A pack of 20 great white sharks have been spotted swimming off the California coast, a mere 100 yards from the city of Pacifica, a popular tourism and, more worryingly, marine sports destination. U.S. Coast Guard helicopters flying at 500 feet above the water spotted the sharks on Saturday. The sighting has amazed shark experts and conservationists, who say that such an aggregation of great white sharks near an urban area is unprecedented. Others are less enthusiastic, citing concerns about the safety of swimmers and kayakers in the area.
Great white sharks can grow up to 20 feet in length and weigh in at about 7,000 pounds. According to the San Francisco Chronicle, these great whites were between 10 and 15 feet long, with “a couple” of monsters at 18 feet. This would mean a group of well and truly mature great white sharks, something which has, according to USCG Lt Beau Belanger, never been seen so close to a human population center. Unseasonably warm waters have seen larger than usual groups of juvenile great white sharks collecting up and down the coast, but this pack of adults is another phenomenon entirely. Mary Jane Schramm, a spokesperson for the Gulf of the Farallones National Marine Sanctuary, confirmed that the sighting was an unusual one.
“This is the first I’d heard of near-shore aggregating in such an urban area.”
Why are they coming inshore? Great white sharks are usually found off the Farallon Islands, from which point they tend to head to deep water to feed. This year, instead of going West to search for prey, these particular sharks appear to have travelled east toward San Francisco and Pacifica. Some experts are speculating that the El Nino weather system may have warmed coastal waters enough to throw the massive sharks off their ordinary beaten paths. There has been an increased frequency of shark sightings all over the world, and the waters off Alcatraz have recorded up to 20 great white sharks by a tagging program.
It’s important to keep perspective, though. Sharks, particularly great white sharks, have a very low incidence of attacking humans. The number of shark fatalities is still very, very low, with more people dying from taking selfies than from shark attacks. Great white sharks prefer seals as a source of food and are well known for being quite picky about their diets. In fact, apart from a couple of more aggressive species, most sharks appear to have a real aversion for the taste of human.
In Australia, where sharks of all kinds abound, there is a great deal of advice about how to avoid shark attacks. Key among the proposed reasons for great white shark attacks is being mistaken for a seal. Surfing and bodyboarding while wearing a wetsuit seems, in the opinion of many experts, to imitate, from a shark’s eye view, the behaviour of their favorite prey. The speeds at which people skim across the water when pursuing these and other marine sports seems to trigger an attack mechanism in great white sharks. Even this, however, doesn’t guarantee an attack. Great white sharks have been photographed and filmed closely observing divers and surfers without really showing any inclination to remove their limbs.
While the best way to guarantee safety from shark attacks is to stay on land, there is still no reason to swear off ocean swimming forever. David McGuire, director of Shark Stewards, said that there was no reason to panic. He indicated that swimming and surfing off Pacifica might not be the best idea for the next few days, and the sighting should not discourage people from enjoying the ocean.
[Photo by Getty Images/Dan Kitwood]