Colorado, USA – Thousands of bats poured from the rocky entrance of the Orient Mine in a massive swirling cloud as they spread across the evening sky above a mountain valley.

The footage showed the bats streaming out over distant peaks and a small green field below as dusk settled over the landscape.

Colorado Parks and Wildlife said summer is the best time to see bats across the state as warmer temperatures and abundant insects bring increased activity.

A second video showed bats darting and skimming low across the calm surface of Waneka Lake at twilight, while others flew higher against a backdrop of silhouetted trees and distant lights.

On-screen text in the video read, “Watch them fly high Or skim the water!” alongside a location tag for Waneka Lake.

Colorado Parks and Wildlife said the footage from the historic Orient Mine showed a large colony of Mexican free-tailed bats, also known as Brazilian free-tailed bats, leaving to forage for insects during warm summer evenings when activity is at its peak.

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