Bzzzzzzz

Three or four species of bumble bee in the backyard today (and a bee fly out the front). The Wood Warbler remains on territory too. Not one Bar-tailed Godwit flew over,... not one.

They're shiny, they excite

Gleamy-gleamy glinty-glinty, Adela reaumurella swarming in the back garden this evening, also a good few Common carder bees in amongst the swathes of Yellow Archangel and a good show of Bluebells. Wood Warbler singing within ear-shot of the backdoor too. It's just like Tom Bombadil's gaff here,... apart from the fact that some grubby little scrotes have set fire to the hillside just down the road.

Drat the file, and drat the bone!

Have spent the day carving a new leg for the captain from the jawbone of a Sperm Whale, very dusty affair, very dusty [sneezes]. Luckily there was no knee-joint to make, might have been tricky, just a mere replacement for a shin bone [sneezes]. Did stop briefly at lunchtime for a vomit, tomato and alfalfa sprout sandwich but then it was straight back into it.

Bumped into the Major on the train again this evening. We don't see eye to eye on a number of things but I don't think he understands. Me and the Major are from different worlds, I think that he's going quite insane, he goes along the pavement and comes back again, like he is on parade. Something like that anyhoo,... or was it just something I read,... or heard.

I'm really having trouble dreaming up new, ever more pointless, shite to put on here,...

Watch out! A picture of a bird...

More on the warbler

It can't be everyday that some poor Chiffchaff is misidentified as two different species between his breakfast and tea. The upshot of yesterday's shenanigans is that, should you feel the need, you can take a short stroll from the Newport Wetlands Reserve car park and take in a rather variation-laden Chiffchaff song; whether this is the result of the bird singing 'plastic'/'pre-crystallised' or just 'odd' [technical term] song, only time will tell. Today it was singing plenty of normal Chiffchaff, presumably much more so than yesterday, so my money is on the 'plastic'/'pre-crystallised' theory, and that the bird is currently going through the final stages of song development but, who knows, perhaps it was just being a shit yesterday and maliciously singing acoustic curve balls. Mind you, there is also the factoid that a little variation appears to have the ability to cause an awful lot of confusion, particularly when you chuck in the constructive/reconstructive nature of human memory, a lack of direct experience of a taxa and the apparently innate desire to pop things in a box marked "neat little box". Which reminds me,...

... the other odd phylloscopus inhabitants of the Wetlands Reserve, the mixed singing Willow Warblers (whose potential presence were definitely the source of yesterday afternoon's re-identification-misidentification). As far as I know, the bird which has spent the last few years near the bottom of Farmfield Lane hasn't been seen/heard yet this year (dead? late? gone elsewhere?) but the Goldcliff Pools car park individual is still on territory and in fine form. Joy.

Perry Lane Chiffchaff by darrylspittle

Two examples of the 'odd' phrase which, at times today, the bird performed repeatedly (although always moving on to more standard Chiffchaff song afterwards). Try and ignore the Whitethroat and the father talking to his nipper in the RaSPBerry playground in the background. The bird also performed a wide variation of 'tsilp'/'chiff' notes, at least four of which are disyllabic, a lot of Chiffchaffs have disyllabic 'tsilps' or 'tsalps' but maybe this one has more than most,... at the moment.

Goldcliff mixed singing Willow Warbler by darrylspittle

A few phrases from our mutual friend at the pools. Disregard the frankly dilatory delivery, it was almost lunchtime, the poor fella was probably as much in need of a coffee as I was by this stage; instead revel in his artful combination of his native sweet, scale-sliding cadence and the less mellifluous 'tsilps' and 'tsalps',... musical genius? Original composition? Or did he learn it off his dad down Farmfield Lane?

Oh no, I’ve died and gone to hell, and then I’ve fallen through a trapdoor and landed on a planet inhabited by either retarded or knowingly malicious phylloscopus warblers.

All quiet

Almost a complete lack of passage at Uskmouth today, just a few Grasshopper Warblers, one Lesser Whitethroat, one Wheatear and 15 Sand Martins overhead. The winter appears to have decimated (actually, worse than decimated) the Cetti's population, we appear to be down to 20-25% of recent peak numbers, just six recorded today.

A brief example of the levels of disturbance caused by the adjacent Uskmouth Power Station along the western boundary of this National Nature Reserve.

