Maine Natural History Observatory

Censusing and Monitoring the Species and Habitats of Coastal Maine

Maine Nest Box Monitoring

The Maine Nest Box Monitoring Project

The Maine Natural History Observatory is launching new nest box monitoring efforts and we need your help!

Each spring, Maine experiences an influx of hundreds of migratory breeding birds, many of whom utilize cavities for nesting sites. Our state, with its rich mosaic of different habitat types, provides suitable breeding grounds for a variety of cavity-nesting species ranging from songbirds to raptors to waterfowl. Cavities include naturally-occurring sites such as the chambers drilled out by woodpeckers or hollows formed in trees after a branch breaks. Suitable sites also include man-made nest boxes designed to meet the requirements of a specific species when installed in appropriate habitat. These nest boxes present a unique opportunity for observers to gather detailed information about the breeding status of these birds while providing nesting opportunities where sites may be limited.

Although many cavity-nesting species are currently increasing in number, some species such as the American Kestrel, Tree Swallow, and Purple Martin are experiencing declines in Maine. Habitat destruction and competition from invasive species like the European Starling and House Sparrow for suitable nest sites pose threats to cavity-nesting species. All the while, climate change threatens to exacerbate this issue of nest cavity competition by favoring the aggressive invasive species, which remain on or near their breeding grounds year-round, while disadvantaging non-resident individuals that migrate to reach their breeding grounds.

The Maine Natural History Observatory is beginning such a monitoring effort starting during the 2019 breeding season. This first season of monitoring will focus on three native bird species - American Kestrel, Eastern Bluebird, and Northern Saw-whet Owl. The goals of this monitoring project are to gather information about the status of Maine’s cavity nesting birds, confirm breeding for elusive species (such as owls), and to increase availability of suitable nesting sites for these native species. To accomplish this work, we are seeking the help of volunteers from around the state to deploy and monitor nest boxes throughout Maine during the 2019 field season.

We include plans for simple designs for some starting nest boxes which can be built by anyone with rudimentary carpentry skills. These designs can be modified to suit the wood you have available. If you lack the space for building your own nest boxes, we are offering some ready-made nest boxes for free, courtesy of a small grant from the North American Bluebird Society and a lumber donated by Hammond Lumber. These nest boxes are available without cost until our supply runs out. Donations are welcome and will allow us to produce more of these nest boxes in the future to make available free of charge to others just starting out with deploying nest boxes. You should be prepared that your first nest boxes may be ignored by breeding birds. Give the birds some time to find your box, but if your box remains unused after a couple of years, it is worth moving the box to a new location.

Want to take part and monitor a nest box?

We have a number of nest boxes on hand which are available for project volunteers on a first-come-first-serve basis. Contact Logan Parker (, Maine Natural History Observatory Assistant Ecologist for more information.


Click the links below to obtain copies of the nest box monitoring data sheet and handbooks:


Photo by L. Shaull