An iconic, mostly North American migratory songbird, the Eastern Bluebird could currently be considered a conservation success story. I have written a few posts about the damage that invasive species and habitat destruction have on native species. Bluebird populations suffered terribly from both of these until a widespread grassroots conservation effort took hold and helped turn the tide.
Bluebirds suffered declines from the introduction and adaptation to North America of introduced European Starlings and House Sparrows. Both invasive species out competed passive bluebirds for nesting sites. Bluebirds relied on natural cavities or ones made by woodpeckers, etc. Destruction of potential nesting cavities by removing snags and replacing wooden fence posts with metal ones were two major examples of habitat destruction contributing to their decline. There can be a natural ebb in bluebird populations due to extremely cold winters, such as occurred in the south in the early and late 50's and late 70's. When bluebird populations were already greatly decreased due to invasives, habitat destruction and the widespread use of pesticides such as DDT, the survival of the species was in more peril due to natural fluctuations.
Luckily the public took notice of the precipitous decline of this pretty and melodious bird and has participated in programs aimed at helping overcome the loss of natural cavity nesting sites. The bluebird will accept artificial nesting cavities in the form of bird houses. Proper construction of the opening to the bird house can even prevent starlings from being able to hijack the nest. Check in your area for a local bluebird society that can help give you tips on bluebird birdhouse construction or check out the North American Bluebird Society webpage. One tip for putting up bluebird houses is that bluebirds are territorial and need a certain amount of space per nest. It is best to keep bluebird houses a minimum of 300 feet apart to allow enough territory for each family.
While I was growing up in the east during the 1960's and 70's small increases in bluebird populations began to be observed due to the establishment of bluebird trails and other nest box initiatives. Because I was aware of the plight of the bluebird, I was very excited when I saw my first one in the wild in North Texas almost two decades ago. I would continue to see a bluebird occasionally in a local park and then several years ago I started seeing them around my yard and pasture. One year I even got to see some newly fledged babies fly to a statue next to my pond. By the time I got my camera, two of the three had already flown off.
Every individual can make a difference in the conservation of our native flora and fauna. Through the efforts of many individuals, bluebird populations are growing again. Since European Starlings and House Sparrows are not likely to ever all be sent back across the pond, continued support by individuals is likely to be necessary for the continued success of bluebirds.
(The first image in this post is available as a matted 5x7 print. Please contact me for details if you are interested in purchasing one.)