Cetti's Warbler and vehicle noise by darrylspittle

Of course, the Cetti's Warbler song and the noise from the vehicle occupy different frequency bands. Nothing of the Cetti's Warbler song dips below 1886 Hz and nothing of the vehicle noise reaches above 1448 Hz; if Cetti's Warblers have an effective built in high pass filter they may not give a toss, somehow though, I doubt this is the case. Just to prove the lack of overlap in 'acoustic space', the soundfile is split into three sections: 1. 'as heard', recording with no filtering beyond normalization to -1.0 dB; 2. 'Cetti's Warbler song', recording after application of a high pass filter with a cutoff frequency of 1800 Hz and a rolloff of 36 dB per octave; and 3. 'vehicle noise', recording after application of a low pass filter with a cutoff frequency of 1450 Hz and a rolloff of 36 dB per octave.

PS. Details of the machine making all the racket can be found here. Nice isn't it.
PPS. Hopefully, more on the warbler report tomorrow,... watch this cyberspace.

This week just gone

Whilst oscillating between Gloucestercestershire [the joke that will never tire] and South Wales I have been criss-crossing paths with: lots of Wheatear and Whitethroat, and smaller numbers of Little Ringed Plover, Green Sandpiper, Redstart, Reed Warbler and House Martin. Throughout, Swallows and Sand Martins passed by, sometimes at knee height into the breeze but mostly a tad higher up.

You can never have enough barb,... ask any farmer, gamekeeper, prison camp commandant, etc.

Lundy, ho!

A quick pitstop on Lundy. An overcast end to the previous night produced something approaching a proper fall. Hundreds of Willow Warblers plus Chiffchaffs and Blackcaps everywhere, hopping around on the shortest turf and everything. There must have been a rare there somewhere but we didn't find it. Had to make do with a female Pied Flycatcher feeding along a wall near the cemetery. Overhead a steady stream of Swallows and Sand Martins plus a single Tree Pipit.

PS. Two of the local House Sparrows were doing near-passable impressions of Yellow-browed Warblers,... 'fwee-eeest',... gawd knows?!

"Can't get the stink off, it's been hanging round for days"

The briefest glimpse into the abyss through which we have sailed,...

Three damned souls descend the rusted, encrusted ladder. Clamber aboard, hatch, and on down, backwards into the broiling bowels - sweat, fetid feet and fuel. Submarine walls ebb and flow, bunks pitch in the pitch, diesel crosses lung linings to course constricting veins, the bitter black veil descends. Shackled to the shapeless waters. Invisible tar black tentacles rise, reach down gagging gullets, wrench, acidic retch - uncontrollable convulsions, clear-biled oblivion.

[Hyperbole? What hyperbole?]

They're everywhere

Having noticed one or two reports on the GOS sightings page of mixed singing phylloscopus warblers, and not having the time/inclination to write anything original at the moment, I thought I'd post a slightly shortened version of my note that appeared in the Gwent Bird Report 2008 regarding the aforementioned confused songsters,...

Willow Warbler singing a mixed Willow Warbler/Chiffchaff song

On 26th April 2008, whilst at the Newport Wetland Reserve, I found a Willow Warbler on the Saltmarsh Grasslands singing mixed songs including both Willow Warbler and Chiffchaff syllables. Some songs appeared to be standard Willow Warbler, however, on occasions the bird would introduce a song with a varying number of 'tsilp tsalp' Chiffchaff syllables.

The only mixed singing I had heard before was a probable Willow Warbler near Blackbushe Airport, Hampshire, on 5th June 1997 which interspersed normal Willow Warbler song with soft 'trett trett' syllables performed in a typical Chiffchaff rhythm (as often heard from Chiffchaffs before or between their normal phrases). It was surprising then that, on 5th May 2008, whilst ringing at the Uskmouth Lagoons, I again noticed a Willow Warbler singing a combination of Willow Warbler and Chiffchaff song phrases. Several other observers saw and/or heard the bird (including Richard Clarke and Chris Jones), all agreed with the identification as Willow Warbler. This bird was present in an area of scrub alongside Reedbed 10 and was relocated at the same location on 10th May, at which point I recorded a short series of five songs including that shown in the sonogram below. The bird's song consisted of between one and three phrases, which became quieter as the song progressed. The first phrase began with two or three Willow Warbler-type introductory syllables, followed by between three and eight Chiffchaff-type syllables ('tsilp tsalp' notes, delivered at a slightly faster rate and higher frequency than in normal Chiffchaff) and then by five to ten syllables forming a Willow Warbler-type descending series. The second phrase, when present, was linked to the first by an intermediate, rising syllable and consisted of another Willow Warbler-type descending series of between four and seven syllables. Then followed either between two and nine Chiffchaff-type syllables or, when a third phrase was present, another intermediate, rising syllable and then a final three syllable Willow Warbler-type descending series.

