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Valerie Allan, left, and Becky Lippincott watch as Sandhill Cranes head to their feeding grounds at sunrise at the Monte Vista Wildlife Refuge during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

A Sandhill Crane feather rests in the ground near the Monte Vista Wildlife Refuge Saturday, March 9, 2019 in Monte Vista.

Sandhill Cranes head to their feeding grounds at sunrise at the Monte Vista Wildlife Refuge during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

Sandhill Cranes leave their roosts at sunrise at the Monte Vista Wildlife Refuge during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

Sandhill Cranes dance as they feed during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

Photographers take photos of Sandhill Cranes during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

A photographer takes photos of Sandhill Cranes overhead during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

Janel Possiel, left, and Eric Dinkel watch a flock of Sandhill Cranes during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

Sandhill Cranes take off during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista, Colorado. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

A flock of Sandhill Cranes fly past the Sangre de Cristo mountains during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

Birders watch as Sandhill Cranes take off at sunrise during the 36th Annual Monte Vista Crane Festival Sunday, March 10, 2019 in Monte Vista.

Sandhill Cranes take off at sunrise during the 36th Annual Monte Vista Crane Festival Sunday, March 10, 2019 in Monte Vista.

Sandhill Cranes take off at sunrise during the 36th Annual Monte Vista Crane Festival Sunday, March 10, 2019 in Monte Vista.

A flock of Sandhill Cranes head tot heir roosting grounds at sunset during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista, Colorado. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.

Sandhill Cranes take off at sunrise during the 36th Annual Monte Vista Crane Festival Sunday, March 10, 2019 in Monte Vista, Colorado.

Birders wait for Sandhill Cranes to leave their roosts at sunrise at the Monte Vista Wildlife Refuge during the 36th Annual Monte Vista Crane Festival Saturday, March 9, 2019 in Monte Vista. More than 20,000 cranes migrate through the San Luis Valley from mid-February to mid-April as they head to their nesting grounds in the Greater Yellowstone ecosystem.