the herding vessel by moving further out into the harbor on their own.

Once the pile-driving operations ceased, the dolphins were less cautious in their swimming patterns and much more responsive to the herding vessel by moving further out into the harbor on their own.

At 3:30 pm, we deployed a variable frequency acoustic device (called a pinger) to assist in the herding operations. Pingers are commonly used as herding tools in combination with vessel movement to move free-swimming dolphins out from near-shore locations into deeper waters.

Over the next hour, both dolphins responded very well to the herding procedures, sticking close together and swimming in coordinated movements out past the center of the harbor and through the ferry entrance to the island. Finally, at 4:41pm, with darkness approaching, the dolphin pair was successfully herded out into Nantucket Sound in approximately 30 feet of water ending our day with a happy moment.

While Nantucket is outside of IFAW’s normal stranding response area a special request for assistance was received from the National Marine Fisheries Service, the permitting agency for all marine mammal stranding work in the US.

This response was successful due to the collaborative efforts from multiple agencies and individuals, including Massachusetts Environmental Police (Sgt. Keith Robinson), Animal Control Officer -  Nantucket Police (Officer Suzie Gale), Shearwater Whale Watch Excursions (Capt. Blair Perkins), and the Nantucket Marine Mammal Conservation Program (Scott Leonard).

--CH

Learn more about IFAW's marine mammal rescue and research here.

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Experts

Brian Sharp, Emergency Relief Officer, Stranding Coordinator
Manager, Marine Mammal Rescue and Research
Dr. Maria (Masha) N. Vorontsova, Regional Director, Russia & CIS
Regional Director, Russia & CIS
Patrick Ramage, Program Director, Whales
Program Director, Marine Conservation