Great white sharks may not be the world's biggest sharks, since that title goes to the whale shark, but they are the planet's largest known predatory fish. Whale sharks and great whites couldn't be more different in temperament. While not vegetarians, whale sharks consume a lot of plant material and spend their days peacefully filter feeding. Great whites, on the other hand, stealthily hunt for survival by ambushing their prey before taking a bite and waiting for the hapless victim to bleed to death. Their hunting prowess goes unquestioned, but the great white's actual size has vexed ichthyologists for centuries.
A Big Fish Tale
Fishermen notoriously exaggerate the size of their catches, and so it holds that fishy stories have accompanied noteworthy, infamous shark landings over the years. A widely distributed photo taken in 1945, for example, shows a great white shark caught in Cuban waters. Known as the "Cojimar Specimen," the shark at the time was said to measure 21 feet long and weigh 7,100 pounds. An entire village seemed to come out for the photo, since several adults are seen in the background, while kids sit on the long-dead shark, legs dangling over the side.
Later analysis of the photo by experts, such as R. Aidan Martin of the ReefQuest Center for Shark Research, suggests the shark fell short of its stated size. Martin instead concluded it measured around 16 feet in length, with a weight that's hard to determine just based on a single photo. Newspapers and home photo albums are full of similar, unconfirmed great white tales.
The World's Largest Great Whites
Turning the page away from fishing lore to the scientific literature still reveals discrepancy and confusion about great white size. Over the past two decades, most researchers accepted that the largest great white was a 23-foot individual caught in 1987 off the coast of Maltaby Alfredo Cutajar. More recent studies on information concerning the specimen suggest its length had been exaggerated. One possible problem is that sharks, like all fish, are composed mostly of water. As a result, they can dry out and shrink over time. This happened in 2008 to a colossal squid housed at the Te Papa museum in New Zealand. There is no question the squid shrunk after months of storage upon capture, but now the measurements only reflect its size upon validated scientific examination.
According to the Canadian Shark Research Center, the world's largest accurately measured great white was 20 feet in length. This was a female caught in 1988 at Canada's Prince Edward Island. Local fisherman David McKendrick landed the toothy catch. In terms of largest measured live sharks in captivity, these tend to reach 10 feet or less, because these fish are often juveniles. The Monterey Bay Aquarium in California, for example, has housed several such great whites over the years. Usually the sharks go on exhibit for several weeks before being released back into the ocean.
Experts mainly agree that 20 feet is the more common maximum size for a great white, with these larger individuals weighing around 4,200 pounds. Females tend to be larger than males, so they can fall into the 20-footer group. The majority of great whites, however, measure between 13 and 16 feet with an average weight of 1,500 to 2,450 pounds.
Size Isn't Everything
As for the human world, size can matter among competitors. Few ocean dwellers dare to tangle with great whites. Enormous orcas have been known to fight with them, but rarely. Gangs of dolphins have also taken on individual sharks by head-ramming them in coordinated attacks, which have resulted in past great white deaths. The shark's size, keen sensory perception, and ability to move swiftly and decisively all help to make great whites top-of-the-food chain apex predators, but one feature, in particular, cements their status: teeth.
Great white sharks possess row upon row of saw-like, razor-sharp teeth. Recent studies have determined that sheer biting force is not as important in disabling prey as the devastation inflicted by the shark's initial chomp, followed by rapid side-to-side head shakes. So even though great whites might not live up to their size reputation in fish lore, or even surpass whale and basking sharks in size, their bite proves mightier than their length and bulk.