How Wild Burros Are Transforming Desert Ecosystems

Wild burros, often labeled as invasive, are proving to be unexpected allies in desert ecosystems. Field biologist Erick Lundgren's research reveals how these animals are digging wells, providing crucial water sources for various wildlife species.

Field biologist Erick Lundgren of Phoenix, Arizona, was camping along a river in the Sonoran Desert, as he had for years, when he noticed something odd: dug wells. Curious to find the culprit of these wells, he secured a small grant with Arizona State University to purchase trail cameras. The footage showed that the wild burros who roam the unforgiving landscape are digging wells of more than a meter deep to reach subterranean water in the desert.

Burros are often described in the scientific community as "scourges," with most studies stating that they overgraze and outcompete native species. But Erick is finding different results.

From his preliminary data, it appears that burros are significantly increasing water access across the desert. He explains, "I have found sites that are very arid, with limited and seasonal surface water, where burro-wells maintain access to subterranean water throughout the year. Furthermore, in certain contexts, these burro-wells appear to function as vegetation nurseries; significantly more cottonwood and willow seedlings germinated in abandoned burro-wells than in adjacent riverbank zones."

And these wells are not just helping the burros to survive. The footage shows at least 13 species drinking water from these wells, including javelinas, bighorn sheep, and coyotes.

This type of behavior from burros has never been described in scientific literature, and Erick thinks that's because burros are currently viewed as invasive—but that needs to change.

"I am beginning to realize that to demonize a species because it doesn't belong may prevent us from seeing what it actually does," he said.