How to Build a Kestrel Nesting Box
Why Should I Make an American Kestrel Nest Box?
The American Kestrel is the smallest falcon found in North America. Once declining and at risk of extinction, the kestrel population has rebounded thanks in large part to conservation efforts including the placement of specially designed kestrel nesting boxes.
Kestrels are cavity-nesting birds, but they cannot excavate their own nest sites. Instead, they rely on finding natural cavities in old trees or the abandoned hole of a woodpecker. When natural nesting sites are in short supply, kestrels will adopt a man-made nesting box to raise their young.
The American Kestrel nest box is an easy woodworking project to make. I used inexpensive pine from the local home center. Cedar is another good choice, though it's somewhat harder to find and is slightly more expensive. Left unpainted and untreated, both kinds of wood will weather to a silvery-gray and last for several seasons.
The plans for building this kestrel nest box includes the addition of a small fledgling shelf mounted to inside of the box. The ledge lets the baby kestrels look out of the box while waiting for their parents to arrive with their next meal.
How to Build a Nest Box for the American Kestrel
The Cutting List
Cut a 1" x 12" cedar or pine board into the following parts:
- Front (part A): 11 " W x 18" L
- Back (part B): 11 "W x 24"L
- Sides: (part C) 9" W x 20" L (Qty = 2)
- Roof (part D) 11 " W x 14"L
- Bottom (part E) 10" W x 9" L
- Entrance guard (Part F) 6" W x 7" L
- Fledgling Shelf (Part G) 1 " W x 11 "
Layout the Pieces
- Cut the top edge of the sides (part C) on a 30-degree angle to create a slope for the roof. From one end, measure up 20" along one edge and make a mark. From the same end, measure up 18" along the opposite edge and make another mark. Draw a straight line to connect the marks using a ruler or straight edge, and then cut along the line. The angled side pieces are 1/4" shorter than the front (part A). The shorter sides create a 1/4 inch gap under the roof for air circulation.
- Layout the location for the oval-shaped entrance hole on the front section (part A), and then cut out the opening using a jigsaw. Kestrels prefer oval openings approximately 4" wide by 3" high. Cut a 30-degree bevel across the top edge, matching the slope of the roof and sides.
- Clip off each of the corners on the bottom piece (part E) at a 45-degree angle, creating small gaps for drainage. Using weather resistant screws or nails holes, attach the bottom section to the back and side assembly.
Assemble the Nest Box
- Line up one side (part C) to the front piece (part A) making sure that the bottom edges of both pieces are flush with other. The top of the side piece (part C) should be 1/4 inch shorter than the front piece. When fully assembled, the 1/4" opening will allow air to circulate and help to cool the interior of the nesting box.
- Attach the side piece to the front section using weather-resistant nails or screws. This is the fixed side, while the other side is hinged to allow access to the finished nest box for periodic cleaning.
- Position the Fledgling Shelf (part G) on the inside of the Front section (part A), approximately 2" below the opening.
- Attach the nest box floor (part E) to the sub-assembly.
- Position the partially assembled nest box to the back (part B), leaving space both above and below the nest box so you can assemble it to mount the finished box to a tree or pole. Attach the back to the nest box assembly with nails or screws.
- Cut a 30-degree bevel across the back edge of the roof (part D). The bevel matches the angled sides and allows the roof to fit snugly against the back (part B). Attach the roof to the back, side, and front sections.
Make A Simple Hinge
- Line up the remaining side (part C). To create a hinge, secure the side with one nail or screw driven into each edge—one through the front (part A) and one through the back (part B) to form a pivot point. Position the hinge screws directly across from each other, enabling the door to open easily. To secure the door, drill and countersink a screw hole along the center of the bottom edge. A single short screw will keep the door closed yet allows easy access for cleaning.
- Cut a 3" x 4" hole into the center of the entrance guard (part F). Round off the edges with sandpaper, or use a round over bit to create a finished edge. Mount the entrance guard on to the Front (part A) of the nest box.
- Hang the new American Kestrel nest box facing an open area such as a large field, meadow or pasture. The kestrels will thank you!
American Kestrel Nest Box Plans
Hanging the Nest Box with a Simple Cleat
This simple cleat system is easy to make, and it's useful for hanging projects such as birdhouses, cabinets and window boxes. The cleat is made by ripping a piece of stock at a 45-degree angle.
- Start with a piece of wood at least four inches wide, and slightly shorter than the width of the nest box. Tilt the table saw blade to 45 degrees, then set the fence to 2 " from the blade to rip the stock into two mirror-image pieces, each with a 45-degree bevel cut along one edge.
- Attached one of the pieces to the back of the project with the 45-degree angle of the cleat pointing downward to form an inverted "V" between the back of the feeder and the outside surface of the cleat.
- Attach the second piece where you want to hang the nest box, this time with the "V" of the cleat facing upward. Use weather-resistant screws, and make sure the cleat is level.
- When fitted together, the two 45 degree "V"s from each piece lock together to securely hold the nesting box in place.
- Add a filler strip along the bottom edge of the nest box, below the cleat on the backside, to hold the nest box upright and plumb. Cut the filler strip to the same thickness as the cleats.
Have You Ever Seen A Kestrel?
Certify Your Backyard Wildlife Habitat
The National Wildlife Federation Certification Program
For over 35 years, the National Wildlife Federation (NWF) has encouraged homeowners, schools, corporations and municipalities to incorporate the needs of the local wildlife into their landscape design.
So far, the NWF has recognized the efforts of nearly 140,000 individuals and organizations who plant native shrubs and plants for food, cover and places for raising their young, provide include a source of drinking water, and add nesting boxes for cavity nesting birds.
Our property is a certified National Wildlife Federation Backyard Habitat that provides shelter, nesting sites, fresh drinking water and year-round food supplies for the birds, deer and other local wildlife. Kestrels are seen occasionally, and we hope that a pair will move into our kestrel nesting box to raise a brood of chicks.
Questions & Answers
© 2012 Anthony Altorenna