Ten years ago, a butterfly called the Duke of Burgundy was listed as Britain’s rarest, with the species hurtling towards extinction. Thanks to wildlife-friendly farms, however, the population of the small butterfly has now bounced back, with the number surging by 25 percent over the last decade.

Last spring, one of the biggest colonies of Duke butterflies was discovered by Martin Warren, a renowned butterfly ecologist. Though the discovery was made by chance, the thriving population on a green hill in the county of Dorset is no accident.

The area is farmed by John Hiscock, an organic dairy farmer who supplies major supermarket chain Waitrose, which requires farmers to devote at least 10 percent of their land to wildlife.

Supported by government subsidies for wildlife-friendly farming, Hiscock fenced the hill and lightly grazed it with cattle, creating the perfect conditions for wildflowers favored by Duke caterpillars and butterflies to grow.

As the Guardian reports, like many other farmers, Hiscock is “thrilled” that he is reviving wildlife. “We have farmed organically for more than 20 years, with no pesticides, sprays, or chemical fertilizers, allowing the wildlife habitat to improve and these rare butterflies to thrive along with many other species,” he says.