DENVER (KDVR) — A viral livestream of thousands of rattlesnakes in a secret location in Colorado captured some of the reptiles starting to appear from their “mega den” again.

Rattlesnakes have started to come out of hibernation from a den in an undisclosed location in Colorado, which hit the internet by storm in 2024 when thousands of rattlesnakes were filmed in the surrounding area.

California Polytechnic State University researchers set up a webcam in May 2024 at a remote site on private land in northern Colorado to observe snake behavior without interfering. That 24-hour, seven days a week footage then took off when people started seeing footage of up to 2,000 rattlesnakes.

Emily Taylor, a biology professor leading the Project RattleCam research, said in 2024 that the “mega den” was one of the biggest ones they know of. Here’s what the den looked like in the summer of 2024:

Last year, 2.5 million people watched the livestream, which featured the rattlesnakes’ movements, including the live births of some pups. The rattlesnakes took refuge in the den for winter, but on Thursday, a video captured a couple of rattlesnakes emerging from their den.

Now, people can watch the reptiles for a second season.

There are only a few rattlesnakes right now, but by the end of May, hundreds of snakes will appear from outside their den.

The Associated Press contributed to this report.