Tree Sparrow Male-Female Cooperation and Strangeness in NB-4

Unfortunately I am not abel to follow the events which might be unfolding in NB-3 (it being at work).

I have however discovered to my great surprise, that not only do the Tree Sparrows bild the nest together, they also take care of the eggs together. I am unsure as to whether both female and male brood (the nest construction had seriously limited by optical access) but at least they take turns at being in the nest.

I just noticed that one of the Tree Sparrows entered the nesting box, chirped, there was then a serious chirp-conversation and then the bird in the nest left to be replaced by the other that had just entered. This second bird then gave one quick peak out of the nesting box and then returned to the nest.

What I find really funny is that when it entered the nest and adjusted itself, it chirped a bit until it had settled. Sparrows are indeed completely different to Tits in their behaviour both as individual birds as well as in pairs. They are definitely more "outspoken".

Now a little update in NB-4: the female Great Tit spends her days in the nest. I am not sure what is going on, and I wonder if for some reason she is unable to lay eggs. I cannot image that she is simply the whole time just sitting there, guarding and empty nest. Then again, there might be the possibility that she had indeed laid eggs and that these are incredible well hidden. This would however surpise me because it would imply that she broods without uncovering the eggs, which is altogether very strange. Her first night in the box was the 22nd of April and by now she should have laid more than enough eggs really. If I assume 10 eggs, this would lead to the 2-3rd of May, so in theory she would now be in her 3rd day of brooding. The male Great Tit still feeds her regularly. I am curious as to how this will all evolve.

It was about 8:15 when I noticed the Tree Sparrows switching places. At 8:32 they switched again. Now again, I wonder: on the 26th of April, one of the Sparrows, spent the first night in the nest (I presume the female, but I may be 50% wrong! which is a huge error range in my books :-)) now again: on the 26th the first egg might have been laid, by now there should be a sufficient number of eggs in NB-1. Given this switching, I presume that now brooding has indeed begun. Previously, I had noticed that there were gaps of time in which no bird was in the nest. If this is so, i.e. brodding, then (assuming ca. 8 eggs) then brooding has started ca. 3-4 days ago and thus there are still 2.5 weeks to go until I hear tiny high-pitched chirping.

One this is sure: I am going to have to conceive a new nesting-box concept with which I am easily move my camera(s) around (perhaps finger cameras?). I am thinking hard already. As soon as the season is over and the birds have left (such that I have gathered enough information to know how the different phases: nest building/egg laying/brodding/hatchlings, modify my optical access requirements) I will start developing version 3 of the nesting box.

Food Priorities

16:50 pm: the male seems to be enyoing feeding the hatchlings himself. He entered the nesting box with a tiny worm whilst the female was inside. She asked that the worm be given to her. The male clearly did not want to comply and he simply left the nest. He flew to the tree nearby and waited. After a couple of seconds he returned. The female was at the entrance hole so he left again. After the female left he entered the nest and fed the hatchlings himself.

5th Hatchling....

16:23 pm: I noticed a hole in a 5th egg.....the 5th hatchling is on its way!

4th hatchling!

13:46 pm: 4th hatchling. The female helped it hatch and then removed the egg shell from the nest.

4th hatchling -> 3rd hatchling!

13:28 pm: another egg has just cracked open along the middle line. So the fourth hatchling has now become the third to come out! The 4th with the hole is still struggling. I wonder how the come free. I have the feeling that if the egg cracks along the middle-line it is a much faster process in comparison to the hole-process. The female has just carried out one half of the egg shell.

3rd Hatchling still "hatching"

13:22 pm: The male Blue Tit entered the nesting box and fed one of the two hatchlings. He then noticed the hole in the 3rd egg and inspected it carefully. He remained in the nest and observed the hatchlings until the female returned at which point he left to get a worm. The hole in the 3rd egg is now larger. It has been at least 2 hours now. With the last hatchlings it took at least 3 hours before it had freed itself from the egg shell. The hatchlings can be heard: a tiny high pitched chirping. The male again entered the nest after the female left. I wonder if this is his first batch of hatchlings. He seems to be a bit unexperienced and he takes enormous care at making sure that his feet are outside of the inner nest where the hatchlings are. The difference in behaviour between the male and female is significant. Fascinating!!

3rd Blue Tit Hatchling!

