A tour guide wrestled a 10ft python to its death after "ambushing" it in front of a boat-load of tourists and performing what he described as "snake jujitsu".
The astonishing battle was captured on video by holidaymakers who watched as Tommy Owen tackled the Burmese python, one of Florida's most dangerous species.
Mr Owen, 26, fought with the snake for several minutes before holding it still long enough for his partner, Warren Wortman, to cut its head off.
They were travelling with the tourists when the snake was spotted.
Mr Owen said: "They don't belong here and that was literally running through my head.
"I just launched on it essentially, ambushed it like any other predator out here and just got it - had the best grip on it and never let go the entire tussle."
He added: "I didn't even realise it was 10ft (3m), definitely thought it was over 6ft, definitely bigger than me. I didn't realise it was three times the size of my arm.
"With a snake especially that big, you get one chance to grab it by the neck where it doesn't bite you. I had him, eventually exposed the neck to Warren. I want the head away. That's the most dangerous part of the snake so I exposed the neck and he was able to eventually make that cut."
Jack Shealy, owner of Everglades Adventure Tours, said that in the generations his family has run the business he had never seen a python caught on camera.
He said: "Even rarer then encountering a snake is someone jumping on it. Tommy's always been a wild man growing up with him."
Pythons are native to South East Asia. The first one was found in the Everglades National Park in 1979 and since then the population has boomed.
Experts say that originally the Burmese pythons were introduced to the area because they were unwanted pets that were abandoned and found their way into the national park.
Researchers at Virginia Tech University, Davidson College and the US Geological Survey reported that foxes and rabbits had disappeared from the area and that the numbers of raccoons and bobcats had dropped by as much as 99%. The snakes are blamed.
So Mr Owen believes he was performing a vital service by killing one.
He said: "Unfortunately, that's the problem. I had to make sure that I got this one because it's one less out there - one less eating native species."
The snakes have become such a problem that this year authorities introduced a python-hunting competition with a \$1,500 (£974) prize for the person bagging the most snakes and a \$1,000 (£650) prize for the person capturing the largest one.
The biggest python found in the national park was 17ft 6ins.