Sunday, 22 April 2012

Seaford/chiffchaff recordings (22/21 April 2012)

Sunday 22 April 2012.  Despite an uninspiring forecast Martyn Kenefick (just back from tour leading in Kuwait) and I decided to do a seawatch from Splash Point, Seaford.  We arrived at 06:30, shortly after John King, and all decided to brave the groyne rather than squeeze into a nearby shelter.  It was slow but we saw just enough to keep us hanging on until 10:30.  During that time we recorded the following heading east: 1 diver sp (probably not Red-throated), 76 Gannets, 49 Common Scoter (and 3 on the sea), 1 Great Skua, 4 Arctic Skuas (all dark phase), 7 Mediterranean Gulls (3 pairs and a first-summer), 3 Little Gulls (a bit distant but including a lovely adult), 32 Sandwich Terns, 6 Commic Terns and a particularly vicious hail storm.  The temperature was only 30 degrees centigrade less than MK is used to!
Splash Point, Seaford with hail storm approaching.  unfortunately no mega evident at the foot of the rainbow
North Thames Herring Gull SH5T was seen on a late visit to the Adur.  I'd seen it previously on 8 October 2011.  Also seen was an unreadable metal ringed Lesser Black-backed Gull.

North Thames Herring Gull SH5T
metal ringed Lesser Black-backed Gull.  A missed opportunity if it wasn't also colour-ringed

Saturday 21 April.  Having hopefully just about mastered the revamped blogger the following are recordings made of the Apuldram Chiffchaff that I was unable to add yesterday.  They were made with a Digital Voice Recorder through its inbuilt microphone .  I took two microphones with me but one had a dud AA battery and I had no spare while the other has an intermittent bad connection which chose to play up.  Despite this the recordings came out quite clearly although the only way I've been able to load them is by making a video of them playing.  The results sound a bit tinny.  I made 13 digital recordings in the 2.5 hours I was there.  4 are presented here along with two poor sound/vision quality videos of the bird singing.

Firstly the bird responded strongly to recordings of Iberian Chiffchaff, even when played quietly for comparative purposes.  It sounded similar to some of the recordings but generally seemed more variable in length and structure so that often one wasn't able to predict what was coming next.   This seems somewhat at variance with the recordings I've heard of Iberian Chiffchaffs from elsewhere but might be within the range of that species?

To me, I was most disappointed that I never heard it sing the typical 3x3 song "chiff chiff chiff tu tu tu weet weet weet" even when responding to such a recording from Spain.  Again this may well not be inconsistent with Iberian Chiffchaff but with hybirds, mixed singers and Chiffchaffs learning IC's song by proximity (and vice-versa) it is not something that I'm comfortable with without other compelling evidence.  Unfortunatly I did not hear the bird call which might have provided it as the thin call of IC is apparently distinctive.

Apuldram Chiffchaff recording 1: 21/04/12 @ 10:43 BST
Apuldram Chiffchaff recording 4: 21/04/12 @ 11:07 BST
Apuldram Chiffchaff recording 9: 21/04/12 @ 12:16 BST
Apuldram Chiffchaff recording 13: 21/04/12 @ 13:15 BST
Apuldram Chiffchaff: 21/04/12 @ 12:40 BST

                                            Apuldram Chiffchaff: 21/04/12 @ 12:13 BST

A few thoughts on the birds plumage, structure and behaviour.

Firstly I never saw the bird dip its tail in the manner frequently done by chiffchaffs.
Apuldram Chiffchaff looking encouragingly green above and almost slivery white on the belly but is this an effect of the light?  Note that although not black the legs appear uniformly dark, more so than one might like.
Apuldram Chiffchaff looking more ordinary?  Note the fairly solid ear coverts and uniform supercillium, features ore akin to Chiffchaff than Iberian?
The Advanced ID guide gives Iberian Chiffchaff's primary projection (past the longest tertial) as 70% or more than the length of the exposed tertials.  In Chiffchaff it is about 60%.  This photograph suggests the birds primary projection is a lot closer to 60% than 70%

Summary:  Voice.  This bird appears to be neither a typical Chiffchaff nor an Iberian Chiffchaff.   Despite its song at times being similar to some IC recordings, although to me is less structured and more 'all over place', its varied repertoire never included the 3x3 song I consider (based on very limited experience) to be typical, even when responding to such a song.  Neither did it manage more than a couple of notes of normal Chiffchaff.  Unfortunately it did not call.  Without knowing the range of variation within IC song I would not like to rule this bird out as an IC on voice but it was nowhere near as explosive or repetitive as I was expecting and left me feeling somewhat underwhelmed by it.

Behaviour.  The bird wasn't seen to dip its tail which is perhaps a point in favour of Iberian Chiffchaff.

Plumage.  Generally too Chiffchaff like, with a fairly uniform supercilium and solid ear coverts.  The plumage was not as right as one might hope, neither were the legs as pale.  Perhaps it falls within the range of variation but as for the voice it left me feeling somewhat underwhelmed.

Structure.  Perhaps most against this bird as an Iberian Chiffchaff is the short primary-projection apparent in the above image.

Conclusions.  It is not a typical bird but perhaps has too many anomalies to be considered a pure Iberian Chiffchaff.  While suggesting it is a hybrid might be seen as an easy option, it is one that might best fit in this case?  Hopefully we will get the opportunity to see a more distinctive individual in the county before too long.

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