It was enough to prompt the East Bay Regional Parks District to issue a warning to hikers -- and it has snake removal specialist David Allen bracing for the phone to ring, at his business that's called simply, "Got snakes?"
"Never would we ever handle a snake with our bare hands," Allen explained as he showed us the tools of his trade.
VIDEO: What to do if a rattlesnake bites you
There are two: a long hook fashioned out of a golf club, and a long-handled pair of tongs. The hook, he explained, is for the snakes that cooperate. The tongs are for the ones that don't. Either way, the snake winds up in a red bucket marked "Danger: Venomous Reptiles," which he'll use to carry it out to the woods and release it -- ideally, a mile or two from where it was found.
"The snakes are just as afraid of us as we are of them," Allen said. "To them, we are just a large animal that could potentially kill and eat them."
The fact is rattlesnakes generally don't want to eat humans for dinner. They just want to be left alone -- which means the worst thing a person can do is startle them.
"We walked around him real gently and didn't bother him," recalled Roxanne Borgfeldt as she returned from a hike in Edgewood Park.
Also finishing her hike was Barbara Newman, a retired emergency physician who's seen firsthand what a snake can do.
"I'm wary of them -- but i actually love watching them slither away," she said.
And slither away is generally what rattlesnakes will do. But if they're threatened, they'll bite.
"Usually, it's involving someone trying to capture the snake, handle the snake or kill the snake," Allen said.
Unlike many snakes, rattlesnakes don't hatch from eggs. They're born live, with all the instincts they need to hunt and defend themselves. One of the recent bites came from a baby rattlesnake in the North Bay. The victim's arm swelled up like a balloon.
"It's quite dramatic considering this is a pencil-sized snake, the degree of toxicity," said Matthew Lewin, an emergency physician who studies snake venom.
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Lewin is working on a better treatment for snake bites: one you can take orally in the field, as soon as you're bitten. He held up a tiny vial of liquid.
"A dose even this small could potentially get you to the hospital alive," he said.
That's a big deal in developing countries, where snake bites kill over a hundred thousand people a year. In the U.S., snake bites are rarely fatal, as long as the victim gets to a hospital quickly.
"The snake's venom is designed to immobilize its prey and begin digesting it," Lewin explained.
And he would know. Lewin once injected himself with a paralyzing toxin in order to test an early version of his antidote.
"But the true test will be if we can save people," he said.
The new drug could work for 35 different snake venoms, but in the Bay Area, there's only one kind of venomous snake: the Pacific Coast Rattlesnake. They eat lizards, field mice and even squirrels, but they have no interest in humans. That means they'll leave you alone as long as you stay far away.
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