Update: Freaky Great Tits (English)

For the last three months the strange calling Great Tits have been noticed in Germany. Time for an update!

Since the first one in Germany on 29th of September there have been 1361 records of 9759 individuals of strange calling Great Tits in Germany. As expected they turned up everywhere!

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Phenological occurrence of the Great Tits with the strange calls in Germany from 29th September 2012 to 20th February 2013, source: www.ornitho.de

In the German Big Garden Birdwatch 2013 27% more Great Tits have been counted than in January 2012; of course you have to keep in mind that this is not a scientific census (the data is taken by anybody who wants to take part). The invasion Great Tits surely have contributed to this.

On the Swiss ornitho.ch there have just been 91 records of 277 birds. But there hasn’t been a request for data as in Germany. My experiences are, that at least at the Swiss shores of Lake Constance they are as common as in southern Germany.

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Occurrence of the Strange Great Tits in Swiss from September 2012 to February 2013, source: ornitho.ch

In contrast to northern and central Germany the numbers of strange calling Great Tits in southern Germany haven’t changed. But they have changed their behaviour: call activity has become much lower so you have to wait quite a while for the call. Also the call seems to get used less often.

There was a conspicuous split in two groups in Decembre/January:

– single birds or pairs that keep territories and sing; I have never heard the call from these – probably the local Great Tits.

– flocks of up to 25 birds which were uttering the call all the time in autumn; now this call is used more random and seldom  -> in most flocks of Great Tits are „freaky“ ones at the moment (at least in southern Germany). The exact amount is hard to quantify but in flocks I had a closer look at 80-90% uttered the strange call.

Thanks to the article of Jochen Dierschke on birdingfrontiers a lot of birders from other european countries shared their observations. There have been records from Belgium, GB, Estonia, Finland, France, Luxembourg, the Netherlands, Austria, Poland and Switzerland. This call was new even to birders from north-eastern countries like Finland and Estonia!

On http://www.xeno-canto.org several recordings of the call have been uploaded, for example one from Dabrowka, Poland by Jarek Matusiak. This one even more recalls the recording of Albert Lastukhin at Cheboksary, east of Moscow. But it’s still 1kHz too low.

There is also one recording from the Netherlands from March 2009 that resembles the strange call. But it is not identical to the recent calls. Is it a variation of a freaky Great Tit (comparable to the plasticity of Red Crossbill calls that change a little over the years)? Or imitation of a bird that learned this call in eastern Europe? Or simply coincidence?

We have been wondering what the song of these birds would be like. Up to date there is no recording of a single bird, that utters the strange call and also sings. But as mentioned it is hard to find out because singing Great Tits don’t call a lot – and if they do, it’s not the strange one. Also, it is well known that the song of Great Tit is very variable. Therefore it is unlikely that the song is diagnostic.

The Tits will probably soon migrate back to their breeding grounds. So keep your eyes and ears open!

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