A rattlesnake coils in Austin. (Eric Gay/Associated Press)

It was supposed to be a sedate Sunday afternoon on the Edisto River: a group of friends kayaking along the South Carolina waterway that has been dubbed a “paddler’s paradise.” Then one member of the group paddled under a tree.

Suddenly, members of the group initially told authorities, a rattlesnake dropped from the tree and plopped into the kayak with the 28-year-old man, Michael Adams.

The snake bit the man on the hand twice, Colleton County Fire Chief Barry McRoy told the Columbia (S.C.) State. But this story was met with skepticism by an expert on snakes. And on Tuesday a man claiming to be the victim’s cousin offered a different account of what happened.

Kyle Colquitt told ABC News 4 that his cousin was the victim, and that he had picked up the snake from the water. Colquitt added that his cousin remained calm while another kayaker paddled to a nearby house for help. The Washington Post could not independently confirm this account.

After the man was bitten, the kayakers dialed 911 at about 5:20 p.m. An ambulance rushed the man to a nearby hospital, where the emergency room had antivenin waiting.

During the ambulance ride, McRoy said, the man “was in bad shape, and greatly deteriorated.” Parts of his body swelled up, the chief said, and he had trouble breathing.

The man spent the night in the Colleton Medical Center intensive care unit, Charleston CBS affiliate WCSC reported. The next day, he was flown by helicopter to a better-equipped facility, where he remained in critical condition.

The snake was captured by the injured man’s friends, but authorities have not said what type of rattlesnake it is.

Fatal snake bites are rare in the United States, according to the University of Florida’s Department of Wildlife Ecology and Conservation, which said the “chances of dying from a venomous bite in the United States is nearly zero” because of access to high-quality medical care.

Between 7,000 and 8,000 people are bitten by snakes each year, according to the university, and about five to six Americans die of the bites each year.

When presented with the kayaker’s initial account, David A. Steen, a research ecologist with the Georgia Sea Turtle Center, told The Washington Post that the story sounded peculiar.

“It is unusual for rattlesnakes to climb trees. However, timber rattlesnakes live in South Carolina and they occasionally do climb, especially when they are young,” Steen said in an email. “However, I have never heard of a rattlesnake in a tree over the water. And I have never heard of a rattlesnake in a tree over the water falling into a boat. I guess it is possible but is certainly not something that is particularly likely to happen.”

Cottonmouths are aquatic snakes, Steen said, but the South Carolina snake most likely to plop into a boat is the brown water snake, which is harmless to humans. Those snakes “hang out in trees and fall into the water when they are startled.”

Steen said that he did not know enough about the South Carolina incident to say what happened, but that people who get bitten by rattlesnakes often do so after trying to handle the reptiles.

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