People wanting to hike at North Table Mountain are now greeted by a big, electronic sign telling them a popular trail is closed. Jefferson County Open Space closed Cottonwood Canyon Trail on Friday after finding a group of rattlesnakes getting ready to hibernate nearby.

However, their work to protect hikers doesn't end with closing trails. Researchers are using technology to track exactly where the rattlesnakes are. Previously, they surgically implanted tracking devices into 20 different snakes. To locate the snakes, the researchers are using antennas.

"They'll dial an individual snake's frequency into the antenna and hold the antenna up," said Mary Ann Bonnell, JeffCo Open Space's Visitor Service Manager. "They'll begin to hear a signal and that is the direction that the snake is in."

By learning exactly where the snakes are moving, researchers will also be able to find out where the snakes are hibernating, too. While many people may be surprised to hear about a trail closure due to a few snakes, it's important to note that rattlesnakes prepare for hibernation in massive numbers.

"If you have a really nice hibernaculum, a lot of snakes are going to use it and they may not even all be of the same species," Bonnell said.

According to Colorado Parks and Wildlife, rattlesnakes usually hibernate from October 20 to March 20.

To avoid a potentially dangerous confrontation with a rattlesnake, JeffCo Open Space strongly recommends you stay on trail, keep all dogs on leashes and keep at least one earbud out if you're listening to music so you can hear if a rattlesnake is nearby.

If you do happen to encounter a rattlesnake, Bonnell said to follow what they call the "30 and 30" rule. If you spot a rattler, back up 30 steps and wait at least 30 seconds before continuing on.