When the sun goes down on the jungle of Belize, there’s an air of mystery in the darkness. This is when vast colonies of bats begin to stir within the Mayan ruins and this is the moment the bat girls have been waiting for: now they too get to hunt, catching bats in their nets. Gliselle Marin, a young Belizean scientist with bats tattooed on her neck, is the keenest of them. For her, this is personal: it’s about protecting Belize’s biodiversity and caring for the strange creatures she loves most.

“I’ve always been very interested in animals that are misunderstood,” she whispers. “I grew up in the jungle, with bats roosting under our porch. I thought this was normal. It was only when I talked to city people that I learned they were afraid.”

Gliselle is one of the key subjects of Empire Of Bats, a one-hour documentary for CBC’s The Nature of Things, hosted by Anthony Morgan, that tells the story of an extraordinary research project called the “Bat-a-thon”. Each spring, bat researchers from 50 institutions in two dozen countries travel to the ancient Mayan community of Lamanai in Belize for a two week joint study of the dozens of species of bats that live there. Started and run by Canadian researchers, the “bat-a-thon” is an unprecedented gathering that is discovering the secrets of bats and the many puzzles of human health – from diabetes to infectious diseases – that they may help to solve.