[♪ intro ♪] Meet the Duke of Burgundy.

Not the person, but the butterfly: Hamearis lucina. This beautiful butterfly lives in England.

But unfortunately, its numbers dwindled after we took over much of its grassland home for farming and managed the land poorly. Thankfully, the Duke of Burgundy is regaining population, in part because we built it a bridge!. Now a bridge for a flying animal might sound unnecessary.

Can’t it just fly wherever it wants? Well, no. Because not all butterflies fly the way you might think.

A lot of them can’t fly very far, or very high. In their native, undisturbed habitat they don’t have to. They could just go for short flights from one part of their habitat to another and eventually make it pretty far from where they started.

But when human activity split up their range so that the next habitable area became farther away, they got stuck where they were. And a 2021 analysis found that those that stick to smaller areas and don’t fly as far are usually worse off. The Duke of Burgundy butterfly doesn’t usually fly to habitats more than 100 meters from their home.

Likewise, California’s Quino Checkerspot butterfly stays pretty low and tends not to fly over six feet above the ground. So they can easily become separated from a nearby habitat by daily traffic. These can be big problems for butterflies that end up being cut off from other potential homes.

Because soon, they can become restricted to a smaller group of mates and less food. which can result in hunger and inbreeding.~ By giving these butterflies a safe and habitable path from one livable space to the next, we can increase their food and mate options. And that’s what a habitat bridge is. These habitat bridges can take the form of literal bridges over a highway or strips of land that go undeveloped so that butterflies can make their way to the next larger livable area.

The Duke’s bridge looks like a cleared path, or ride, through denser plant life. And these kinds of land management efforts have brought butterflies like the Hamearis lucina back from near extinction. That particular butterfly’s population has grown by 90% since starting efforts in 2003.

Because we only begin to help the Duke of Burgundy after recognizing how they live, die, and fly. [♪ outro ♪ ]