American Kestrel

a community science mystery
Researchers have yet to find the definitive threat—or threats—that are making this “common” species uncommon. As the global specialist for birds of prey, we have united researchers to develop the big picture before it’s too late…


a male kestrel delivers a mouse to a female kestrel

Jim Shane

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American Kestrels are North America’s most plentiful falcon, guarding cityscape ledges or hovering over rural roadsides to hunt rodents and insects. This small falcon is familiar even to casual observers, but a look at population levels reveals a perplexing mystery: continent-wide, kestrels have declined by nearly half since the 1960s.

The American Kestrel ranges from the Yukon to Tierra del Fuego, so compiling a “snapshot” of kestrel life requires a veritable army of observers. Fortunately, kestrels are cavity-nesters and readily inhabit nest boxes during the breeding season, making observation relatively simple so that virtually anyone can contribute data to our continent-wide study. “Community scientists” are the eyes, ears, and hearts of the American Kestrel Partnership, contributing countless hours and enthusiasm and creating an international community throughout the Americas to unite people based on love for their backyard falcon.

Threats to American Kestrels

Knowledge Gap
A citizen scientist checks a nest box for activity during breeding season


our impact
As of July 2023, professional and community scientists have contributed more than 55,000 observations from over 5,000 kestrel boxes and other nest cavities, getting us closer to understanding the mystery of the slow, steady, and long-term decline of the American Kestrel.

Our partners have contributed more than 700 blood or feather samples from across the continent for genetic analysis, helping scientists better understand kestrel populations across North America.

female kestrel feeds nestling inside a nest box
our impact

From 2012 to 2017, we invited community scientist partners to report activity streamed live online from a kestrel nest box. They contributed more than 27,000 observations! We found that 88% were accurate, and published the findings. We encourage the greater conservation community to consider wildlife webcams for conducting community science.

Join our American Kestrel Partnership

Although many local nest box programs exist, the American Kestrel Partnership is the only coordinator of an international network of professional and community scientists, managing a single database to look for far-reaching trends that could explain population declines.

Now with more than ten years of data, we have narrowed our inquiry to go beyond simple “head counts” and delve into questions about the kestrel’s life cycle. Are adults returning after winter to breed? Are they dying at high rates during breeding, migration, or over-wintering? Are they breeding less often, or failing when they do breed? And, critically, how are they affected by land use, contaminants, climate, predators, and other species? To find answers, our colleagues at Boise State University and UCLA are conducting genetic analyses using feather samples gathered by our partners throughout North and South America.

We’ve also discovered that in nest box studies, just as in real estate, location is key.

Nest boxes are not the “golden ticket” to halting population declines, and could even harm wildlife if placed incorrectly. These findings reinforce our focus on responsible nest box placement and standardized, consistent monitoring to ensure that American Kestrel boxes are placed in safe locations.

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