Nearby waters a white shark hot spot | Inquirer and Mirror – The Inquirer and Mirror

(Aug. 3, 2023) The first ever scientific estimate of white shark abundance in the waters off Cape Cod shows its not just a habitat, its a hot spot.

The study, led by the Atlantic White Shark Conservancy, estimated that 800 individual white sharks cruised through the waters from 2015 to 2018.

We knew there were a lot of white sharks here, but to see that it compares with some of the largest white shark hot spots in the world was a surprise, said Megan Winton, the studys lead author.

From a conservation perspective it was really good news. The species in the western North Atlantic was knocked down really hard in the sixties and seventies and its a conservation success story to see them coming back.

The study used video tags to collect nearly 3,000 videos of 393 individual white sharks which helped identify individual sharks based on markings and notches on their dorsal fins, but it also allowed researchers to witness hours of footage of the elusive sharks.

One thing is very clear to Winton: many of the white sharks are here to feed on seals, spending almost half their time in waters 15 feet deep or less. They look to position themselves between the seals on land and the nearby fish that the seals need to get to.

While this might sound scary given its the same shallow waters people are swimming in during the summer, its also a testament to how efficient white sharks are as hunters, Winton said.

Shark attacks on humans are extremely rare. The University of Florida listed the odds of dying of a shark attack in the United States at 1 in 264.1 million.

The camera tag footage has been really enlightening, Winton said. Weve seen instances of sharks investigating things (birds onthe surface, lobster buoys). Theyre very curious animals, theyre also cautious animals. Theyre not these eating machines out there just biting stuff all the time.

The study tagged hundreds of white sharks over a four-year period, and although Nantucket was outside of the studys tagging zones, many of the tags ended up around the island, Winton said. Great Point is a known seal and white shark hot spot. Given the abundance of both in the area the Trustees closed the beaches in the area to swimming this summer.

The tags come up to the surface when they detach from a shark and we have to go physically recover them, Winton said. Many of those tags wed have to pick up off the coast of Nantucket. Part of that is currents, but we know that the sharks move down there and they move all around.

The study also showed there is a lot of turnover in the white sharks that do visit Cape Cod in the summer. Just like people, there are some that visit every summer, like a white shark researchers dubbed Mr. Frisky, while others just make a quick pit stop.

Mr. Frisky, (yes Winton acknowledged, they have some goofy nicknames for the sharks) has been a regular around the Cape every summer since 2017, but last summer they didnt see him or getany pings from his tag. They worried it might have been the end of Mr. Frisky. But then they got a message from some of their collaborators in Canada that Mr. Friskys tag had been pinging up there all summer.

We had some sharks that we had long thought of as our resident sharks, that we would see every summer, she said. And theres also a lot of sharks that are just these kind of transient sharks, that pass through the area, stop and get a snack (a seal) and move on. But what we see now is that there seems to be a shift in our resident sharks after a period of a few years.

According to the data from the study, the white shark population around the Cape reaches its peak from late August to early October. They also noted that the number of white sharks increased yearly throughout the study, with the largest numbers coming in the final year.

The study, An open spatial capture-recapture framework for estimating the abundance and seasonal dynamics of white sharks at aggregation sites was published in the journalMarine Ecology Progress SeriesJuly 27. It included scientists from the Atlantic White Shark Conservancy as well as UMass Dartmouths School for Marine Science and Technology and the Massachusetts Division of Marine Fisheries.

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Nearby waters a white shark hot spot | Inquirer and Mirror - The Inquirer and Mirror