U.S. diver killed by shark in Australia

The White Shark, more commonly referred to as the "Great White," has been reported to be involved in more attacks on humans than any other shark. Fossil remains suggest the Great White dates back to the early Eocene eras, which lasted from about 56 to 34 million years ago. Mature males reach an average size of 10.5 feet while females can average 14 feet. Active during daytime hours, Great Whites feed on marine animals - they don't like sea birds or sea otters particularly. It's thought that they attack humans when they mistake diver and surfer silhouettes in the water during approaching from below the surface of the water. An alternative theory has also been suggested that Great Whites attack unfamiliar objects to test their potential as food. If true, that would help explain their involvement over the years in myriad hit-and-run attacks near beaches. Not very much is known about the size of the great white's total population. Described as a slow-growing animal with low fertility rates, the Great White is considered at risk of overfishing.

CANBERRA, Australia - A great white shark killed an American diver Saturday in the second fatal shark attack off Western Australia state in 12 days.

A witness on a dive boat saw "a large amount of bubbles" before the 32-year-old man surfaced with obviously fatal injuries, Western Australia Police Sgt. Gerry Cassidy said.

Two people on the boat described the shark as a 10-foot great white, Cassidy said.

The shark struck 500 yards north of the picturesque tourist haven of Rottnest Island, which is 11 miles from a popular Perth city mainland beach where a 64-year-old swimmer is believed to have been taken by a great white on Oct. 10.

The American was living in Perth on a work visa. Police would not release his identity or hometown.

Authorities cannot say whether he was killed by the same shark that is believed to have taken Bryn Martin as he made his regular morning swim from Perth's premier Cottesloe Beach toward a buoy about 380 yards offshore.

But an analysis of Martin's torn swimming trunks recovered from the seabed near the buoy pointed to a great white shark being the culprit. No other trace of Martin has been found.

"It's a cloudy old day today which is the same as we had the other day with Cottesloe, and they're the conditions that sharks love," Cassidy said.

It is the third fatal shark attack off Western Australia in less than two months and the fourth in 14 months. Fatal shark attacks average fewer than two a year nationwide.

2 Great Whites attack, kill diver in Australia

Premier Colin Barnett, the leader of the state government, said the shark will be hunted and killed if possible.

He said fisheries officers will spread bait in the area of the attack to try to catch the shark.

Great whites can grow to more than 20 feet in length and 5,000 pounds in weight. They are protected in Australia, a primary location for the species.