William Krause had been spearfishing with four other divers in the Bahamas in 2018 when he felt a "big impact" on his head.
"I didn't realize that a shark had bitten me," Krause explained.
The shark attack survivor recounted the "out of body" experience he felt being unknowingly bitten from behind on "Jesse Watters Primetime."
FOOTAGE CAPTURES GROUP OF SHARKS SWIMMING JUST BELOW SURFER AT CA BEACH
Krause had thought the initial impact was from the nearby boat they had arrived on. He thought he had been hit by the boat. It was only by seeing footage and hearing his friend's description of the attack that he realized the impact had come from a shark.
Krause explained that swimmers notice sounds the most when they are underwater. He recounted hearing the fish being shot with his spear and the boat going into gear.
"And I do remember the sounds of my head and the hair and the crunching," he said, highlighting how that was not a sound he was familiar with or a "comfortable" feeling,.
On what may have prompted the shark's attack, Krause discussed how he believes sharks are "pretty lazy hunters" and "opportunistic."
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If presented with wounded fish or the smell of blood, sharks see that as an "easy meal" that they "don't have to work very hard" to snag, he explained.
Still, Krause realizes he was lucky to survive the encounter.