A great white shark was spotted off Stinson Beach in Marin over the weekend — and now swimming and surfing in deep water are prohibited through Thursday. Bay Area coastal waters are part of the so-called “Red Triangle” because of the large number of great whites patrolling the waters for prey. How big of a threat do these sharks pose to humans?

Douglas Long, chief curator of natural sciences at the Oakland Museum of California and research associate at the California Academy of Sciences

  • James D Ivey

    Did I hear the lead-in to the show correctly, that Northern California leads the nation in shark attacks?  I understand that bull shark (common at the beaches in Florida) actually like eating people.  Is it that we lead the nation in _white shark_ attacks?  or _all_ shark attacks?

    • Richard

      Current research has indicated that not only do great whites have an aversion to the taste of humans, but that this characteristic is common to virtually all shark species.  That doesn’t provide a conclusive answer, however.  Incidents such as the sinking of large ships in World War II, wuch as the Indianapolis, with large loss of life due to shark attack, are often attributed to situations that are seen as opportunistic for the predator – an absence or scarcity of the normal food source coupled with a large number of people who exhibit prey behavior – high heart rates (fear), and long exposure times. 

      Because marine scientists prevalently share the idea of an attack as a “mistake” on the part of the shark, it’s not greatly different than the analogy of the deer that shoots a cow in a wooded environment after seeing the “flash” of a tawny coat through the leaves in the forest.

  • Fay

    Any idea if surfers are attacked because they wear BLACK wetsuits that mimic the colors or animals like sea lions? In contrast, if the wetsuits were bright orange, would surfers be less likely to be bitten; do sharks see color or do they strike by movement and sonar alone?

    • Anonymous Surfer

      Fay – bright wet suits have names like “yum yum yellow”… for obvious reasons, surfers and divers avoid that colour scheme.

  • Deanne

    Sharks also have cultural importance. Hawaiian people consider them the embodiment of some of their ancestors, called aumakua. Some years ago there was a particularly high-profile tiger shark attack that was followed by a massive shark-hunt, presumably to find the offending animal and eliminate it from the waters near the islands. This was folly, of course, for obvious reasons and also enraged Hawaiians as a gross insensitivity toward nature and their culture.

  • Richard

    As a diver with an interest in animal behavior, and many years of diving off the California Coast, I have had the opportunity for encounters with great white sharks.

    Recent science supports the idea that great whites attack humans only by mistake.  We do not have enough body fat, and the right types of fat to be an attractive food source.  it takes too much energy to digest human flesh.  In fact, for the amount of time it takes a shark to digest a human, coupled with a shark’s energy consumption needs we are a net energy drain.

    Divers also have the opportunity “face time” with large aquatic fish and mamals.  Great wites who are familiar with divers, such as the 14 foot female that frequents a well known “advanced” dive site on the Monterey Peninsula, is preceived by the divers who know her as a docile creature.

    Large predators, whether in the ocean or on land tend to be curious creatures.  Great whites in the vicinity of the Channel Islands who see fewer divers tend to exhibit more typical predator behavior when approaching divers.  (It’s an unsettling experience.)  The only way we have “managed” the behavior of great whites in that locale, is by assuming predator behavior.  We turn to face the great white shark, shine a dive light in it’s eyes, and swim toward it.  They always flee.    

  • Cshaw789

    I wish I could find answers to these three questions:
    1) When I hear the statistics about the unlikelihood of experiencing a shark attack, I wonder if the ratio is based on those that go TO the beach or those that go IN THE WATER.  I go in the water.

    2) Along with that idea, is it safer to be near a crowd in the water (splashing etc) or alone and calmer.

    3) Does the color or design of my swimsuit possibly attract sharks?

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