Principles of Building Bird Houses

Building bird houses is not only a great way to spend a few winter evenings, but is also a wonderful activity for kids to participate in.  Photo by Cathy Thomas

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The change to Daylight Savings Time forced me to contemplate the long dark winter evenings ahead. I do hope to get out and enjoy some nighttime activities, but reality suggests that there are still going to be a lot of hours spent at home. Building some bird houses would be a great way to use some of that time.

Building bird houses that actually serve their purpose is not as easy as it might seem. Bird houses are used by birds that ordinarily would nest in natural cavities in trees. Each species can be pretty particular about the house they will raise their babies in.

The process of creating a useful bird house starts with deciding which species you want to attract to nest in your yard. A nest box for a wren will be very different from a box for a kestrel or even a bluebird.

Hole size is of primary importance. Birds are particular about that but there is more to it. House sparrows and starlings love to utilize boxes when they are available and will usurp any boxes that they can fit into. Sometimes house sparrows will just fill them with nesting material so other birds can’t use them. However, wrens, chickadees and other small birds can fit into smaller holes than either of these interlopers and the appropriate hole size helps ensure that the target bird will not be ousted by the pests.

Box size is also important. A box that is too small isn’t useful even if it has the right hole size and a box too large may be a trap for the nestlings when it comes time to fledge. Box sizes for a wide range of species have been determined and these sizes should be followed carefully.

A lot of people love to decorate their bird houses, making them into attractive yard ornaments. Birds may still use them (or they may be put off by the gaudiness) but the pretty features do nothing for the birds. Plain unpainted boxes left to weather are ideal. Regardless, do not paint or stain the inside—it can be toxic to the birds.

Material for bird boxes can be as simple as ¾ inch plywood, or just about anything else. Many plans ask for rough-cut lumber which is thicker than finished wood but rough-cut can be hard to find. Make sure you build those plans using the interior dimensions if you use finished lumber instead. Also, don’t use treated lumber. It is toxic and can kill your feathered guests.

Finally, there are a few other things that all bird houses should have. First is adequate drainage. Drill at least four ¼ inch holes in the bottom. The bottom can also absorb water so recess it up about ¼ inch. Second is ventilation. Houses that get too hot can kill the chicks. Leaving a ¼ inch gap between the top of the sides and the roof alleviates this. Third, make sure that either a side or a top is hinged so that the bird house is easy to clean. Fourth, roughen the inner surface below the hole so the chicks can climb out when the time comes. Also, perches are unnecessary.

So, get out the hammers and saws and make a few bird houses this winter. Do them right and you will enjoy the benefits for years to come. You can find plans to a number of bird houses on this website on the Naturalist Corner page.

 

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Wildlife License Plates

Great news! as of 2024, there are three NEW designs for license plates. They still are bluebird, cutthroat trout and elk, but they are beautiful.

Idaho Wildlife license plates provide essential funding that benefits the great diversity of native plants and wildlife that are not hunted, fished or trapped—over 10,000 species or 98% of Idaho’s species diversity. Game species that share the same habitats (such as elk, deer, antelope, sage-grouse, salmon, trout) also benefit from these specialty plates.

No state tax dollars are provided for wildlife diversity, conservation education and recreation programs. Neither are any revenues from the sale of hunting or fishing licenses spent on nongame species. Instead, these species depend on direct donations, federal grants, fundraising initiatives—and the Idaho Wildlife license plates.

Both my vehicles have Bluebird Plates. I prefer the bluebird because the nongame program gets 70 percent of the money from bluebird plates, but only 60 percent of the money from elk and trout plates - 10 percent of the money from elk plates supports wildlife disease monitoring and testing programs (to benefit the livestock industry) and 10 percent from cutthroat plates supports non-motorized boat access.

Incidentally, in 2014, the Idaho Legislature denied the Department of Fish and Game the ability to add new plates or even to change the name of the elk and cutthroat plates (very specific) to wildlife and fish plates, a move that would have allowed for changing images occasionally and generating more revenue. It would seem that they believe that we Idahoans don't want a well funded wildlife program.

I think it is time we let the Legislature know that Idahoan support wildlife funding and that we would like to see these generic plates come to fruition.