To get up to date you can scroll down to the posting from July 18. That entry tells about the camera set up, etc. These pictures are from me sitting on the couch in the living room and pointing my camera at the TV.
The 5th and last egg was laid on July 18 so we expected the eggs to hatch on July 1, 2, or 3. During the incubation period only the female sat on the eggs. During the day the temperatures were in the mid 80's and she would leave for 15-30 minutes at a time approximately every hour. She would be on the nest all night every night from dusk to dawn. The male during this time was often nowhere to be seen.
About noon on Thursday July 2 the mother left long enough for us to see one egg cracked open and a tiny pink bluebird baby struggling to get out. While the first baby was trying to break out of the shell the mother hung on the outside of the box and watched. About 3pm there was another baby and about 6pm we saw a third.This morning (Friday July 3) at about 7 am I noticed a 4th had hatched. He/she must have just hatched because the few feathers that they have at birth were still wet and sticking together. Within an hour the feathers dry and are just a little bit of fuzz around their eyes and back. As you can see in the picture below, they are pretty much pink and featherless. They have large unopened eyes and wide, large mouths.
Once the eggs start to crack open from the baby pecking on the inside, the mother helps by chipping away at the crack and making it bigger, but she lets the baby break out most of the way on its own. The mother then eats the entire egg shell. She doesn't feed the baby right away, but rather settles back down on top of the babies and the remaining eggs. You feel like she might smother them but obviously they can breathe just fine through the nest.
About an hour after the first baby hatched the mother left for about 15 minutes and returned with something to feed the baby. The male then began bringing food to the mother by hanging on the outside of the box and passing food in to her. She passed the food on to the babies. Later in the day the male began bringing food directly to the babies when the mother was gone. If he was in feeding the babies when she returned, she would wait on top of the box until he left.
When the female was sitting on the babies and unhatched eggs and the male came to the opening, we could hear a chirp or two. We couldn't be sure but it seemed to be the male making the sound, maybe announcing food was here.The food being brought to the babies appeared to be small worms, similar to mealworms, and several spiders. The babies often have a hard time swallowing all the legs of the spiders.
When the parents are away from the nest the babies mostly just lie face down apparently sleeping. When one of the parents comes with food one or more of the babies jerks their head up and opens their mouth hoping for food. For the most part they seem very feeble and can't move around much more than to lift their heads.
Here is an update on two other bluebird boxes. Another bluebird pair in my backyard completed a nest in another box about 2 weeks ago. However, no eggs were laid and we often saw the male singing in a nearby tree, apparently calling for the female. We figured that the female must have been picked off by a Cooper's Hawk or some other predator because we didn't see her for that two weeks. So I took the nest out of the box hoping that the male would find another female and she would build a new nest. I left the nest on the ground near the box so if he found a new girlfriend that she could reuse some of the nest building materials. Well, 2 days after I removed the nest there is a new nest in the box. I will check for eggs in the next couple of days.
Bad news for a friend's bluebirds. His box was on the same timetable as mine that just hatched...4 or 5 eggs waiting to hatch. A couple of days ago he called me over because he saw what looked like part of a nest under the box. When we opened the box, sure enough the nest was gone. There were muddy raccoon track on the black predator guard. A raccoon had climbed up and reached in and pulled out the nest and the eggs. We don't know if it got the mother or not. She would have been sitting on the eggs at night but she might have flown when she heard the raccoon climbing up the pole. Why didn't the predator guard stop the raccoon? My friend had wired the bottom of his predator guard so it wouldn't wobble in the wind. However, the wobble part is what is supposed to keep the raccoons from climbing. He has since removed the wire and restored the wobble. If the mother escaped she might rebuild a nest and start over. That happened when a snake got my eggs a couple of years ago. I highly, highly recommend properly installed predator guards for your bluebird boxes.
I will provide another update in a couple of days.
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