Taxonomy

Rarity

The white shark is the most protected fish in this Ichthyopedia and the one people ask about most.

California prohibits taking one outright. Under state regulation a white shark may not be taken except under a scientific or educational permit, and if one is caught it must be released immediately and may not be removed from the water. The state Fish and Game Code goes further and bans the bait as well as the catch: it is unlawful to use any shark bait, lure or chum to attract a white shark, to put chum in the water within 1 nautical mile of any shoreline, pier or jetty when a white shark is visible or known to be present, or to put chum in the water to view any shark when a white shark is visible or known to be present. Federally it is a prohibited species in West Coast highly migratory species fisheries, with no retention allowed; a shark caught incidentally may only be sold or donated to a recognized scientific or educational organization.

The International Union for Conservation of Nature assessed the species in 2018 and lists it as Vulnerable, meaning a high risk of extinction in the wild, and it sits on Appendix II of the international wildlife trade treaty.

The protection is not the reason a southern California diver rarely sees one. The reason is that the population here is concentrated in a handful of specific places, which is a fact somebody actually went and measured.

Seasonality

Location

White sharks are among the most widely distributed fish on the planet, living in most oceans and tolerating water anywhere from 41 to 77 degrees Fahrenheit. They hold over continental and island shelves and out past them, usually in the top 820 feet. They are usually alone or in pairs, they do not school, and they will gather in feeding groups of 10 or more when there is something worth gathering for. FishBase describes them as often close inshore to the surf line, and as penetrating shallow bays.

For southern California, that last sentence is the whole entry, and there is good local research on it. Juvenile white sharks of the northeastern Pacific population, roughly 5 to 10 feet long, gather off southern California beaches in mixed-size groups for weeks to months at a time, often within 1,600 feet of shore. Between January 2019 and March 2021 a research team ran 1,644 aerial drone surveys across 26 southern California beaches to find out where those sharks were and how close they came to people.

What they found was concentration. The distribution along the coast was clumped rather than spread out: of 1,204 juvenile white shark sightings, 1,096 were at just 2 places, Carpinteria and Del Mar. Within those places the sharks held a median of 331 feet from shore, with individual sightings from 7 feet to 2,303 feet out, which puts them close enough to the wave break to share water with people. The group they overlapped with most was stand-up paddlers.

The diet is the broadest of any shark: bony fishes, other sharks, rays, seals, dolphins and porpoises, seabirds, carrion, squid, octopus, crabs and whales.

Deep Dive

The most useful thing this entry can do is answer the question everybody actually has, and the answer comes from the same drone study.

At the beaches where juvenile aggregations had formed, sharks and people were in the water together on 97 percent of days. And across all of southern California over the same period, the number of unprovoked shark bites was extremely low. The authors state the conclusion directly: high overlap between sharks and water users does not lead to more bites in southern California. People and juvenile white sharks share the surf at Carpinteria and Del Mar nearly every day, and nothing happens.

That does not make the animal harmless and the entry is not going to pretend otherwise. FishBase classifies the species as traumatogenic, records that some experts believe white sharks attack people having mistaken them for normal prey, notes that most attacks occur in estuaries, and says the species is sometimes considered the most dangerous shark in the world. Those are the records. So is the 97 percent. Both belong on the same page, and the honest reading is that a juvenile white shark in southern California is an animal a diver is very likely to be near and very unlikely to be bitten by.

The size figures need care because this is a species people exaggerate. The maximum recorded total length is 21 feet. FishBase notes the maximum is "leading to much speculation and some measurements are found to be doubtful," and states flatly that the widely repeated record of 10.98 meters, which is 36 feet, is incorrect. The oldest recorded individual was 36 years old. A white shark does not reach sexual maturity until about 15.6 feet, which is most of its length and many years of its life. FishBase carries no maximum weight for the species at all.

Reproduction follows the mackerel shark pattern and is as slow as the mako's. The eggs hatch inside the mother and the pups grow there, feeding first on their yolk sacs and then on unfertilized eggs the mother produces for that purpose. A litter is 7 to 14 pups, each born at 3.9 to 4.9 feet long, which is already larger than most adult fish on this coast. No gestation length appears in the sources read for this entry, which is a genuine gap in the record for the most studied shark in the world.

One last piece of local context. The sharks gathering off Carpinteria and Del Mar are juveniles, between roughly 5 and 10 feet, and researchers describe these beaches as nursery habitat that the young sharks use without adults present. They prefer the warm, shallow water close in. The animal most southern Californians picture when they hear the name is a mature shark of 15 feet or more, and that is not the animal holding off the beach.

Where to Find Them

Beaches whose habitats match this species

Matched by habitat: a beach is listed when its biome tags overlap this species' biomes.