The desert-adapted, North African imports first arrived in Arizona in the 1600s carrying supplies with Jesuit priests. Valued for their strong backs and hardy work ethic, the burros soon found additional employment with prospectors. During boom times, they hauled ore but when the mines went bust, they either wandered off or were released into the wild where they thrived in the arid territory.

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Today, their descendants wander in loose-knit social groups and are easily spotted along the park’s lakeside trails. The free-roaming herds and their habitat are protected by the Bureau of Land Management. The Lake Pleasant Herd Management Area encompasses 103,00 acres around the Agua Fria River where about 480 burros graze.