Bob Mount: How to give a bluebird the perfect home

For two or more weeks bluebirds have been searching for suitable places to nest.

Most bluebirds nowadays construct their nests in nest boxes erected for their use. They prefer boxes in relatively open situations, but ideally where a shade tree will protect them from mid-summer afternoon sun. In the absence of such protection, usually the birds can produce only a single brood, whereas they may otherwise succeed in bringing forth two or even three broods per season.

People interested in erecting bluebird nest boxes should avoid boxes constructed from treated wood or cedar, except for weathered cedar from which the strong odor is no longer detectable. The chemicals used as wood preservatives are toxic to the birds.

Among the predators of bluebirds are house cats and rat snakes. A metal shield on the post three feet below the box will deter these predators.

Fire ants sometimes discover the young and will kill and consume them. Colonies situated within 50 feet of the boxes should be eliminated, preferably using bait recommended for such use.

If boxes are situated in close proximity to forested areas, bluebirds may have competitors for the boxes, as they may be desirable for nesting by Carolina chickadees, tufted titmice, and even flying squirrels.

More information on bluebirds and how boxes should be constructed is available from the Alabama Department of Conservation and Natural Resources, Nongame Wildlife Section, 64 N. Union St., Montgomery, AL 36130 (phone no. 334-242-3469).

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It’s time to provide Carolina wrens places to nest. They are not at all particular about nesting places, but unless you provide them places you’d prefer they nest, they will place their bulky nest where you wish they had not -- in your barbecue grill or hanging flower basket for example. I place an empty coffee can on top of the pillar under my carport and an empty 12-by-12-inch cardboard box on a piece of furniture beneath the overhang of my deck.

The males, who apparently select the nesting sites, are beginning to issue their mating calls, “tea-kettle, tea-kettle, tea-kettle,” so get ready.

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I haven’t seen any humming birds yet. They usually show up around my place about the time red buckeyes begin to bloom, which should be within the next two weeks or so. Clean and rinse your feeders thoroughly and fill with a solution of one part sugar and four parts water. Do not use store-bought colored solutions.

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An interesting report, written by Justin Nobel, appeared in the March-April issue of Audubon magazine. He cites statistics showing that since 1966, the ranges of nearly 60 percent of the 305 North American bird species have shifted northward.

He also notes that during the same period, the average temperatures in the continental U.S. have risen more than 4.5 degrees Fahrenheit. Rush Limbaugh obviously doesn’t subscribe to Audubon.

Bob Mount is emeritus professor of zoology and entomology at Auburn University and writes a weekly column for the Opelika-Auburn News.