AT DUSK, the birds returned in waves to the Wetland Roost at Bosque del Apache National Wildlife Refuge. Hundreds of snow geese floated in the water as the rest of the overwintering flock looked for a clear spot to land. In sets of twos, threes, and fours, the geese thrust their feet forward, pulled their wings back, and splashed down for the night.

The sandhill cranes seemed to come from miles away—their bodies pointed straight from tail feather to beak. Set against the mountains, flying low over the trees, these ancient birds have perfected this approach over eons. Like an orchestrated New York fashion show, the return from their daytime feeding grounds synched up with the setting sun so their lanky gray bodies were silhouetted against the purple and pink sky. They broke form only to cut their speed, unfurl their spindly legs, and drop into their watery resting place.

A raucous symphony of honking, squawking, and clucking welcomed each group back from a day in the fields like kids in the schoolyard at recess.

While the number of sandhill cranes at Bosque del Apache has declined, it doesn't mean they are in danger. Photograph by Christina Selby.

My wife, Kathleen, and I had arrived at the refuge near San Antonio earlier in the afternoon and spent the mid-November day photographing the snow geese as they floated leisurely in a pond. We hiked the network of trails (including one with a rather aggressive javelina), and basked in the beauty of the place while driving the 12-mile tour loop.

But mostly, we were there to see the cranes—one of the most beloved animals in our state, even though they only spend part of the year here. So I was excited when environmental writer and photographer Christina Selby proposed a story about the changes happening at Bosque del Apache and other wildlife refuges in the Río Grande Valley—all designed to ensure the health and endurance of the birds during times of drought.

In this month’s “Flight of the Cranes," Selby looks at the complicated reasons why the number of sandhill cranes has been declining over recent years at Bosque del Apache. After speaking with wildlife managers and biologists, she explains how it’s actually part of a larger plan to redistribute these beautiful creatures throughout the region.

And while that decline may be disappointing to some visitors, the reasons behind it are important—so future generations can continue to enjoy the wonders of birds that have visited New Mexico for millions of years.

Read more: Bosque del Apache’s migration of sandhill cranes, snow geese, and ducks makes a spectacular show.