Keep monitoring! It is absolutely critical that we receive information on all nestboxes: if partners don’t report boxes that are unoccupied, our data reflects higher occupancy rates than there actually are. We know how discouraging it can be to work hard on a nestbox and see it go unused, but information on where kestrels aren’t is just as valuable as information on where they are. If kestrels aren’t using your boxes we need to know why, and observations from unoccupied boxes are our best clues.
Also, stay patient. It often takes kestrel pairs a year or two to move in, so keep the box up and see what happens. You might try building new boxes and placing them in other spots near the original, to see if different locations, entrance orientations, mounting surfaces, etc. are more attractive to nesting pairs.
Finally, take advantage of our partner network! If kestrels aren’t moving in to any of your boxes and you would still like to visit an occupied nest, try contacting a fellow American Kestrel Partnership researcher in your area to see if they would be willing to take you along on a monitoring visit. This is exactly the collaboration we hope to facilitate through the Partnership, and the visit might give you insight into how you can better attract kestrels to your own box(es).
If non-kestrel species use a nestbox, please report this to us just as you normally would. Again, data on boxes that are not occupied, or are occupied by other species, are absolutely critical to our research. We also encourage you to register the box with the Cornell Lab of Ornithology’s NestWatch program, which collects nesting data on all bird species.
As European Starlings are an invasive species, many nestbox programs remove their nesting material and eggs from boxes to curb nesting competition. However, we recommend that partners do not interfere in this way, since we are investigating nesting competition and can only do so with information on breeding starlings. If you do choose to remove starling nests, make sure to record this.
Please note: it is illegal to remove or destroy the eggs, feathers or chicks of any species covered under the Migratory Bird Treaty Act (starlings are not protected under this act). Non-kestrel species will sometimes use kestrel boxes, but please do not remove them. Tell us about them instead!
Look around for hunting territory. Is there plenty of low vegetation nearby? How many rodents and insects are found in the area? How many trees are nearby? (kestrels need hunting perches, but avoid heavily forested areas). We also suggest placing nestboxes at least 6-7 feet off the ground, in an area with relatively low human activity.
Do not leave food out for kestrels. You could attract kestrel predators instead.
Researchers and citizen scientists have been building and monitoring kestrel nestboxes for decades, and in the decades of data generated, there is little to no evidence of adults abandoning nests once eggs are laid because of brief, periodic nest checks by humans. However, monitoring can disturb nesting kestrels if it is undertaken carelessly, so make sure to always keep nestbox visits short.
No permitting is needed to monitor nestboxes, since volunteers must only peek in to count the number of eggs and nestlings. If you plan on any activities that involve touching the birds, however (e.g., banding nestlings, weighing nestlings, or collecting DNA samples), you must apply for permitting under the Migratory Bird Treaty Act. Please contact us for more information.
Although kestrels don’t typically hunt songbirds during the nesting season, small birds do know that the falcons are a threat and will avoid areas that they frequent. If you enjoy watching birds on a particular feeder we recommend placing your kestrel nestbox either out of sight or a small distance away.
We also receive questions about how to ensure that kestrels don’t eat feeder birds. While this happens infrequently, it is a possibility—keep in mind that kestrels and songbirds alike are wild species that rely on predator-prey relationships. Kestrels must make a living, and by putting up feeders we invite their prey to visit us. It is natural and healthy that prey species arrive with a few predators in tow.