This is the spectacular moment thousands of bats flew together across the sunset sky as they headed out for a night of hunting.
The nocturnal creatures made the incredible shape as they left their caves and began a night's work in Phitsanulok province, northern Thailand, on Tuesday (Dec 30).
Onlooker Beau said the natural phenomenon lasted for more than an hour.
"The bats just kept coming and coming," she said. "Even an hour later they were still flying from the caves. It was dark and they were still going."
Thailand is home to several species of bats. They live in the country's cavernous mountain regions.
