Kestrels Nesting at Hauser Preserve

Weantinoge is extremely lucky to count Art Gingert among its volunteers. Art has installed four nesting boxes on Weantinoge preserves. In July 2019, kestrels nested in the Hauser Preserve nesting box for the first time! Kestrels nest in cavities but lack the ability to excavate their own. They rely on old woodpecker holes, tree hollows, and rock crevices, but they will readily take to nesting boxes if they are properly situated. Male kestrels will identify several options to show the female and the female kestrel will make the final choice.

The American Kestrel (Falco sparverius) is North America’s smallest falcon and a beautiful dynamic bird. You can spot kestrels along the edges of open fields, where they hunt for their prey of insects and small animals. Kestrel populations have declined because of land clearing that removes the dead trees they favor for nesting, vanishing meadow habitat, and increased pesticide use that kills their prey. If current trends continue, the kestrel population could decrease by 50% by 2075. What will help kestrels thrive into the future? Protecting land from development, maintaining open meadow habitat for them to hunt, and thoughtfully placed nesting boxes to replace dead trees lost to clearing or windstorms.

The first indicated that kestrels had nested was on June 23, when Art visited and found a clutch of five eggs. Kestrels incubate their eggs for 26 to 32 days. After hatching, the nestlings will spend 28 to 31 days in the nest. When we returned in mid-July, only two of the eggs had hatched, the nestlings were both females and Art banded both. Banding nestlings is a way to help study the populations of birds. Art identified several clues that suggest these were young kestrels, perhaps even first-time parents.

  • It is not uncommon for younger adults to raise only two, or three nestlings, after starting quite late too. Perhaps it takes them longer to find unclaimed nesting sites.
  • The nestlings were young for mid-July, these parents got off to a late start.
  • They also had to evict other birds before nesting. They nested atop a trampled starling nest, and there were also six abandoned, undeveloped Eastern bluebird eggs in a small nest cup in a corner of the box.

Last July’s successful nesting of kestrels at Hauser means that we have had successful fledging of young kestrels from each of the four Weantinoge nesting boxes. Art says, “The only frustrating thing is that kestrels are still declining and threatened, and we are not likely to have them in residence each year even at high-quality habitat sites like Whippoorwill Farm and the Blass pasture.” We’re hoping that they return this summer.  At Hauser, hikers can use binoculars to watch the nesting box from the walking path along the north side of the meadow. Click here to learn more about this preserve.

Background on Bird Banding

The U.S. Fish & Wildlife Service administers the nationwide bird banding program, headquartered at the Patuxent Wildlife Research Center in Maryland. It’s a program that dates to the 1920s.  All banders apply for a permit and are required to submit their reports of banded birds annually. Placing numbered aluminum bands on the legs birds has provided fascinating, and important, information about the age, distance traveled, and site fidelity of birds over many decades. In fact, J.J. Audubon placed tiny silver wires on the legs of eastern phoebes at his small farm in eastern PA and watched to see whether any of the birds returned to nest in the same area (they did). Art has been banding birds since 1974 when he was a wildlife sanctuary manager and biologist for the Miles Wildlife Sanctuary, now the Sharon Audubon Center. In 2019, Art banded 149 kestrel nestlings in 26 Connecticut towns!

The U.S. Fish & Wildlife Service administers the nationwide bird banding program, and if you find a banded bird (dead or alive) you can report the band number online, and receive an official document telling you what species of bird, where it was banded, by who, how old the bird was.