Submarine: Any Truth to the Legend? Page 2   Yet another great
white, found near Kangaroo Island in South Australia,
purportedly was around 22 feet long, but only its head and
pectoral fin were saved. McCosker said he has seen white sharks
"that are at least 18 feet long off Dangerous Reef, South
Africa."  He doubts that a great white could grow much larger
than those sizes, or weigh more than 3 to 4 tons.  "The problem
becomes one of maneuverability," he explained. "A shark that
large has great difficulty capturing live prey and would have to
survive by eating large mammal carcasses."  Shark-Eat-Shark: Are
Great White Sharks Cannibals  The largest sharks, such as
basking sharks and whale sharks, tend to be more gentle and
passive filter feeders. Whale sharks can grow up to around 41.5
feet long.  "When sharks become as large as that, they can only
survive by filter feeding, like the great whales, which are the
largest mammals on earth," McCosker said.  Swimming + Fishing =
Trouble in Great White Shark Land