Occasionally People Get Bit by White Sharks- What is your Relative Risk?

“Shark bites surfer” These news stories get more hits than Barry Bonds. As the press says, “if it bleeds it leads.”

If you surf, dive or recreate in the water in the Red Triangle– the area bounded by Big Sur, the Farallon Islands and Point Arena, the odds are much greater that you will encounter a large white shark. Most observations, bumps and bites occur south of Point Conception where mature females gestate and pup in the warm waters of Southern California. Most of the white shark observations in California tend to be in shallow waters and are young of year and juvenile sharks. Although the white shark population in the Northeast Pacific is increasing, in California the odds of a fatal encounter have statistically declined.

Although sightings are high, the number and risk of aggressive encounters are are still very low. A Stanford study, published in Frontiers in Ecology and the Environment in 2017, finds that despite increasing records of shark attacks, mostly by white sharks in California, the individual attack risk has dropped by more than 91 percent during the past six decades. The study indicates that the highest risk group, Surfers, which have a 1-in-17 million chance of being bitten by a white shark in California. According to the study, Scuba divers have a 1-in-136 million chance of being bitten.

White sharks, also called great white sharks (Carcharodon carcharias), are intriguing to many, repulsive to some and a fact of life if you are a water off the west coast of North America. Protected since 1994, our population, overfished commercially and killed in a backlash to the movie Jaws, is on the recovery.  Southern California serves as the birthing ground and nursing area for the young white sharks which consume fish including stingrays.  Subadult sharks in the eight to ten foot range transfer their diet to seals and sea lions which have more calories. Eventually these sharks head north of Point Conception where the water is colder, and the food more plentiful.

Mature adults undergo a large offshore migration, leaving the favored feeding grounds where seals and sea lions breed like the Farallon Islands, to an area near Hawaii. In the late summer and early fall, these sharks come back to forage and human encounters peak out in October (Sharktober). The best way to avoid a shark encounter is to avoid locations and seasons where risk is highest, the study’s authors advise.

Over 80% of recorded shark fatalities along the west coast are north of Point Conception. Yet even in the months of peak white shark activity in the fall we call Sharktober, shark attacks are extremely rare, more rare than being struck by lightning, falling in the bathtub or even selfies.

Surfers have the highest risk according to statistics, yet we can reduce that risk (besides trading in your board for golf clubs). For example, the riskiest time and place for California surfers is October and November in Mendocino County. That risk can be reduced 25-fold if you surf in March, and more than 1,600-fold if you surf in March between San Diego and Los Angeles.

Of course odds give little comfort to victims who become statistics, even if if you are the approximately 90% who survive a white shark attack off our coastline according to statistic from the California Department of Fish and Wildlife.

If you frequent the ocean in the Red Triangle, or dive Ano Nuevo or SE Farallon Island you have have a relative risk far greater than across the population, but that is an individual choice. To reduce our personal risk filming white sharks but still recording shark observations, Shark Stewards uses a Trident ROV at the Farallon Islands and other coastal marine protected areas as part of a National Geographic project called Open Explorer.

Sharks play a vital role in marine ecosystems, and benefit prey populations and even humans by increasing ecosystem health. There is hope that through increased awareness, better data and warning systems we will minimize shark encounters. Individuals can also take responsibility to reduce a shark encounter. Below are  suggestions we can take so both humans and sharks can swim unharmed.

  1. Avoid areas with high activity of seals in the water or where they are known to haul out.
  2. Don’t enter the water in areas of known shark activity. Known hot spots in southern California include San Onofre, Seal Beach and Sunset beaches and Pt Conception. Northern CA hotspots include Humboldt (Bunkers), the Farallon Islands, Dillon Beach, Ano Nuevo.
  3. Pay attention to Nature’s signs. Circling birds, splashing water, a dead whale, feeding seals and dolphins may also indicate a shark is near.
  4. Use the buddy system. Most shark attack survivors lived because they had immediate aid.
  5. Don’t look like shark food. A dark silhouette may resemble shark prey. Long boarders have lowest risk with swimmers and divers the highest. Patterned wetsuits and surfboards are available and touted by some but not well tested by science or time for this species.
  6. Low light may add to a mistaken predation. White sharks have an incredible sensory toolkit but are also visual predators. These sharks may mistake swimmers or surfers as a seal or sea lion during hours of low light.
  7. River mouths or areas of low water visibility can increase risk. White sharks also frequent areas with deep channels and drop offs or canyons.
  8. Don’t bleed in the water. If you have a cut get out. (The evidence of sharks attracted to menstrual blood or urine attracting sharks is inconclusive.)
  9. If you see a shark, alert others, stay calm and paddle away avoiding jerky, splashing motions and exit the water.  Warn others.
  10. Observe the signs. Beaches are posted if a large shark is sighted. Some like Stinson Beach have permanent signage. Tweets using the #SharkWatch tag, drone footage and alerts on social media often outstrip the news and can alert ocean goers where high shark activity may be occurring. Sharks patrol areas and are not locals so in time the shark will leave an area.

Final Resort? Shark survivors have described striking the nose, eyes or gills as a successful (and last ditch) approach towards inducing the shark to release them. Return attacks with white sharks are extremely rare and the odds of survival are high with immediate stabilization and care.

See a shark? Send out a tweet to SharkStewards #SharkWatch and we will record the observation and share. Learn more about sharks at Shark Stewards.org

 Join Shark Stewards for one of our Sharktober education events, Sharktoberfest celebrations and Farallon Island expeditions.