If you love bluebirds and have a place for them, consider building some bluebird boxes. You may be able to start and maintain a whole bluebird trail on public lands or on a friend's farm.
Bluebirds like open fields. If you place the box near trees, they will have to compete with other cavity builders like chickadees, wrens, and nuthatches. In the open, where tree swallows are present, they will compete with them. All of these species can use housing, especially given the loss of habitat for them. If you put up paired boxes about five to twenty feet apart, or even mounted on the same post, bluebirds will share with another species and the four parents will be more successful at repelling enemies. A single box or the pair of boxes should be about 300 yards apart. Eastern bluebirds are put at least 100 to 150 yards apart. e
This bluebird box plan is based on the boxes for mountain bluebirds at Red Rock Lake National Wildlife Refuge. We collect data from the boxes each week, documenting whether a nest has been started or finished, how many eggs are present, whether the mother is sitting on eggs, and the number and age of the hatchlings. Our boxes are top opening, so we are less likely to cause the young to fledge early, than if we opened a front opening box. We have to make sure we have a little space at the bottom of the box to fully clean out the debris after we remove the old nest. That is why the corners are cut off. (We clean out the boxes on the visit when we document that the birds have fledged to prevent parasite buildup.)
Our boxes are on the large side because larger boxes have been associated with bigger clutches and they also help prevent overheating. We make them of cedar. The roofs tend to crack, so we make extra roofs to repair as needed. Using another material for the roof, could be another option. But I just move the wire from one roof to the next.
For more information and more plans, check out the
Mountain Bluebird Society if you have them. Or the
Eastern Bluebird Society or Western Bluebird Society, if you have those species. All of them offer plans for nest boxes.
North American Bluebird society has information on all three species.
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| Our target species |
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| A bluebird box being contested by a male mountain bluebird and a tree swallow. |
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| These eggs are either ready to incubate or the female is already incubating them. |
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| Caught this nest on hatch day. We record the age of the nestlings as zero. |
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| Tree Swallow Pair |
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| The nest of a tree swallow - the female covers the eggs with feathers when she leaves. |
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| Pieces cut out for twelve new boxes |
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| Screwing them together. |
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| The finished pile is growing |
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| The open corners in the floor lets us brush out the small pieces left after the nest is pulled out |
This is the bluebird box I took apart to show the pieces. The little 1" X 2" strip that is screwed to the back board is missing. This strip is put just on top of where the roof is so the roof is slotted into it in the back, Then a heavy wire is loosely stapled to the top of the box, the ends are bent in and pushed into holes drilled into the box sides. The hole should be 1 & 9/16". You can also add three slanted holes, slanting from bottom to top on the tops of the sides, to add ventilation. Some plans don't show the cut corners, but they really facilitate thoroughly cleaning the boxes between nestings, thus keeping the mite numbers down.
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| The dimensions of the pieces. |
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| A bluebird box in place showing the little strip and the wires that hold the roof on. |
I'm being lazy and spending the first day of my three days off laying around watching it rain. Hopefully, I'll get to go birding tomorrow, but I think I may have to wait until next Monday.
