ARIZONA DAILY STAR (Tucson) 19 July 05 Separating rattler facts from fiction (Anne Minard)
The more researchers study rattlesnakes, the less they seem to know.
It's certainly true when it comes to understanding the way their venom works. It was once a given for biologists that rattlesnakes only possessed hemotoxins, poisons that attack the blood and circulatory system. Blackened limbs and extreme pain are the worst-case - and most famous - symptoms.
The more serious stuff, they thought, was reserved for cobras and coral snakes: neurotoxins that could creep through your nerves to disrupt the heart rate or possibly stop it, and cause symptoms ranging from eye ticks to labored breathing.
"If you open an old textbook, it was a hard and fast rule. We're figuring out it's not that way at all," said Melissa Amarello, a local rattlesnake researcher and a recent graduate of the University of Arizona. Amarello will give a public talk this evening about banded rock rattlesnakes, a shy species that lives in the mountains around Tucson. She's also working on current projects in the lab of Matt Goode, a UA herpetologist, to document the behavior and ecology of species closer to town.
The startup of the monsoon is a usual cue for rattlers' annual birthing season. But while some studies, including one of Amarello's, have revealed that baby rattlesnakes strike more than adults, there's little reason to be fearful, she said.
"Young rattlesnakes do have more toxic venom than the adults," she said. "However, they have less. Even if they give you everything they've got … I'd much rather get bitten by a baby diamondback than an adult."
And for a while, babies won't travel far from where they're born, so the risk of running into them isn't high. But Amarello warns that desert dwellers should always be vigilant.
"There are a lot of venomous things that live here," she said. "Never have your hands and feet where you can't see them."
Local health care workers report that the majority of snakebites are preventable: They happen to people who see snakes and reach for them. These days, less than 1 percent of rattlesnake victims die in this country because of quality medical care. But treatment can cost tens of thousands of dollars.
Amarello doesn't seem fazed by the risks. She frequently goes out at night looking for rattlers as part of her research, and she recently released the first- known local tiger rattlesnake litter back into the wild after studying them in the lab.
The work she and Goode are doing is helping to tease out some of the outmoded myths about the snakes. The lab has been sending tiger rattler venom to a Colorado researcher who's interested in whether snakes' prey mandates a certain venom type.
Local blacktailed rattlesnakes, for example, may benefit from a hemotoxin that helps digest its large prey items quickly - so that its meal doesn't rot in the week it takes for the snake to digest it.
Separating rattler facts from fiction