Ontogenic sequence of eastern bluebirds, Sialia sialis, from hatching to fledging. These beautiful songbirds nest in my yard every spring, and this year I wanted to record the process by taking a photograph every day as they grew. Bluebirds are very tolerant of humans, but even so I was careful to not disturb them, and since we have a slotted box (rather than a circular opening box), it was easy to slip my phone in and check up on them unobtrusively.
It is truly fascinating to watch, on a daily basis, the ability of nature to convert insects and worms so elegantly into feathers, bone and flesh.
Found across the eastern half of the United States and in parts of Mexico, the Eastern Bluebird is a small member of the thrush family. They eat fruits and insects, dropping down on their prey from low branches. Females build nests in tree cavities or nest boxes, sometimes building at multiple sites, but only using one. Eastern Bluebird populations have been rising in the past four decades, after introduced species such as House Sparrows and European Starlings outcompeted them for nesting sites in the early twentieth century. Nest boxes have been an important part of this recovery. They are the state bird of New York and Missouri.
It’s a twofer! In the trees overlooking a grassy area near the water, on the left, we have a male Eastern Bluebird, Sialia sialis, a common species, but one I don’t see a ton myself.
On the right would seem to be a House Finch, Haemorhous mexicanus. House Finches come to our feeder frequently, but I often see them with more widespread red coloration on their heads and shoulders. Apparently the color and spread of this coloration, which is limited to adult males, depends on the birds’ diet- the red is derived from the berries they eat. That’s a new fact for me!
I remember the Zip-A-Dee-Doo-Dah Zip-A-Dee-A song from Disney back when I was a kid. Part of it went “Mister bluebird on my shoulder It’s the truth It’s actual Everything is satisfactual”
It makes a day seem special when one comes by because they are not a normal yard bird for us. Scientific stuff Sialia sialis Male Eastern Bluebirds are a brilliant royal blue on the back and head, and warm red-brown on the breast. Blue tinges in the wings and tail give the grayer females an elegant look. The Eastern Bluebird is a small thrush with a big, rounded head, large eye, plump body, and alert posture. The wings are long, but the tail and legs are fairly short. The bill is short and straight.
They feed by dropping to the ground onto insects or, in fall and winter, by perching on fruiting trees to gulp down berries. Bluebirds commonly use nest boxes as well as old woodpecker holes. Source - Cornell Lab of Ornithology. Photo taken at Rondeau Provincial Park.