Backyard Bluebirds -- Part One

Back in the sixties and seventies, my dad always set up nest-boxes in the spring to try to attract bluebirds. I never paid much attention to this; I was often too consumed by school and sports-related endeavors to think about much else. I wasn't even sure how successful (or unsuccessful) he was until many years later.

My interest in birding, and bluebirds in particular, began in early 2006. I was familiar with the common backyard birds: Robins, Cardinals, Chickadees, Blue Jays, etc., but knew very little about slightly more unusual species. A new digital camera and chance encounters with a Bald Eagle and a hawk whetted my appetite to find out about other birds. In spite of my Dad's history with bluebirds, I had no recollection of ever seeing one myself. In the early spring of that year, I spotted a flash of blue in our side yard. I snapped a quick picture of it. When I reviewed the photo, I realized I had seen a male Eastern Bluebird.

Seeing my first real, live bluebird made me want to try to attract a nesting pair. I bought a small unfinished bird house for $3 at Michael's, of all places. After brushing on some varnish, and slightly enlarging the entry hole, I attached it to a piece of pipe and put it up in a wooded area in my backyard. I didn't realize, at that time, that this was a poor location for bluebirds, who normally prefer open places. I managed to attract only a house wren, who proceeded to build a nonactive (dummy) nest in it.

During the following winter, I downloaded some plans for a bluebird box, and then built the box from a single 6-foot long, 1x6 inch board. In early March of 2007, I started seeing bluebirds on the more open side of my backyard. So around the middle of that month, I bought another piece of galvanized pipe, and put up the new nestbox in that part of the yard.

I almost immediately began seeing a pair of bluebirds. They would sit above the box, and occasionally land on it or go in it. Their courting ritual includes the male picking up some dried grass or twigs and placing them in their prospective home. If the female approves of his choice, she will then enter the box or tree hole he selected. I watched this played out several times, so I was pretty sure they were going to use my nestbox. To add additional enticement, I made a mealworm feeder out of a broom stick and the bottom of a 2-liter plastic bottle. After I stocked it with mealworms from a local pet supply store, both birds quickly found it. They would empty it almost as fast as I could fill it!

The nest-building building process was excruciatingly slow. The first couple weeks after the courting display resulted in only a small amount of nest material being deposited. I suspect the cool weather caused the female to delay starting the nest in earnest. After about 12 days of activity, the nest appeared complete. During this period, the bluebird pair survived some bullying by robins, and frequent challenges by house wrens. To counter the house wrens, I set up another box about 25 feet away for them to use. Fortunately, there were few sightings of house sparrows, bluebirds' mortal enemy.

The female laid one egg a day for the next 5 days, and then started incubating them. She spent less time actually on the eggs than I expected, with frequent exits for a quick fly and to look for food. She consumed many of my mealworms, but also had to spend some additional time hunting. The male, who had actively defended the nest during its construction, seemed to disappear for a few days after about the 3rd egg was laid. He then returned, but this seemed like the start of a pattern of frequent disappearances and reappearances.

After about 13 days of incubation, the five young bluebirds hatched. They were mostly bald with just some fuzz on the top of their pea-sized heads. They were tiny and mostly helpless at hatching. The female, and occasionally the male, fed the young almost constantly. My mealworms were still their favorite snack!

The baby birds started getting their pin-feathers after about a week in the nest, and were starting to look like real birds. I opened the nest at least daily, and examined them. The mother was not afraid of me, and pretty much totally ignored me.

Unfortunately, things started going wrong a little over a week later after hatching. June 8, 2007, was the hottest day yet of the summer, with the temperature hitting 88F degrees. That afternoon the adult bluebirds seemed to become listless, sitting lazily in the tree near the nestbox. After that point, unfortunately, I never saw them feed the young again.

Late that evening, we had a severe thunderstorm. The next morning, when I checked the nest, it was apparent that neither adult had visited it because the babies were hungry, and the fecal sacks had not been removed. Also, all the mealworms I had put in the feeder the previous night were uneaten. I was pretty sure something was seriously wrong. The father bluebird did return during mid-morning, but just scarfed up the uneaten mealworms while the babies cried, just a few feet away.

I finally decided to call our local wildlife rehabber around noon to report that the chicks had been effectively abandoned. While on that call, I was relieved to see the female bluebird return and sit on top of the bluebird box. I told the rehabber that things were probably okay after all, and I terminated the call. But, unfortunately, the mother never entered the box, and quickly flew away.

The male was around most of that day, but made no attempt to feed the young. A couple of the nestlings came forward to the front of the box, and could be seen through the hole. I tried to toss in some mealworms to them, but they wouldn't eat anything without the parents present.

The next day neither of the adults were present, and some of the babies continued to look out the hole and cry. I vainly hoped that the babies were older than I thought, and might be trying to fledge. When I looked in the box, though, it looked like the others were compressed into the bottom of the nest, and possibly dead. I decided to let nature take its course.

The next morning, all the nestlings were dead. I removed, weighed, and buried them. A day or two later, I saw the mother again briefly, and saw the father several times. He appeared to be doing "phantom" feedings: pushing a moth through the front of the hole as if the babies were there. Very bizarre!

My theory is that the adult bluebirds were first-time parents, and didn't completely know what they were doing. The heat and storm may have pushed the mother over the edge, especially given that the male was a largely ineffective father. When I told a couple other birders and bluebird experts this, they basically laughed at me. They said that a hawk or predator must have gotten the parents, or at least the mother, and the adults I saw after the storm were different bluebirds. I think this is highly unlikely because bluebirds are uncommon here, especially in mid-summer. The orthodox blue-birders seem to think that the birds are robots, whose actions never deviate from the mean.

I suspect that there is considerably variation in birds and animals, much like there are ineffective mothers and deadbeat dads in humans. I doubt that many of the bluebird experts and trail-owners are able to watch a pair of bluebirds as closely as I did. To them, I think, all bluebirds fit the norm (or at least average).

This initial failure caused me to become more determined to have a successful nest. I'll wrap up this installment now, and report on my later attempts in the next installment.