Wildlife officials release one of five gray wolves on public land in northwestern Colorado on December 18, 2023.Jerry Neal/Colorado Parks and Wildlife

This story was originally published by Vox and is reproduced here as part of the Climate Desk collaboration.

On a sunny morning two years ago, a group of state officials stood in the mountains of northwestern Colorado in front of a handful of large metal crates. With a small crowd watching them, the officials began to unlatch the crate doors one by one. Out of each came a gray wolf—arguably the nation’s most controversial endangered species.

This was a massive moment for conservation.

While gray wolves once ranged throughout much of the Lower 48, a government-backed extermination campaign wiped most of them out in the 19th and 20th centuries. By the 1940s, Colorado had lost all of its resident wolves.

But, in the fall of 2020, Colorado voters did something unprecedented: They passed a ballot measure to reintroduce gray wolves to the state. This wasn’t just about having wolves on the landscape to admire, but about restoring the ecosystems that we’ve broken and the biodiversity we’ve lost. As apex predators, wolves help keep an entire ecosystem in balance, in part by limiting populations of deer and elk that can damage vegetation, spread disease, and cause car accidents.

“This was not ever going to be easy.”

In the winter of 2023, state officials released 10 gray wolves flown in from Oregon onto public land in northwestern Colorado. And in January of this year, they introduced another 15 that were brought in from Canada. Colorado Parks and Wildlife (CPW)—the state wildlife agency leading the reintroduction program—plans to release 30 to 50 wolves over three to five years to establish a permanent breeding population that can eventually survive without intervention.

“Today, history was made in Colorado,” Colorado Gov. Jared Polis 

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