Wednesday, 24 October 2012

Rarity boom!!

Yes, finally! Autumn has erupted and the birds are on the loose. Lucky me for spending so many hours on islands (Texel and Vlieland). I was so rather busy that I forgot to work on older recordings, let's say from couple of weeks ago..
At the second weekend from Deceptiontours (DT2), the young lads (including me) were cycling just past Leo Heemskerk (a little bit older lad ;) ) and only 50 meters farther, I discovered a Richard's pipit (Anthus richardi) on the ground. That's the way to make the difference! ;)
Some record-recording:

But last weekend it was booming. A few days before, a total of 4!! Olive-Backed Pipits were present on Vlieland near the water treatment plant. So I helped Jelmer with another recording, although it was not that good (lots of people..) so I just ran away.. Find my own bird, I said. Then in the afternoon, a phonecall.. Sjoerd had found a candidate Siberian Chiffchaff (Phylloscopus collybita tristis). As I have never heard the call of a Siberian Chiffchaff in real life, I was very curious! I listened to his recording (on his phone!) and I must say: I was convinced it was a 'tristis'. After searching some time, we found the bird, sometimes calling and sometimes showing, but it was very active. I recorded some calls.. But then.. I bumped my head in very interesting matter. 'abietinus' vs 'tristis', were to draw the border..

And the sonogram:

A 'sweeo' call. Known from both 'collybita' and 'abietinus' and might occur in 'tristis' however, no guarantees. On XC this type of call has been heard (and recorded) on birds that have the plumage of 'tristis' (for what we know!) in Oman and the type of call seems to become rarer towards India. This could imply a transition zone from 'abietinus' to 'tristis', or could imply that this sound is not (sub-)species specific! Another problem: Sjoerd's phone crashed, and he had the best recording, so hopefully the recording is saved on the SD.
Fortunately, in about a week I myself will visit Oman for fieldwork (watching Crab Plovers for 7 weeks) so I will be in the opportunity to sometimes record a Chiffchaff (and photograph it for the almost full documentation). (And yes, I already made a list of species where is only one or even no recording present in XC ;) ) Can, and hopefully will, do the same in Kazachstan next spring, will come back to that later.

So, bad luck.. Saturday was even worse! In short: was birdwatching with Mark, worked our asses of, checked EVERYTHING, found NOTHING, and then Radde's Warbler.. New species.. 4 hours of frustrating 'I see him! AAAAND it's gone' was taking me to the limit when I finally saw it. Criticaster me was discussing about the identification when Marijn called, I ignored his call.. 5 minutes later I gave Marijn a call and he was talking about 'something really strange, no idea what it was, some pipit with an metallic call in the forest (100 meter away!!!)'. We also went in to the forest and saw a crowd yelling and screaming and go mad whilst screaming 'It's a dendroica, it's a Myrtle Warbler'. What happened? The bird just was heard calling, 30 seconds ago.... F@#$ karma.. Gave a listen to the recording, thinking about Pechora and decided to play Pechora on my phone.. Surprised looks on the surrounding people asking: what is that? What are you playing? That's the sound!
Well yeah.. The sound really looks like Pechora Pipit (Anthus gustavi). However, only a few recordings are available and the sound does not match exactly. If it indeed was a pipit (bird was not seen through binoculars and only very short!), then it must have been a Pechora. The next day, the bird was heard 3 times more, but I didn't manage to hear it. However, to my opinion, there is not enough evidence.. But we will see!

In the evening I decided to stay on Vlieland to give the bird another chance. In the last daylight we were checking the fields near the village when we heard a 'raw rasping' wagtail. Alwin was the first one to spot it and yelled Citrine Wagtail. The others also saw the bird and the ID changed to Eastern Yellow Wagtail (Motacilla tschutschensis). It was windy, but fortunately, I made a recording in the hassle of tacking pics, clashing the ID, call others et cetera.. Only one call, but still! Damn what a sound. A rasping 'srieeuw' which is little bit reminding of Richard's Pipit. As we were photographing, a car approached us from behind, we gave him space to pass us, he got angry and horned loudly and flushed the birds to never see them again...
The recording (well.. ehm yeah..)

And the sonogram:

As you can see it is a bad recording. However, you do see the rasp in the call, the saw-tooth ('zaagtand' in Dutch, dunno if I can say it in English). It appears that the call is broken due to quality, yes it partly is, but it's due to the softer and harder quality of that part of the call, which is given its rasping sound (more or less). Untill now, this type of call has not been documented for Yellow Wagtails (Motacilla flava incl (sub)species). And the occurence always in late autumn and with very grey-white birds, this indicates an eastern origin. Here some pictures of the bird on
Well, another interesting matter: how do, for example, Yellow Wagtails from the subspecies 'beema' call? They are geographically close to M. tschutschensis.. Well, this spring I will go to Kazahkstan and as with the Siberian Chiffchaff, I hope to help with clinching the ID problems.

As if it couldn't get any stranger (note that the Eastern Yellow Wagtail was almost at the same spot as the Raddes and the Pechora), in the morning (in dense fog) we were waiting more or less at the Pechora spot, when all of a sudden (well, sort of) we were listening to an intriguing sound in the fog, which independently from each other drew our attention... Never seen the bird, nobody knows what it is.. A crate of beer for the one who knows (tip: do not only listen to the sound, also LOOK at it!). Note, it is the 'chep'-call

And the sonogram:

The feeling about the weekend changed when I got home and saw (again with help of Jelmer) that I recorded an Olive-Backed Pipit (Anthus hodgsoni) that flew over the village :)

Here some small extras. First a atmosphere sound on monday morning in the dense fog and immense migration!

And a comparison between the calls of Blackbird (Turdus merula) and Redwing (Turdus iliacus)

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