Great white sharks do not look maternal.
With jaws like a vise, beady, obsidian eyes, and torpedo-shaped bodies, these predators seem far more menacing than motherly. But what if we found evidence to suggest otherwise?
For the first time, biologists have located a great white “nursery,” where mother sharks deliver pups, alive and fully formed. Researchers with OCEARCH, an ocean research nonprofit, identified the site this week in waters off Montauk, Long Island.
This monumental finding is “probably the most significant discovery we’ve ever made on the ocean,” said Chris Fischer, the founding chairman of OCEARCH. In an interview with CBS News, Fischer noted that great white birthing sites are regarded as “the holy grail of research,” and are especially important in the Atlantic Ocean, where the sharks are vulnerable to bycatch and sport fishing.
Image: Flickr/Brook Ward
It took OCEARCH 26 expeditions to find the nursery, which called on the efforts of both scientists and fishermen. Once they discovered its whereabouts, the crew tagged nine sharks in less than a week—a rarity, as some researchers can spend their entire careers without spotting even a single great white. Since then, multiple sharks have been captured and released by OCEARCH in a single day.
Atlantic great whites tend to summer in the north, and spend their winters down south, but at any given time, they could be everywhere. When the team noticed that most of their catches were juveniles and pups, however, they knew that these weren’t just rogue wanderers. At some point, they realized mama was here.
OCEARCH has helped to pioneer the field of great white tracking, and currently monitors several dozen individual sharks throughout global waters. By outfitting them with special dorsal fin tags, scientists are able to follow the sharks in real time, for up to a decade. The tagging process takes about 10 minutes, during which the shark’s gills are flushed with water. Using a power drill, a remote tracking sensor is fastened to their fin. If you’re concerned that this hurts the sharks, Fisher says not to worry—if it did, they wouldn’t be doing it.
“The strategy at the time was to get a tag out on big mature animals, and when you get one on a big female, 18 months later, she should lead you to… the birthing site,” said Fischer.
Researchers are eager to determine whether any of the young sharks captured in Montauk are the offspring of individuals tagged near Cape Cod. According to Haley Newton, a veterinary pathologist with the Wildlife Conservation Society who has been working on the expedition, juvenile great whites are vastly understudied, simply because they’re so difficult to find. Earlier this year, scientists with the Long Island Shark Collaboration managed to tag the first ever great white pup in the Atlantic Ocean.
Despite being the most infamous predator in the sea, great whites are disproportionately mysterious. No one has witnessed a female giving birth, and biologists aren’t sure what their mating behavior entails. Great whites are known to migrate in tangents, but what compels them to wander for thousands of miles remains speculative.
Every winter, great whites inexplicably gather near a spot called the “white shark café,” somewhere between Mexico and Hawaii in the Pacific Ocean. Scientists have no idea what’s so special about this location, but they know that here male sharks will dive up to 200 meters deep, as many as 150 times per day—behavior that’s considered abnormal for great whites. In 2017, a crew from the Monterey Bay Aquarium plans to record the sharks’ activity using custom-made “swimming robots.”
The data collected by OCEARCH will hopefully reveal new insights about great white life stages, especially those of young pups. In addition to tracking their locations, scientists will be analyzing blood and parasite samples collected from the sharks. Ultimately, their findings will help to inform conservation decisions in the Atlantic Ocean, where great white populations are estimated to have declined by 75 percent in the last 15 years.
Worldwide, the total number of sharks killed by humans every year has skyrocketed to 100 million, due to threats such as finning, bycatch, sport fishing, and habitat destruction.
Thankfully, organizations like OCEARCH are not only directly contributing to shark science, but are also making the public aware of the animal’s conservation status.
Their most notable research subject is a 16-foot female, affectionately named “Mary Lee,” after Fischer’s own mother. Weighing in at 3,400 pounds, she was last seen off the coast of South Carolina, and has traveled more than 34,000 miles since being tagged. She even has her own Twitter account, which may not help to dispel the myth about sharks loving the internet.
If you’re feeling curious, all of the sharks tagged off Long Island are now pinging their locations to OCEARCH’s live-tracker. Where, exactly, will “Hampton,” “Montauk,” and the others go? That’s for you to find out.
from Newly Discovered Great White Nursery Is 'Holy Grail' of Shark Research