Excerpt from FOX News:
The victim — one of a group of triathlete swimmers training in the ocean ....
The victim has been identified as Dave Martin, 66, a retired veterinarian....
“He had very severe injuries to both legs,” Abelman told FOX. He said the wound was a single bite across both legs.
A marine biologist told a beachside news conference Friday that the animal was “almost certainly a great white shark.”
“I was told that the victim was pushed up out of the water in a violent attack,” said Richard Rosenblatt of the Scripps Institution of Oceanography. “That’s typical great white behavior.”
Rosenblatt said the bite was likely “clean and massive” and believes the animal was a female.....
Yep judging by the damage evident in the pic this shark had a very wide mouth. Females get much larger than males. The shredding indicates violent shaking. The surge out of the water is classic seal predation behavior: hard hit at full speed.
This shark was after dinner. Other reports suggest he was swimming behind the group. That's also common: Whites pick off stragglers. Never swim alone. This shark probably stalked them for quite a while before deciding which to eat.