If you are a backyard bird watcher and appreciate attracting birds to your yard, consider installing a nest box or nest platform as an income-free rental. Your rewards will be watching a new family grow, some potential pest control or close-up insights into the lives of birds.
Like birds, nest boxes come in a variety of shapes and sizes. The traditional wood box with a hole in it is designed to mimic a nest cavity in nature. Many of these sites are created by woodpeckers, excavating an entrance hole and gourd-shaped cavity in which they lay their eggs. Usually created in a snag or dead branch (easier work than a live tree), the woodpeckers may use this nest site for a season or more, but it sometimes becomes available to other birds known as secondary cavity nesters.
These birds, like western bluebirds, tree swallows, house wrens, kestrels, pygmy owls and others generally donít excavate their own cavities, they use those already created by woodpeckers. There are over 80 species of birds in North America that use cavity nests; some of these are waterfowl like wood ducks, goldeneyes or mergansers or owls.
Depending upon the species that you might be attracting to your yard, there are size-appropriate boxes to put up. Introduced species like European starlings or house sparrows might take a little vigilance to keep from using the boxes, and these birds can be very aggressive towards native birds and drive them out of a cavity. The same holds true for some native U.S. species, the competition for nest holes can become intense especially where they are scarce. Also, you'll want to focus on species native to your area; there are a lot of cavity nesters that might only migrate through an area or don't occur in that region at all.
Another choice to weigh is to either purchase one or build your own birdhouse. The store-bought ones may be simple affairs or creative craft projects. The birdíes may not care about the exterior so much, but select the box for proper placement and size of the opening. Some state wildlife agencies sell pre-made kits that just need some simple assembly and are pretty straight forward boxes. For those with a few tools and a little DIY ingenuity can easily make a nest box.
There are plenty of plans on the internet that show dimensions, opening sizes and how to assemble the box for easy access when cleaning or to check on the occupants. The Cornell Lab of Ornithology ís Nest Watch site is a really good resource (nestwatch.org) for building plans, placement information and how to manage the nest box. They even encourage participants to submit data on nesting attempts for a citizen-science project. Not to forget technology, there are directions for installing a nest box camera and downloading images or video to your television or computer.
If you are ready to build-it-so-they-will-come,Image there are a few simple things to consider. Use untreated wood (pine, cedar or fir) so the box can breathe and install a sloped roof to keep the interior dry. A few drainage holes in the bottom will ensure that moisture has an escape route. The interior side of the walls should be rough or even have some metal hardware cloth stapled to it so the nestlings can climb up and exit the box when they are ready to fledge. Also, attaching the roof or one of the side walls so that it can be lifted or moved to provide access to the interior will come in handy for cleaning the box.
Height, attachment or concealment, these attributes may influence who or if the box is used. Most birds like some concealment or protection for their nest sites, but tree swallows or violet-green swallows might want a more open approach to the nest opening.
Nuthatches and flickers may attempt to create a nest cavity on the side of your house, but installing a nearby nest box might be the solution to avoiding damage to your siding.
Not all bird houses are the traditional four walls, roof and a floor. Barn swallows build a half-bowl shaped nest. Attached to a rock wall, bridge or carport ceiling, the open topped nest is protected by its difficult to access location. An artificial nest made from a cut bowl or built with short walls can be attached to a board and then the board is attached to a protected location. Though some folks donít like piles of feces that build up below the nest, remember that a lot of mosquitoes and insects went into this production.
There are also nest platforms for robins or phoebes. These C-shaped structures offer a protective location and are best placed beneath an overhang. I've seen robin nests built on top of porch lights or in the open joists of a carport.
If you have some acreage to your property and maybe stock ponds nearby or thick woods, there are larger nest platforms that can be installed to attract great horned owls or great gray owls, while building a platform in an old barn may attract barn owls. These predators will help reduce rodent populations, but don't forget to keep the cat indoors or they, too, could become prey.
So depending on what species you want to attract to your yard, there is a nest box to match. A quick search on-line will provide plenty of websites for you to visit and review the types of boxes and how to build them. And remember, if you build it, they will come; it might just take a season or two for the birds to find their new home.