Something Has Been Going On...

Yesterday, Friday the 12th, the Eurasian Tree Sparrow made a significant number of visits in the morning between 8 and 9 am, each time carrying twigs and such to the nest. Between 9 and 10 am, something odd happened, the bird flew into the nesting box, quickly landed and started singing incessantly. It was not its usual low frequency chirp with an inquisitive undertone...you can judge for yourself from the video below. From the flickering of the light from the entrance hole, it is clear that after some seconds of incessant chirping, another bird was perched at the outside of the nesting box and was looking inside. This second bird then leave and the sparrow in the box calms down. Its chirping slows and becomes inquisitive, or rather calling, again....well puzzling at any rate.

I wonder if one sparrow having done some work on the nest was attracting the attention of a potential partner to the nest or if the wild chirping can again be attributed to territorial disputes.

According to wikipedia, and I quote here: "Pairs may breed in isolation or in loose colonies, and will readily use nest boxes. In a Spanish study, boxes made from a mixture of wood and concrete (woodcrete) had a much higher occupancy rate than wooden boxes (76.5% versus 33.5%), and birds nesting in woodcrete sites had earlier clutches, a shorter incubation period and more breeding attempts per season. Clutch size and chick condition did not differ between nest box types, but reproductive success was higher in woodcrete, perhaps because the synthetic nests were 1.5 °C warmer than their wooden counterparts.

The male calls from near the nest site in spring to proclaim ownership and attract a mate. He may also carry nest material into the nest hole. The display and nest building is repeated in autumn. The preferred locations for the autumn display are old Eurasian Tree Sparrow nests, particularly those where nestlings had hatched. Empty nest boxes, and sites used by House Sparrows or other hole nesting birds, such as tits, Pied Flycatchers or Common Redstarts, are rarely used for the autumn display." (http://en.wikipedia.org/wiki/Eurasian_Tree_Sparrow)



Today, I noticed a Great Tit inspecting the nesting box (no bird species other than the sparrow visited the nesting box for 4 days). It was chirping wildly on the wooden fence on which the box hangs and was fluttering around as if on display.
I guess nothing is certain yet as to which species has claimed the nesting box its nesting ground.

Work in Progress...Nest Under Construction...At Last!

I am happy to announce that the Eurasian Tree Sparrow has begun making modifications to the nest. Today's visits were not limited to making space and moving feathers from one corner to the other of the nesting box, but additional material was carried into the nesting box. Twigs have now been added and these lie happily all over the place!

Additionally the visits were no longer limited to the 8-9 o'clock slot but continued on until ca. 11 o'clock, with however no additional visits in the afternoon as of 17:00 (last time I checked).

Eurasian Tree Sparrow - New Video

I tried generating a video again... it is better but has unfortunately no sound... but it is quite nice to see how it really examines the nests and does some serious work on making it comfortable.

This was yesterday's (Sunday 7th of March) early morning visit, ca. 8 o'clock.

If I have some spare time at some point, I would like to examine the frequencies at which each of the bird species sings, to see if there are any frequencies, or rather frequency distributions which are specific to any one species.... and yes I am a scientist, in case you have been wondering :-)

Early Morning Round

Of course I cannot be certain about my observations as I have only been observing successfully since March 2nd, i.e. just under a week. Some patterns have however come to my attention.

The most traffic has so far taken place in the morning. The Eurasian Tree Sparrow seems to have a liking for the 8-9 o'clock slot and multiple visits are made within the hour. Frequently two visits are in rapid succession during which the bird examines the nest, makes room, flattens the content, moves twigs and feathers, flies out of the hole only to perch again at the entrance, re-enter and repeat the above.

The Great Tit and Blue Tit come at more random hours, which might mean that multiple birds of these two species have visited the nest.

No visits have so far taken place during 12-14 o'clock. No visits have so far taken place after ca. 16 o'clock. Of course the days are still quite short (sunrise 06:53; sunset 18:14) and considering the bitter-cold weather, the birds will wait some more before they start laying eggs. After a week of temperatures above 0°C, they dropped again to below zero and a snow storm paid visit on Friday night and Saturday bringing 5-10 cm of fresh snow. According to the weather forecast the temperatures will remain below zero with only slight increases towards the end of this coming week but with more snow again next Saturday.

In the meantime I observe and wonder what they do, where they go, how they plan their rounds.

Territorial Disputes - Video

As promised a video of the territorial disputes between a Great Tit (in the second part of the short footage below) in the nesting box and an unknown bird outside perched near the entrance hole. The video is just a small portion of the 4.1 GB footage and I am afraid it does not do the happenings any justice. I will replace the video as soon as I get my hands onto decent video-cutting software.

Territorial Disputes

As already mentioned, there are three different bird species that have been visiting the nesting box. Although the Eurasian Tree Sparrow is the only one that is really working on the nest whilst the Blue and Great Tits just hang around, there have already been intense "verbal" disputes. Both the Blue and Great Tits have displayed aggressive behaviour towards other birds wanting to enter the nest, despite their apparent superficial interest in the box.

With the IR B/W camera I have recorded images of both the Blue and Great Tits sitting around in the box calmly and then suddenly becoming very loud and, for a bird that size, aggressive. At first I was not really sure about what was going on, until I realised that the ring of light coming from the entrance hole was flickering, meaning that another bird was perched next to the hole wanting to enter the box.

Yesterday, I managed to get excellent video footage of a Great Tit in the box "bickering" (I will have to read up on birds a bit to get my terms right, I hope you will excuse my "humanisation" of the birds 'til then) with the same flickering and with the chirping of another bird in the background but also quite loud.

I try not to side with any one bird, but I must confess, that I have taken a definite liking for the Eurasian Tree Sparrow, considering the work it has invested so far. I have read that due to the increasing use of land for agricultural purposes, and due to lack of food, Eurasian Tree Sparrows find it difficult to find nesting grounds and that their numbers are falling rapidly. Indeed this species has been added to the IUCN Red List of Threatened Species.



I will be loading a video of yesterday's territorial disputes later today...so stay tuned.

In flagranti

8:00 am: two Eurasian Tree Sparrows were feeding in the tree directly next to the nesting box. They then moved off to a branch closer to the box: one waiting whilst the other flew towards the box, landed, and disappeared inside.

The action continued on the monitor of my computer which is connected to the B/W IR camera...

I managed to take some pictures with my reflex camera...click on the picture!