Archives of The Cold Blooded News

The Newsletter of the Colorado Herpetological Society

Volume 29, Number 10;   October, 2002

Too Hard to Swallow?

Bruce Jayne of Cincinnati University and colleagues describe the novel process in a paper published in this week's edition of the British journal Nature.

The hard part for the Gerard water snake in tearing apart its meal is just getting a firm hold on it. The snake clamps its mouth on the crab with relative ease. But with no limbs to use to pin the crab down, it's hard for the snake to pull it into pieces. So the snake makes itself into a loop and lassos the crab, holding it tight with its body while its head pulls off bites and swallows them.

"The snake literally rips the crab's body apart," said Jayne. "They'll tug and pull on it to tear it apart."

While researchers have observed this snake in nature before, and even knew that it eats crabs, they had never before observed the feeding process. Jayne was able to confirm the feeding method by using an infrared camera to take movies of a snake chowing down on a crab in his laboratory, in the dark. "They're kind of a bashful species," Jayne said. "They wouldn't eat when I watched them, but when I used the IR camera I found out there was this stereotypical behavior."