Conserving Kestrels

Supporting an iconic grassland species.

A kestrel spreads its wings in flight. (photo: Susan Kline)

A kestrel lifts its wings in flight. (photo © Susan Kline)

American Kestrel

Falco sparverius 

American Kestrels are small, colorful falcons of grasslands and agricultural areas. Roughly the size of a dove, they’re the littlest falcons in North America. You’ve likely seen them perched on a telephone wire or fence, where they might be eating a small animal such as a butterfly, grasshopper, vole, mouse, or even a snake. Kestrels breed in cavities — often in trees along the forest edge — and typically lay four to five eggs per clutch. During the breeding season, you might observe males defending their territory by ascending high into the sky and repeating killy! during dives (source: All About Birds).

A Species in Decline

A kestrel in flight over Pack Monadnock. (photo © Martha Duffy)

A kestrel in flight over Pack Monadnock. (photo © Martha Duffy)

Once common when pastures and fields dominated New England, the kestrel has declined across its entire range — especially in the Northeast, where fields have been converted to both forests and houses. In New Hampshire, the kestrel is now considered a Species of Special Concern.

A major limiting factor to successful breeding in the Monadnock Region, aside from the absence of large (10+ acre) fields, is a lack of suitable nesting cavities. Although open landscapes still exist in nearly every town, well-placed natural cavities for nesting are less available. Due to agricultural changes, forest pests, and a variety of other factors including the decline of grasshoppers and other large insects (an important food source for kestrels), it is now a rarity to see a kestrel using a natural tree cavity.

By placing nest boxes in large fields, we can begin to reverse the decline and, hopefully, increase kestrel populations across the Monadnock Region. To date, we’ve installed 45 nest boxes in 19 towns. 


A Community of Kestrel Supporters

In 2022, our efforts began modestly with three nest boxes in an attempt to learn more about local kestrel populations. In January 2023, we kicked off our first full year of the project, bolstered by the support of friends, volunteers, and birders — people who volunteered their time, money, space, and expertise, all in the name of kestrel recovery. We also received indispensable help from New Hampshire’s longtime kestrel expert, Steve Wheeler, who lent his time and expertise to the project, sharing tips on nest box construction and placement. Steve also banded all 17 chicks that hatched in our nest boxes that year.

Two volunteers construct a nest box in March 2023. (photo © Ben Conant)

Two volunteers construct a nest box in March 2023. (photo © Ben Conant)

A newly installed kestrel box. (photo © Ben Conant)

A newly installed kestrel box. (photo © Ben Conant)

Under the guidance of Bird Conservation Director Phil Brown and Steve Wheeler, former Bird Conservation Intern Will Stollsteimer developed a habitat model that identified suitable landscapes for breeding kestrels. Guided by that model, we then sought out landowner permission to mount nest boxes in priority areas. Permission in hand, we turned to the task of nest box construction.

Thanks to the generous support of community members who contributed to our “Superbowl of Birding” fundraiser, we were able to purchase materials for 21 nest boxes. In the cold of March, those boxes were constructed in a friend’s barn by a small group of kestrel enthusiasts, including a number of dedicated volunteers. With the help of another former intern, Mike Valentino, we installed the boxes and began our monitoring efforts. In the late summer of 2023, we saw the first fruits of everyone’s collective labor: 17 kestrel fledglings — banded as nestlings — left the protection of their nest boxes and burst forth into the wide world.

In 2024, the project expanded yet again, with the construction and installation of an additional 21 nest boxes in seven new towns — bringing the project total to 45 nest boxes in 19 towns, nearly half the towns in the Monadnock Region!

An adult kestrel in a nest box, surrounded by fuzzy nestlings. (photo © Phil Brown)

An adult kestrel in a nest box, surrounded by fuzzy nestlings. (photo © Phil Brown)

Bird Conservation Director Phil Brown holds a squawking kestrel nestling just after it was banded. (photo © Brett Amy Thelen)

Bird Conservation Director Phil Brown holds a squawking kestrel nestling just after it was banded. (photo © Brett Amy Thelen)

Looking Ahead

A group of four men smile with a kestrel nest box. (photo © Ben Conant)

The banding team visits a nest box. (photo © Ben Conant)

Through this project, the Harris Center hopes to increase the breeding population of kestrels in the Monadnock Region and to highlight the importance of high-quality habitat for kestrels and other wildlife of open lands. The project has already sparked tremendous engagement with landowners and has the potential to involve entire communities in kestrel conservation. Long-term monitoring efforts, including banding nestlings, can yield data related to kestrel longevity, nestling survivorship, nest site fidelity, and conservation of this iconic grassland species.

In the future, our efforts will focus on installing more nest boxes in suitable locations, continued monitoring of the nest boxes in our network, and affixing transmitters to young birds.

Contact Us

For more information on the Harris Center’s work to support breeding kestrels, please contact Phil Brown by email.