The sonagram shows a representative song made up of a first phrase of three Willow Warbler-type introductory syllables (A), four Chiffchaff-type syllables (B) and a Willow Warbler-type descending series of nine syllables (C); this is then followed by a quieter second phrase (linked with a single syllable [D] rising in pitch and joining the final 'bottom' syllable of one descending series with the starting 'top' syllable of the next) consisting of another Willow Warbler-type descending series of eight syllables (E) followed by two Chiffchaff-type syllables (F).

On 1st June Craig Constance and David Hutton relocated the bird in the same area, noticed it was ringed, and managed to read the inscription (not a bad feat given each figure in the alphanumeric code is approximately 2 mm tall). The bird had initially been ringed at the site 18th June 2005 and had been retrapped on 30th April, 24th June and 8th July 2006, 29th April 2007 and on 5th May 2008. On each occasion biometrics and the basic wing formula had been noted confirming the identification of the bird as Willow Warbler. The presence of a cloacal protuberance, on all but one occasion, also confirmed the sex as, unsurprisingly, male. The combined sightings and ringing information suggests the bird held a territory throughout the breeding season in at least 2006 and 2008.

Mixed singing is widely, if uncommonly, reported in Willow Warbler and Chiffchaff (e.g. Fray 2007; Frost 1986; Norman 1985). The songs usually consist of Chiffchaff-type syllables followed by Willow Warbler song of varying length (Cramp 1992). Whilst natural hybridisation is known to occur between the two species (e.g. Asteling Strandberg 1998; McCarthy 2006) and hybrids have been reported singing mixed song (da Prato & da Prato 1986); mixed singers have usually been reported to be Willow Warblers (e.g. Lloyd 1926; Butlin 1940; Hopkins 2006). However, the behaviour has also been reported to occur in Chiffchaff (e.g. Wilson 1986) and the first genetically determined mixed singer was a Chiffchaff (Bensch et al. 2001). Hybridisation does not appear to explain the existence of most mixed singing birds, it is more likely that this behaviour is the result of anomalies in the song learning process.

References
Asteling, R. & Strandberg, A. (1998). Polygyny, hybridisation, double brooding, a case of site fidelity and time of laying of the Chiffchaff Phylloscopus collybita in southern Sweden. Ornis Svecica, 8: 125-128.
Bensch, S., Nilsson, L.G.R., Nothagen, P., Olsson, P. & Akesson, M. (2001). A Chiffchaff Phylloscopus c. collybita with mixed Chiffchaff and Willow Warbler Ph. trochilus song - genetic evidence. Ornis Svecica, 11: 108-111.
Butlin, S.M. (1940). Willow-Warbler with Chiffchaff-like notes in song. British Birds, 34: 65-66.
Cramp, S. (ed.) (1992). The Birds of the Western Palearctic Vol. VI. Oxford University Press, Oxford.
da Prato, S.R.D. & da Prato, E.S. (1986). Appearance and song of possible Chiffchaff x Willow Warbler hybrid. British Birds, 79: 341-342.
Fray, R. (2007). Mixed singing in Phylloscopus warblers. British Birds, 100: 307.
Frost, R.A. (1986). Phylloscopus warbler with songs of Chiffchaff and Willow Warbler. British Birds, 79: 340-341.
Hophins, G.R. (2006). Unusual song of Willow Warbler. British Birds, 99: 576-582.
Lloyd, B. (1926). Abnormal song of Willow Warbler. British Birds, 20: 153-154.
McCarthy E.M. (2006). Handbook of Avian Hybrids of the World. Oxford University Press, New York.
Norman, D. (1985). Possible hybrid Chiffchaff/Willow Warbler. Cheshire Bird Report, 1984: 89.
Wilson, C. (1986). Chiffchaff with songs of Chiffchaff and Willow Warbler. British Birds, 79: 342.

PS. The mixed singer reported from Goldcliff Pools on 28th March 2011 may well be a returning bird; there was a Willow Warbler near the car-parking area on 9th May 2010 whose song consisted of a Willow Warbler descending phrase followed by 'tsilp-tsilp-tsalp-tsilp...'
PPS. I have a sneaking suspician it isn't that rare at all.