Group Of 20 Great White Sharks Sighted Off San Francisco Coastline

The U.S. Coast Guard has spotted an unusual grouping of great white sharks off the coast of California, as roughly 20 of the predatory fish were seen less than 100 yards away from shore.

The odd sighting took place on October 16, according to the LA Times, as a Coast Guard patrol flew over both Pacifica Pier and Ocean State Beach, located in San Francisco. The crew spotted the great white sharks, which measured between 10- to 18-feet long, noting both their size and proximity to shore. While the majority of the sharks measured less than 15-feet-long, several of the largest specimens were bigger, indicating that they are mature adult sharks.

Mary Jane Schramm, a spokeswoman for the Greater Farallones National Marine Sanctuary, noted that the smaller sharks were likely sub-adults. She pointed out that it is hardly unusual to see great white sharks hunting in the region at this time of the year, though a gathering of so many in the same place hasn’t been recorded in recent memory.

A warmer-than-average El Niño has been blamed for increased white shark sightings in Southern California over recent months. In other areas along the California coast, weather conditions have been blamed for odd sightings of fish, while whales have been observed moving into shallower water following their prey. Experts note that the sharks observed off San Francisco could be drawn to the area by whale carcasses, as earlier this year there were an unusual number of strandings reported. Both blue and sperm whales are known to inhabit the area.

David McGuire, Director of the San Francisco shark conservation group Shark Stewards, noted that photos of the sharks confirm they are indeed great whites (even though salmon sharks, which can resemble juvenile white sharks, are often found in the area during the fall). He pointed out that the sharks were distributed over a 12-mile-long stretch of coastline, and as such, the group would not normally be described as a “swarm” or “cluster.” In recent days, both terms have been used by multiple media outlets to refer to the great whites. Instead, McGuire noted that the sharks could be best described as gathering in a “loose aggregation.”

The presence of so many great white sharks has caused understandable concern among local beachgoers, though Schramm noted that surfers are aware that the animals frequent the area, generally speaking. Despite their presence, attacks on humans remain exceedingly rare in the region, though some experts advise caution among swimmers and surfers.

The grouping of sharks is not the first to be observed in the region this year. In early July, another aggregation of white sharks (mostly juveniles) was spotted off Aptos, also located in California. While white sharks don’t school, they do gather near feeding zones, such as the Farallon Islands. Juvenile sharks are more likely to approach the coast, while more mature specimens (who are also less likely to strike at humans) are inclined to remain further away.

The sighting comes just a few weeks after a sub-adult great white shark was filmed preying upon a seal or sea lion just off Alcatraz Island. Though such events are common along the coastline, this particular incident was noteworthy due to its occurrence within San Francisco Bay.

Shark Stewards have established the hashtag #Sharkwatch on Twitter so that beachgoers can alert each other to the animals’ presence if they are spotted. Operated in conjunction with the California Academy of Sciences, Shark Watch is a citizen science program that will record observations using the iNaturalist app, so that the movements of the local great white shark population can be tracked and better understood.

[Photo by Elias Levy – Own Work via Flickr | Cropped and Resized | CC BY 2.0]