The tiger shark lurking in the deep waters off the Hawaiian island of Kauai didn’t give any warning; it didn’t show a telltale fin. Instead it swam up vertically from beneath surfer Mike Coots, who sat unsuspecting on his board.
“It just pulled a blindsided attack,” Coots told The Huffington Post, “Like a submarine" -- a submarine with very sharp, serrated teeth, a powerful jaw and a reputation for attacking humans.
The next thing Coots knew, the powerful fish had his leg in its mouth.
“I got this really creepy feeling,” Coots told HuffPost about the 1997 attack. “It was an incredibly creepy, spooked out, get-away-from-me feeling.”
Growing up in Hawaii, Coots had spent his entire childhood in the water. So at 17, his most basic fight or flight instincts kicked in.
SCROLL FOR VIDEO
As the shark moved its head back and forth, shaking Coots’ leg like a rag doll, the teenager attempted to stick his right hand in its mouth.
When the shark’s jaws failed to loosen, Coots punched its head with his left hand. Hitting a shark on the snout has been proven an effective strategy in shark attacks, Discovery notes. Once again Coots hit the shark, and on the second blow, the fish finally released his limb and sank back down, disappearing into the depths of the water.
Coots looked down at his finger, the one he had jammed in the shark’s mouth. As his buddy looked on in shock, Coots examined the digit.
“It was split open like a potato. I could see the bone and tissue and everything," he said.
As they began to paddle back to shore, Coots felt his right leg start to spasm, as if the shark had grabbed hold again. He looked back, and realized for the first time that his foot had been completely severed.
“A surgeon couldn’t have done a better job,” he recalled.
Slipping in and out of consciousness, Coots was rushed to the hospital, where surgeons worked to save his life. His leg, however, was gone forever.
But when he woke up in the hospital, surrounded by his family and friends, Coots felt only gratitude.
“Everyone had this kind of freaked out look,” Coots said. "My mother said, ‘you know you lost your leg,’ and I was like, duh. I kind of had this feeling that I wasn’t going to make it, so to wake up in the hospital with my family and friends, I felt pretty blessed I guess, and just really happy to be alive.”
Through months of painful recovery, and the fitting of a prosthetic limb, Coots had one goal: to return to his beloved ocean.
“That was really all I knew. It was my life,” he said. “I remember the first time getting back in the water, it was actually pretty close to where I got bit. I remember jumping in the ocean, and it felt glorious.”
Today, Coots splits his time between his old passion, surfing, and two new ones: photography and shark conservation.
The Pew Environment Group reached out to Coots, interesting him in the cause of shark finning, in which hunters kill sharks for their fins to be used in a prized soup specality.
“I love the ocean so much; I feel compelled to do something,” Coots said. As an ambassador for the group, Coots has traveled to the United Nations and the U.S. Capitol to advocate for shark conservation. In 2010, he was part of the effort to pass a ban on the possession and sale of shark fins— the first such ban in the U.S.
Today, Coots harbors no hard feelings toward the fish that took his leg.
“I feel really fortunate that I don’t have bad dreams, or hard feelings,” he said. “I really have just come to terms that I was at the wrong place at the wrong time. They just do what they do.”
Watch Mike Coots' story on Aug. 15 at 9 p.m. EST on "Shark Fight," part of the Discovery Channel's 25th anniversary of Shark Week programming.
Also on HuffPost:
Loading comments… 
Posted: 08/15/2012 11:27 am Updated: 08/15/2012 11:57 am