A wildlife spectacle that comes to Colorado once a year is in full swing.

Sandhill cranes have returned to the wetlands and barley fields in the state’s southern San Luis Valley as part of their annual migration.

Tens of thousands are known to flock from northern New Mexico, arriving to nutritious grounds such as Monte Vista National Wildlife Refuge to delight thousands of admirers. People watch the red-headed cranes flap big wings and hop and twirl on long legs during their mating dances. The custom is as ancient as their distinct calls. They take majestic flight against the backdrop of the Sangre de Cristo peaks — a photo every birder seeks.

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The Monte Vista Crane Festival — which calls itself Colorado’s oldest birding festival — will celebrate the iconic visitors March 11-13. A craft and nature fair is set for the weekend at Monte Vista’s Ski-Hi Complex, while the typical workshops and expert seminars are being recorded for later listening online.

Tours are sold out. But one can just as easily drive around Monte Vista National Wildlife Refuge on the lookout.

The cranes typically “loaf” throughout the afternoon on the preserve’s grain fields, which are mowed in the spring to provide food while it’s more limited on private lands. The birds might take to the sky at any moment, but they famously fly in and out of roosts at sunrise and sunset.

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A new study estimates their human visitors in southern Colorado to be more than 7,500 every spring, the vast majority of which come from out of the valley. Conducted by a team including Colorado Open Lands, U.S. Fish and Wildlife Service and Friends of the San Luis Valley National Wildlife Refuges, the study determined traveling crane watchers annually pump about $3.3 million into the local economy, based on surveys.

A summary of the survey also addressed the strained habitat around Monte Vista, explaining nearly 90% of the bird feed comes from leftover grain after the harvest. “As sustained droughts become the new normal,” authors write, “these private agricultural operations are struggling to maintain the habitat that has supported the cranes up until now.”

The cranes usually stick around the San Luis Valley until early April, when they leave to nest and raise chicks in Nebraska and the greater Yellowstone area.

For more information, go to mvcranefest.org.

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