JEFFERSON COUNTY, Colo. – In just the last month, rattlesnakes have bit at least one person and two pets on Jeffco Open Space trails, according to rangers.

Plus, local veterinarians tell FOX31 they’ve treated about a dozen dogs and a cat after they’ve been bitten recently.

“That’s not uncommon, because dogs do explore off the trail corridor, and they can get in trouble with their nose,” said Jeffco ranger Mary Ann Bonnell.

That’s why she stresses people should stay on trails and keep their dogs on leashes.

In an average year, Jeffco rangers get about two to four reports of snakes biting people and about half a dozen reports of dogs getting bit.

“Rattlesnake bites usually result in tissue damage,” Bonnell said. “Usually, it’s a lot of pain and swelling.”

Centura Health, which has a number of hospitals near the foothills, has treated a few people for snake bites in 2021, but fewer than doctors might expect.

Wildlife officials say rattlesnakes are creatures of habit and are often in the same areas year after year.

“If you have chilly mornings and sunny days, rattlesnakes will be out basking to warm up, and sometimes that takes place right on the trail,” CPW spokesperson Jason Clay said. “Extra caution is also needed around dusk, when the snakes become active.”

CPW says rattlesnakes will strike if provoked. To prevent that, don’t sit or place your hands near rock crevices, dense vegetation or downed timbers.