12:07: #2 hatched ca. 30-40 minutes ago. There is a hole in a 3rd egg, so there will be 3 soon...!!! :-)))

12:10 pm: The female Blue Tit returned, noticed the hole and pecked a bit at the egg.

Mother Warmth

10:13 am: the Mom Blue Tit left the nest again a couple of times to feed the 1st hatchling. When she returned the 3rd time the hatchling did not respond to the extended feeding calls so she ate the mini-worm herself. She then sat on the eggs and hatchlings. The Papa Blue Tit came by just seconds after with a worm and chirped to signilise that he was there. The female responded but did not get up. He left, flew to the tree and then after a couple of seconds flew back and again chirped. Again she did not get up. He again flew away and flew back but again she did not get up. He then left. So..., the female knows that she must not get up and let the hatchling cool down too much even if food is awaiting. Fascinating!

10:18 am: After 5 minutes of warming up, the female Blue Tit had just left. I see her flying around in the tree near by looking behind leaves and such..

10:19 am: the male has just fed the female in the tree.

10:20 am: the male flew to the entrance chriped but left. For some reason he does not enter the box. I wonder if the entrance hole is too small.

10:21 am: the female returns, enters. the male returns to entrance hole. The female inside has a small worm in her beak. The male at the entrance a larger worm and calls to her. The female is now torn between feeding the hatchling and taking the worm from the male. He notices that something is amiss and enters. She hesitates and then hatchling lifts its head and opens its beak. The female feeds the hatchling and then takes the larger worm from the male. She eats it herself. He leaves. Somehow the male always pulls on the worms when the female tries to take them from him. This is new of this morning. I wonder if he wants to feed the hatchlings or whether they pull at the worm in the attempt at making it smaller. At any rate, I am impressed as he does not eat the worm himself when he does not manage to give it to the female (even after several attempts).

Hatchling Support

8:01 am: Mom Blue Tit left the nest again and fed the 1st hatchling 2 more times in the last 20 minutes.She also pecked a bit at the cracked egg. But only a bit and then sat again on the eggs and hatchling.

8:05 am: The male Blue Tit called to the female. He flew to the entrance of the nesting box and gave her a worm. It was a bit big and he was pulling at it whilst she was taking it from her. She took it and then tried to reduce its size. She then ate it herself.

Blue Tits Hatch-ed/-ing!!!!

In NB-3 the eggs are hatching!!!!

This morning when I came in...(5 minutes ago ca. 7:30), I saw the first hatching (so tiny!!) and I noticed that a second egg was cracked!

I am so exicted!!!!

Mom Blue Tit left the nest once since I arrived to get a mini-worm to feed to the first hatchling. She had to call to it a couple of times before it opened it beak to be fed.

The temperatures are really low (about 6°C) and thus Mom Blue Tit continues brooding the unhatched eggs and warms up the 1st hatchling (which would otherwise die).

I will post as the others hatch!

Nest-Guarding rather than Brooding...

I guess I was wrong: in NB-1 and NB-4 brodding hast not begung yet.

The misleading factor: both females spend a significant amount of time in the nest. More than I had witnessed last year. I wonder if the territorial disputes play a role in this, what appears to me, over-proportionate "nesting" (i.e. just sitting around in the nest).

I have not recently witnessed any more disputes between the Sparrows and the new Great Tit pair. This however does not mean that the tension is not high.

What I am still wondering: are there any eggs at all in NB-1 and NB-4. When I look closely I see none in NB-4 (and of course I cannot see so deep inside the nest in NB-1).

I wonder if:
a) The Great Tit female is guarding an empty nest from (i) Sparrows or (ii) other Great Tits, or if
b) The Great Tit female is guarding the nest and lays eggs and hides them so well that it appears as though none are there


Interestingly enough, the male brings her food quite frequently. I wonder if the male is more aware than I am of what is going on or if he simply feeds the female because she is in the nest and will continue to do so until the hatchlings come. I cannot stop marvelling at the complexity of all of this wonderful process.

If I recall last year, nest building started on the 1st of May and the first egg was laid on the 4th. So if I compare, then theoretically it would not be too late if neither the Sparrow nor Great Tit have not laid eggs yet. However 2 things must not be forgotten:
1) Last year's winter seemed never to end and the temperatures were very low until end of April
2) The Blue Tit female in NB-3 is currently brooding 9 eggs...

I have started a statistics page/section as it seems as though it could be interesting to follow developments over the year and perhaps identify a trend if any.