The beachgoers who throng the sand of Long Island, New York, might be surprised to learn they aren’t the only ones who find these temperate waters the perfect place to swim and picnic..
Just offshore, in an area known as the New York Bight, hundreds of baby great white sharks figure out how to feed, navigate, and evade predators in what researchers now believe to be the North Atlantic’s primary—and probably only—great white shark nursery.
The North Atlantic population of great whites, once near extinction due to overfishing, has risen in recent years due to the resurgence of their prey, the gray seal. It’s now estimated to number around 800.
“As far as we know, the Long Island shark nursery is where all baby [great white] sharks in the North Atlantic spend their first year of life,” says Megan Winton, a research scientist with the Atlantic White Shark Conservancy, a nonprofit based in Massachusetts.
Watch the scientists catch the baby shark, Liberty, and equip her with a camera tag.
“And it just happens to be near one of the most densely populated areas of the U.S. coastline.”
Shark scientists have posited the existence of a white shark nursery off Long Island since the mid-1980s, Winton says, but only in recent years has hard data confirmed its existence.
Now, as part of the ongoing research project, Winton and her colleagues mounted a specially designed camera tag on a young female shark—dubbed Liberty after the New York City landmark—allowing them to track and experience a baby shark’s movements for the first time ever.
Understanding baby-shark movements is also critical to protecting them, as it’s these very same sharks that eventually move north to inhabit the waters off Cape Cod, which a study last year, co-led by Winton, determined likely has the highest density of great white sharks in the world.
SharkFest kicks off June 30 with the show Shark Beach with Anthony Mackie: Gulf Coast at 9/8c followed by Shark Vs. Ross Edgley at 10/9c on Nat Geo. All SharkFest programming, including the episode Baby Sharks in the City, streams on Disney+ and Hulu July 1.
“We know virtually nothing about baby white sharks,” Winton says. “We know that they’re abandoned at birth, that they haven’t ever hunted before, they haven’t navigated these waters, so how do they survive? It’s really uncharted territory as far as white shark science goes.”
Seeing the months-old Liberty close up while the team carefully placed her satellite tag was a moving experience for Winton, who is part of the Nat Geo SharkFest episode Baby Sharks in the City.
“I can’t believe how emotional I got,” she says. “She was so beautiful, like a perfect mini version of an adult white shark.”
Where does a baby shark go?
Several research institutions and agencies have conducted annual expeditions using acoustic and satellite tags to follow the movements of Long Island’s young sharks.
While no one has ever seen a white shark give birth, the fact that they show up every year in May and June in such numbers suggested they’re born nearby, says Tobey Curtis, a fishery management specialist with NOAA’s Office of Sustainable Fisheries who co-authored several studies on the nursery.
Research has revealed baby sharks spend almost all their time within the nursery: More than 90 percent of them remain within 12 miles of the shore, swimming parallel to the eastern Long Island coastline.
Scientists believe the nursery, located in a triangular area between Montauk Point, Long Island; Cape May, New Jersey; and New York City, could produce up to 200 great whites a year. (Want to see great whites? Consider Cape Cod.)
Through the camera tag’s minute-by-minute record of Liberty’s activities, the researchers found further proof of the nursery’s importance as a sheltering habitat. Ten hours of footage revealed the young animal’s habits, such as diving for squid up to 150 feet deep, then moving closer to shore to feast on huge schools of bunker fish, also known as menhaden.
Her movements also confirmed the researchers’ theory that baby sharks, not yet able to regulate their body temperature, prefer warmer temperatures, staying in the range of 70 degrees Fahrenheit as much as possible.
This warm environment is also free of many large predators yet rich in prey, particularly fish and squid that flock to the many shipwrecks scattered around Long Island.
Shark’s-eye view
While Liberty is the first baby shark equipped with a camera tag, the technology has been used to study adult white sharks in California and Cape Cod.
“We’ve deployed more than 30 of the cameras on adult white sharks and it’s just been an explosion in technology that really is opening doors to what we’re learning at an amazing pace,” says Greg Skomal, senior fisheries scientist with the Massachusetts Division of Marine Fisheries and part of the research team who studies Cape Cod sharks. (See more photos of great whites.)
“Camera tagging is unique in that you really get the shark’s-eye view of its environment,” adds Curtis.
“We can track them with different types of electronic tags and put dots on a map, but we can’t see what the shark sees. The camera allows you to see what kind of prey they might be chasing, what kind of habitat they’re swimming in, and if they’re interacting with other sharks or other animals in the environment, so it gives you that extra insight that you really can’t get from any other type of technology.”
Born ready
Great white shark motherhood has long been a mystery. No one has ever seen a white shark mate or give birth, though in January 2024 researchers in California shared what they believe to be the first ever images of a newborn shark just after birth, captured by drone.
Mothers carry a litter of between two to 17 pups for 18 months, giving birth when the pups are up to five feet long. “To carry that many four-to-five-foot-long baby white sharks, you’ve got to be big,” as Winton says.
That’s why female sharks don’t give birth until they reach a length of 15 feet or more, at which point they’re at least 30 years old. While pregnant, females continue to produce unfertilized eggs, which becomes food for their pups in utero. (Learn why great whites are still a mystery to us.)
“Female white sharks carry around all these very big babies for as long as they do to make sure they’re ready to rock as soon as they’re born,” Winton says.
“They’ve got all the equipment and they’ve got the teeth to go along with it, so they’re still pretty formidable predators in their own right.”
Warming waters
Tracking North Atlantic sharks’ movements also allows the team to monitor climate change effects, Curtis says. Along the northeastern U.S coastline, ocean temperatures have rose by 0.06 Fahrenheit between 1982 to 2016, and are predicted to warm faster than other ocean environments, according to climate research.
If warming waters cause the nursery to shift too far to the east and north, Curtis says, the baby sharks will be pushed into the hunting grounds of adult great whites, makos, and other shark species.(Read how to be safe while swimming in shark habitat.)
These shifts also change sharks’ relationship to prey, sometimes forcing them to change their diets in ways that may not be healthy. In California, for example, juvenile white sharks have moved north to the central coast, where they attempt to feed on otters, an unfulfilling food source.
“Climate change is definitely having an effect on the distribution of these animals,” says Taylor Chapple, assistant professor at Oregon State University and the first researcher to use camera tagging in his studies of California white sharks.
“Having this data gives us baseline information about what the animals are doing now, but also about how they’re moving in response to climate change.”
For instance, knowing that white sharks may follow their prey could help conserve the species, which the International Union for Conservation of Nature lists as vulnerable to extinction.
Liberty’s legacy
Despite such threats, the growing white shark nursery off Long Island can also be seen as a conservation success story, Curtis says.
“It’s amazing that the ocean is healthy enough to have these abundant fish populations, including abundant shark populations, right outside New York City and Long Island. Even with all those millions of people near the shore and the impact on the waterways, the ecosystem is healthier now than it’s been in a long time.”
As for Liberty, her tag fell off and floated to the surface as planned after 11 days.But hopefully itʻs not the last time researchers will see her, either in the nursery or off Cape Cod; Liberty has distinctive white markings on her tail and sides and has now joined the catalog of the more than 700 sharks in the Cape Cod database.
Plans are already underway for another camera-tagging expedition later this summer, Winton says.
“People don’t think of New York as a very wild place, but it’s so important” to many species, she says. “Tagging Liberty is just the start, and I’m just so excited to see where this research takes our understanding.”
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