We have been fortunate to have two families of Eastern Bluebirds (Sialia sialis) raised on our property this year. They accepted our boxes and became very busy soon after arrival. This post discusses the young fledged from the nests. For other information on Eastern Bluebirds please search this blog for 'bluebirds' for 3 other posts.
Our two families of Eastern Bluebirds raised broods successfully. They both appeared to start late with their first brood (compared to the Tree Swallows). Although I am not certain, both pairs appeared to raise only one brood. One brood was later than the other so that might have been a second brood.
One group of 3 juveniles have spent their time after fledging around our yard. Although a bit wary of us, they have become reasonably accustomed to our comings and goings. We often see them sitting on stakes, trees or low bushes, flying out to catch insects or other invertebrates. They enjoy our birdbath as seen in the photo above. As the summer progresses their spots are beginning to fade and they are gradually getting bluer.
The female brooded the chicks carefully after they hatched, spending time in the box with them. Both adults fed them as they grew and finally fledged after 15 to 20 days. As the young matured, the adults have moved on. We rarely see them now. The young seem to be doing well at feeding themselves and avoiding danger. See below how well they are camouflaged by their plumage.
Eastern Bluebirds can live 6 to 10 years. Unfortunately many die within the first year of life. The young can die of starvation and freezing. Many are taken by predators and humans present a huge threat. Eggs and nestlings are taken by chipmunks, raccoons, flying squirrels, and parasites. Cats and hawks will take adults and juveniles. Humans play a role with habitat loss and poisonous sprays. Introduction of invasive species like the European Starling and House Sparrow has caused increased competition for nest sites.
We are fortunately getting wiser with better environmental protection against poisonous sprays and the construction of good bluebird houses. The placement of many of these wooden birdhouses in appropriate habitat has definitely been positive for Eastern Bluebird population numbers. Many people have reported families of bluebirds being raised on their properties this year. That is really good news! A big thank you goes out to those who have established 'Bluebird Trails' or series of bluebird boxes placed along roadsides in appropriate habitat in their areas. This is being done in New England and here and we are now seeing positive results.
We hope food will be abundant, dangers will be few and winters will be mild so that our Eastern Bluebirds winter successfully and will return next year. We love to share our land with them and enjoy their melodious warble and the flash of their beautiful plumage.
ADDENDUM
Yesterday we saw 4 Eastern Bluebird juveniles feeding in our backyard. They were perching on the clothesline and flying down onto the lawn to pick up insects. Soon we saw more and at one point saw 7 altogether. That included at least one adult. On examining my photos one can see that we have 2 age groups among the juveniles. Notice that as the young get older they begin to lose their spots, get a little bluer and begin to get the rust colour on their breasts. See the photos below.
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