Some go, some come...

...and some remain with many questions unanswered....

The curious observer might have noticed that the young Tree Sparrows left the nest. To be exact they left at around 11 am on the 24th of May. The Blue Tits in NB-3 left between 7:30 and 11 am on the 26th of May.

After the Tree Sparrows left, I thought I should remove the nest (I had read something along the lines: remove the nest due to potential flees etc.) and so I removed it. On second thoughts, however decided to reinsert the nest. Considering effort which had gone into building it, I thought, that perhaps the sparrows would not want to build a second one. And so I reinserted the nest. I agree, it is not really a non-interference policy which I am following. It is difficult to decide what is best and given that observing them is already interference per se, given that building a house which removes natural reproduction areas and living in said house is also interference, I no longer know if it is at all non-hypocritical to say: observe is not interference but intervention is interference.

I am digressing.

At any rate I reinserted the nest and well today there have been visits. I have not yet been able to establish the nature of the visitor, but will be able to do so later.

Interestingly enough after the Tree Sparrows left, they were gone. Completely gone. I have not yet seen another Tree Sparrow since they left. I wonder where they are. I wonder if the parents led the young ones to feeding grounds in the fields, or in the woods, or near the river. I have no idea. The Great Tits last year could still be seen after 1 month of their leaving the nest. The differences between the species are intriguing!

I will be posting some videos of both the Tree Sparrows and Blue Tits in the next couple of days.

The Courage of Jumping into Emptiness

It is really funny to observe how the young birds prepare to depart. It is an amazing process.

One birdy hangs with half its body outside of the nesting box, the other half in the warmth of the box, waiting impatiently for an adult bird to come along and bring food. The desire to fly out is present but the missing courage to jump into emptiness is palpable. And thus the birdy waits for just one more round of feeding. Each time the excitement increases and the tiny feathered body slips just a couple millimeters further out of the box. In the meantime, in the back the excitement also grows as the remaining birdies unable to look out and be feed chirp incessently. Some test their wings other sinply hop about pushing whilst waiting in line for their turn at the entrance hole. The tension grows. The birdy slips one more time, a parent comes by bringing food taunting it to fly out. The birdy streches itself towards the parent. A few more millimeters of fragile birdy body hang out of the box, and then fear, it quickly pulls back.

The next birdy in line immediately hops foward and fills the hole but with only its head showing and it all starts over again millimeter by millimeter until the excitement is just too much to bare for just one young tiny birdy.

Pre-Departure Commotion?

18:59: I think the hatchling are almost ready to leave the nest.
I have the feeling that they are being invited by one (or both parents) to leave the warm and comfort of the nesting box. The parent bird flies to the entrance of the box and then flies away again. Sometimes it has a worm in its beak. The hatchlings are really active and are continously chirping. I wonder if the hatchlings will leave tonight or not. Last year the Great Tits left at 8 pm so it is not too late yet.

Sparrow Photos

It is now 21:16 and the hatchlings made their way by themselves back into the dome-protected nest. The mother Sparrow has not yet shown herself. Last night she slept near the nest but still within the nesting box. I wonder now whether something has happened to her or whether she now, given the size of the hatchlings, no longer sleeps in the nesting box (which is though suprising since there is enough space). In addition, I noticed, that the frequency with which the hathclings were fed this evening was quite low. I really hope nothings has happened.

Growing Fast

The four Sparrow hathclings are growing incredibly fast! In the last couple of days, the four occupy the outer spaces of the nest and no longer wait in the dome-protected nest area for the parents to arrive with food. In the semi-"live" stream it thus frequently happens that the image appears to be filled with a bird-body.

Yesterday, one hungry hatchling waiting...


and demanding...


Today, hatchling-traffic at nest entrance:



I image that they will be soon 2 weeks old. I hope they fly out when I am at home.

Four Very Hungry Tree Sparrow Hatchlings

Four starving hatchlings have wide open eyes and are starting to become very active....



Here is an image sequence and a video from one of the many times the hathclings were fed today.



The hatchlings are starting to have well defined feathers on their wings but still lack the fluffy plumage which will keep them warm once they leave the nest.

Eurasian Tree Sparrows: Interesting Wiki-Facts

According to Wikipedia: "The untidy nest is composed of hay, grass, wool or other material and lined with feathers, which improve the thermal insulation. A complete nest consists of three layers; base, lining and dome. The typical clutch is five or six eggs, white to pale grey and heavily marked with spots, small blotches, or speckling; they are 20 x 14 mm in size and weigh 2.1 g, of which 7% is shell. The eggs are incubated by both parents for 12–13 days before the altricial, naked chicks hatch, and a further 15–18 days elapse before they fledge. Two or three broods may be raised each year; birds breeding in colonies produce more eggs and fledglings from their first broods than solitary pairs, but the reverse is true for second and third clutches. Females which copulate frequently tend to lay more eggs and have a shorter incubation time, so within-pair mating may be an indicator of the pairs' reproductive ability. There is a significant level of promiscuity; in a Hungarian study, more than 9% of chicks were sired by extra-pair males, and 20% of the broods contained at least one extra-pair young."

In my opinion the nest is not untidy, actually. I can confirm the three layers though. I can also confirm that both parents incubated the eggs. 15-18 days is quite a short period (it is ca. 3 weeks, i.e. 18-21 days with Tit hathclings). I cannot say how many eggs there were. I wonder if there will be a second clutch.

I found a couple of papers on Eurasian Tree Sparrows, so I might have some more to report soon.



Here some interesting links:
http://blx1.bto.org/birdfacts/results/bob15980.htm
http://www.ibercajalav.net/img/421_TreeSparrowP.montanus.pdf
http://www.iucnredlist.org/apps/redlist/details/149116/0
http://ibc.lynxeds.com/species/eurasian-tree-sparrow-passer-montanus