Here in the middle stretch of the Rio Grande, this time of year is an avian spectacle of sight and sound. The sandhill cranes are home for the winter. Many have journeyed long distances from their breeding grounds in the northern Rockies, and they’re here to spend a few quiet months along the river’s corridor in some relative warmth.
Look up late in the day and you might see large flocks heading south to hunker down for the night in shallow marshes, where they’re protected from coyotes and other predators. Peer across farmlands in the river valley and you might see hundreds at a time pecking away at stubble in cornfields, getting sustenance from the waste left after harvest. Listen, and you’ll hear the cranes’ staccato conversations–and if you’re lucky, the synchronized duet of a pair mated for life, which for cranes can be upwards of 30 years.
Enchanting, primeval-looking birds with six-foot wingspans, the cranes are intimately connected to the river and its valley. Each evening at dusk, thousands fly in to the Bosque del Apache National Wildlife Refuge to join equally vast numbers of snow geese to squawk and chatter and dance before tucking their crimson crowns into their chests for some sleep. On January 26, the official bird count at the refuge had tallied 10,860 sandhill cranes.
Seventy years ago, however, when the refuge was created, only 17 cranes chose to winter there. What turned the refuge into such an enticing winter home for these seasonal migrants?
In the intervening decades, wildlife biologists and ecologists have worked to restore the kinds of habitats and water regimes that the cranes and other comers to the refuge need to thrive in the arid landscape of the southwest. Today, refuge staff manage water to mimic what the wild Rio Grande used to do: they periodically divert water into large flat areas bordered by dikes and then drain it off, creating seasonal wetlands like those the undammed river produced naturally when its floodwaters spilled onto its floodplain.
These actions are crucial. According to the International Crane Foundation, the loss and degradation of riverine and wetland ecosystems are the biggest threats to sandhill cranes. What’s also important, though, not just for the cranes – but for the other birds and fish and wildlife that call the river corridor home – is to begin to restore habitats throughout the river ecosystem, along with the special sanctuary of Bosque del Apache.
Here in the middle Rio Grande, scientists and conservationists have developed plans that call for mimicking the river’s natural flows through a 160-mile stretch of the river from Cochiti Lake north of Albuquerque down to Elephant Butte, the third biggest reservoir on the river. Especially critical are peak flows once every few years that send water over the river banks and onto the floodplain.
Those natural flows used to benefit not only the native plants and animals, but the valley’s farmers, too. Lawrence Sanchez, a fourth generation farmer in the area, recalls how a half century ago the Rio Grande ran brown with sediment that brought nutrients to valley farms. Now retired from the U.S Department of Agriculture, Dr. Sanchez spends about $250-350 per acre every three years to add natural minerals and other elements to maintain his soil’s health and the nutritional value of his alfalfa and vegetables – a costly replacement for what the river used to provide for free.
In a few weeks, the fields along the Middle Rio Grande will empty of sandhill cranes. By early to mid March, the birds will spread their wings and heed the call to head north for the summer.
But come November, as the valley’s aspens turn to gold, they’ll be back. We humans might just have something to learn from the cranes about living in synchrony with nature’s time-tested cycles and seasons.
Sandra Postel is director of the Global Water Policy Project and lead water expert for National Geographic’s Freshwater Initiative. She is the author of several acclaimed books, including the award-winning Last Oasis, a Pew Scholar in Conservation and the Environment, and one of the “Scientific American 50.”
[This post has been reformatted for Water Currents.]