The Wisconsin Kestrels and the New Nestbox!

The Wisconsin kestrels are back and have laid five eggs! We anticipate hatch on or around May 20 this year.

A lot of you were curious about the new nest box. Why does it look like the inside of a log? From Neil Rettig Productions: “Last year was one of the only years we didn’t have kestrels nesting at our barn. A pair was interested in the box, but the female seemed very nervous about the set-up. To our surprise, they selected a screech owl box about 200 yards from the barn, in an old apple orchard. It was a year of missing the little falcons, since they were very secretive and rarely seen.

After the kestrels fledged and the breeding season was over, we removed the screech owl box in hopes of attracting the little falcons back to the barn. After discussions with Cornell and RRP, we also decided to upgrade the kestrel box to a natural cavity. We felt it would help reduce suspicion and better simulate a natural nest.

April 18, 2024: She went into egg labor late morning...
April 18, 2024: The new nestbox simulates a natural cavity environment right down to the substrate!

We also paid attention to the substrate. In natural cavities, kestrels bite and remove bits of rotten wood that are incorporated into the nest when they shape the bowl or scrape. Pea gravel works fine, but kestrels don’t incorporate it into their nests, so we replaced it with a more typical material.

The old box didn’t sit empty last year. A very determined pair of starlings nested in it and starlings were back again this year. The new natural cavity was prime real-estate and we had an all-out fight between the kestrels and the starlings. We saw and recorded several very dramatic encounters! It was amazing to watch the behavior of the starlings and magical to listen to the vocalizations and courtship behavior of these very intelligent birds.

We didn’t want the nest to fail again, so we decided to encourage the kestrels and lure the starlings away. We placed a starling box with a 2-inch diameter hole 10 feet below the kestrel cavity, and that did the trick. The starlings took to the new box, the fighting waned, and everybody seems happy!”

Watch the Wisconsin kestrels here: https://www.raptorresource.org/birdcams/american-kestrels/ or here: https://www.allaboutbirds.org/cams/american-kestrels/