SONGBIRD NESTING BOXES by Kristin Belair
This article originally appeared in the Summer 2026 Napa Valley Chapter CNPS newsletter.
A huge thank you to the Napa Valley Community Foundation for their generous grant supporting Habitat Conservation and Development for Local Wildlife. The Napa Valley Chapter of the California Native Plant Society put these funds to use to purchase 10 Songbird nest boxes, a barn owl nest box and a raptor perch from Aloft Napa Valley (Tom Clark aloftnapavalley.com). And thank you to Darin Cravea, director of Skyline Park, for organizing Tyler to help with the very important task of getting all the pieces installed.
Songbirds are in decline for a wide variety of reasons, including habitat loss. Providing nest boxes for cavity nesting songbirds can increase the chances for successful reproduction and as we have seen in vineyard locations, if you build it, they will come.
The nest boxes were installed at the end of May, so it is unlikely they will be inhabited this season since nesting season starts in March, but we may get lucky and a pair might go for a second brood. Six of the songbird nest boxes were installed throughout the Martha Walker Garden and four of them, along with the barn owl nest box and raptor perch, were installed in the growing grounds near Becky’s Garden.
The songbird nest boxes have been numbered, and we’ll be cleaning and monitoring them every fall, after nesting season is over. Because the nest characteristics will vary by what species of birds built it, we can tell who the occupants might have been and, by looking at the nest, if there were chicks that fledged.
The following bird species may use the nest boxes: Western Bluebirds, Tree and Violet-Green Swallows, House Wrens, Chickadees, Titmice and Nuthatches. It will be exciting to see who takes up residence!
Having a Barn Owl nest box in the growing grounds engages ecosystem ‘services’ for rodent control. Barn Owls typically start nesting in late winter/early spring, and a Barn Owl family can consume up to 3500 rodents a season. It is likely we will not see any occupancy until early next year. As a side note, Western Screech Owls have been known to inhabit and breed in Barn Owl nest boxes. Early next spring, we will have Napa Wildlife Rescue, through their Barn Owl Monitoring Program (BOMP), check the nest box to see who has moved in.
A raptor perch in the growing grounds may also be helpful in encouraging local raptors to hunt in that area. Keep an eye out for who might be hunting in the growing grounds. It could be a variety of hawks and or falcons.