Great whites are among the most famous (and in diving circles, the most loved) of all the world’s marine animals. Yet we know relatively little about their lives, largely including when and where they are born. We do know that they can travel incredible distances, which is perhaps one reason why their movements are so hard to study. Great white breeding habits are especially enigmatic, as researchers only know about a handful of nurseries thus far. In addition to ones in South Africa and Australia, scientists think they have just discovered the first great white shark nursery in the North Atlantic, improbably located in the shadow of New York City.
Great White Shark Nursery Discovered
The great white shark nursery discovered in New York is centered in the waters directly off Long Island. An expedition that included scientists from a number of different organizations discovered the location. Among them were representatives from OCEARCH (famous for their white-shark tagging program), NOAA Fisheries, and the Wildlife Conservation Society. The team focused its search around Long Island after scouring North Atlantic great-white sighting records dating back 200 years. In doing so, they discovered that the Long Island area was the only one with consistent sightings of juvenile white sharks. And so, they launched an expedition to tag and research the young sharks.
Project participants were able to tag nine white-shark pups. This lead the scientists to declare the Long Island area the first known great-white nursery in the North Atlantic. According to OCEARCH founder Chris Fischer, the discovery is the most significant his organization has ever made. OCEARCH has led around 26 expeditions to tag great whites all over the world. The hope, among other things, was to learn more about the species’ reproductive habits. As well as tagging the sharks, the team weighs and measures them before taking a blood sample and a muscle biopsy.
Tagging Great Whites
The entire tagging process takes around 15 minutes. However, OCEARCH has come under fire from other conservation groups, which claim that their methods are damaging the sharks. In particular, they’ve expressed concern that the process of attaching the tag to the shark’s dorsal fin causes long-term fin degradation. Fischer, however, claims that the damage is minimal, telling CBS that “the fact of the matter is that we have to get some tracking devices on a handful of these animals so we can help them all thrive.” Tobey Curtis, the lead scientist at NOAA Fisheries agrees, saying that “tagging these baby white sharks will help us better understand how essential Long Island waters are for their survival.”
Scientists don’t know why the white sharks use Long Island as a nursery, but they think a combination of factors may be in play. The region is close enough to the continental shelf to allow easy access for adult white sharks. Pups take advantage of the protection in the area’s shallow bays. An abundance of food is nearby. These favorable conditions make it likely that the area is also a great-white birthing site, although scientists have not confirmed. The team hypothesizes that the pups might spend the first two decades of their lives in the New York area. Future monitoring will help prove (or disprove) this hypothesis.
The tag sends a signal whenever the shark’s dorsal breaks the surface, allowing the OCEARCH team to track its movements. For the scientists, the exciting part comes next. Until now, scientists based their knowledge about the area’s juvenile white sharks on conjecture. But with area sharks now sporting tags, the team hopes that new data will inspire better protective legislation for great whites in the North Atlantic. Those who want to follow the pups’ movements can do so on the OCEARCH website. The organization has logged the new additions under names like Montauk, Hudson and Manhattan.
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