Citizen Science

Watching for Causes of Kestrel Decline

Male kestrel (Falco sparverius). Photo © Richard Griffin/Flickr through a Creative Commons license

Here’s a citizen science project combining nest cams and one of our coolest raptors.

American kestrels are both unmistakable and fabulously colored, with deep russet backs and tails, feathers dappled with black and cream, and slate-blue wings on the male. Also look for the distinctive black-and-white stripes on their head.

They’re also the smallest falcon species in the United States.

The Bosch Kestrel Cams, supported by the American Kestrel Partnership (AKP), bring you into the home (a.k.a. nesting box) of a pair of American kestrels as they raise their family.

While enjoying the view, you can contribute to the scientific knowledge on the behavior and diet of kestrels that could be key in restoring these once common birds.

“Many populations of American Kestrels are in decline and nobody knows why.  Although kestrel declines are mysterious, there’s plenty that the average person can do to help us figure out what’s going on!” says Chris McClure, Director of the AKP.

In addition to the nest cams, you can join the AKP by monitoring a kestrel nest box or boxes in your area.

Female American kestrel. Photo © Tatiana Gettelman/Flickr through a Creative Commons license.
Female American kestrel. Photo © Tatiana Gettelman/Flickr through a Creative Commons license.

“The AKP was founded by The Peregrine Fund in 2012 as a cooperation between citizen and professional scientists to study American Kestrels across the Western Hemisphere,” says McClure. “Our partners are currently monitoring over 1600 nest boxes ranging from Alaska to Argentina.”

Why Are the Bosch Kestrel Cams Important?

Something is behind the declines in kestrel populations.

Scientists have many theories (from climate change to depredation to environmental contaminants) about possible causes, but they need more data.

“Raptors are some of the most awe-inspiring animals on Earth, but they can also serve as indicators of environmental health. In other words, raptors can be the measuring stick by which we judge our stewardship of the environment,” McClure notes. “Just as the decline of the Peregrine Falcon and Bald Eagle warned us of the dangers of DDT, the decline of the American Kestrel might be warning us of something awry.”

Observations from the Bosch Kestrel Cams and from citizen scientist’s nest boxes around North America will be analyzed for trends that could help scientists zero in on the cause(s) of kestrel decline.

American kestrel chicks. Photo © Glyptodontidae/Flickr through a Creative Commons license.
American kestrel chicks. Photo © Glyptodontidae/Flickr through a Creative Commons license.

Their research will relate measures of nesting performance (timing, number of chicks, etc.) to environmental factors surrounding the nesting box (urban setting, climate variation, etc.).

The resulting information will inform conservation of kestrels and their habitat.

The Kestrel Cam has already captured new evidence for one theory: that European starlings compete with kestrels for nesting space.

“Our KestrelCam caught the first-ever known fight between an American Kestrel and European Starling within a nest cavity. It’s great to know that our kestrels can hold their own in a tussle!” McClure says. 

What Can You Do to Get Involved?

Getting started making observations on the Kestrel Cams is easy.

Simply go to the Kestrel Cams page, and use the “Report what you see!” box to share your observations. There are clear drop-down options and you don’t even need to sign up for an account.

Pro Tips for Observations:

* You can tell the male and female kestrels apart because the male has more blue on his head and wings.

* Kestrels will eat a wide variety of prey besides rodents — if it’s small it’s fair game — butterflies, beetles, grasshoppers, small songbirds, and even bats.

If you have the resources and a location to install a kestrel nest box, then you can join the AKP by creating a Partner Profile. You can find helpful tips on their Partner Network Start Page and FAQ.

“Joining the AKP is a fun and easy way to contribute to the study and conservation of America’s smallest and most colorful falcon,” McClure remarks.

See Matt Miller’s recent post on how efforts by the Peregrine Fund brought another raptor, the peregrine falcon, back from the brink.

Lisa Feldkamp

Lisa loves all things citizen science and enjoys learning about everything that goes on four legs, two wings or fins - she even finds six and eight-legged critters fascinating at a safe distance. She has a PhD in Classical Literature and Languages from the University of Wisconsin - Madison and enjoys reading Greek and Roman literature or talking about mythology in her spare time. More from Lisa

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Justine E. Hausheer

Justine E. Hausheer is an award-winning science writer for The Nature Conservancy, covering the innovative research conducted by the Conservancy’s scientists in the Asia Pacific region. She has a degree from Princeton University and a master's in Science, Health, and Environmental Reporting from New York University. Justine's favorite stories take her into pristine forests, desolate deserts, or far-flung islands to report on field research as it's happening. When not writing, you can find her traipsing after birds, attempting to fish, and exploring the wild places around her home in Brisbane, Australia. More from Justine

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  1. We have them in our backyards over here..but I see people throw PREEN, ROUNDUP put out the blue pellets to poison chipmunks, mice squirrels…I pick up, hide and dispose of all of these from my boyfriend who insists on using this toxic waste. So when I see neighbors use it and the Hawks and such pick up the small wildlife…I would think they are ingesting the poison as well…sadly

  2. Regarding the reported decline in American kestrel populations. Two things strike me as significant. One is increase in powerlines, guided cell-phone towers, wind turbines, etc. These things must kill millions of birds, not just Kestrels. Birds migrating at night literally run a gauntlet of obstacles. Why Federal and State agencies don’t require these utility companies to mitigate for the birds they kill is beyond me!

    The other thing that is almost a no-brainer is the loss of habitat in farm country. We see Kestrels sitting on wires above roadsides because that is about the only habitat left for them to hunt in for food. Since
    the price of corn went to $7 a bushel, millions of Conservation Reserve Program acres went under the plow along with fencerows, shelterbelts and other field borders that were all foraging habitat for Kestrels. Our landscape is changing, to the detriment of wildlife and if you don’t believe it, visit a USDA office in just about any farming County in the U.S.A. Ask to look at aerial photos of a few sections taken recently and compare them to photos of the same area from 40 or 50 years ago, or even 20. This tells a lot about what’s happened to many wildlife species, and probably Kestrels.