Spring Birding: Opening to Flava & Channel Wagtail

Spring migration is now in full swing with all our summer migrants back in the UK and set for another breeding season. Everyone has a migrant which for them is the symbol of spring and for me it can only be one bird and that's the one and only Northern Wheatear, yet saying that there is one bird which each and every year never ceases to amaze me and a bird that I can't go a spring without seeing, so much so that I'd twitch one. That bird is one of the most iconic birds of the traditional British farmland and is the Western Yellow Wagtail aka Motacilla flava.

The RSPB estimate there are 15,000 territories in the UK but unfortunately it's on the decline as it is across it's global range. But that's not why were here, were here to give you a brief insight on one of the biggest and baddest avian subspecies complexes there is out there as well looking at one of common hybrids within the subspecies complex that frequently occurs on British soil.

As it currently stands 10 subspecies which make-up the Western Yellow Wagtail complex have been fully recognised by the International Ornithological Congress (IOC), which include the following:

  • M. f. flava - Blue-headed Wagtail - Western & Central Europe east to the Urals.
  • M. f. flavissima - Yellow-crowned Wagtail - Britain & English Channel coast line.
  • M. f. lutea - Yellow-headed Wagtail - Lower Volga to Irtysh River and Lake Zaysan
  • M. f. beema - Syke's Wagtail - North of lutea, east to Ladakh area
  • M. f. iberiae - Iberian Wagtail - SE France, Iberia & Maghreb.
  • M. f. cinereocapilla - Ashy-headed Wagtail - Sicily, Sardinia, Italy & Slovenia.
  • M. f. pygmaea - Egyptian Wagtail - Nile Delta
  • M. f. leucocephala - White-headed Wagtail -NW Mongolia & China boarder  
  • M. f. feldegg - Black-headed Wagtail - Balkans, Turkey, Iran & Afghanistan
  • M. f. thunbergi - Grey-headed Wagtail - Central & northern Scandinavia to NW Siberia.
For those who aren't aware then under IOC ruling M.f.fledegg includes race melanogrisea (Eastern Black-headed/Turkestan), with M.f.thunbergi including North Siberian race of plexa. The Western Yellow Wagtail complex is one of the, if not the most complicated avian masterpiece there is out there with still so much to be learnt with not every sub species being recognised every authority with some advocating as many 13 subspecies and some even splitting them as separate species.

Yellow-crowned Wagtail (Motacilla flava flavissima) - (Image by Allan Conlin, Lighthouse Birding)


In the UK out of 10 subspecies recognised by the IOU only 6 have been accepted onto the British list:
  • flavissima (Common/Breeder)
  •  flava (Uncommon/Has bred)
  • cinereocapilla (Rare/has bred)
  • thunbergi (Rare)
  •  feldegg (Rare < 25 records)
  •  iberia (MEGA)
M.f. beema (Syke's), was formerly on the British List until early 2010 when the BBRC rejected all 5 previously accepted records as they were either "unacceptable or inconclusive", it is believed by many that these so called "Skye's" were infact misidentified "Channel" Wagtails (flava X flavissima), or intergrades/hybrids of other flava subspecies. Lutea candidates have been found within the Europe however due to the lack of evidence and studying of them it's a hard one to nail unless your within there occurring range. Iberian Wagtail have had many candidates over the year but only 1 has been accepted by the BBRC.

Blue-headed Wagtail (M.f.flava) - A male with a somewhat very advocant white supercilium and throat (variation does occur as you can imagine), along with a somewhat steel blue would you say, cap. When it comes to identifying flava Wagtail's then adult/near adult males with their cap is the best and simplest at for an ID; however in some cases call is also needed.
(Image - Luke's Birding Blog)


Black-headed Wagtail (Motacilla flava feldegg) - Top image by Luke showing the consistent jet black that forms the cap. Thunbergi has a grey nape with blacker cheeks, another feature that I haven't yet learnt how to put on the blog yet is it's call which is a harsh "tsee-rr" which is best experienced in the field. (Image - Luke's Birding Blog)

As it is being cut off from the mainland Britain has it's very own subspecies of Western Yellow Wagtail which is Motacilla flava flavissima aka the Yellow-crowned Wagtail, with the nominate subspecies being Motacilla flava flava aka the Blue-headed Wagtail. Now as you can image there are areas of overlap within the subspecies populations (similar to that of White Wagtail), which as a result every so often you venture across the occasional hybrid with northern France being a melting pot for flava and flavissima hybrids, with a noticeable increase in flava and flavissima hybrids now popping up across the UK and breeding with flavissima.

Channel Wagtail (M.f.flava X M.f.Flavissima) - Best image I've ever come across of Channel Wagtail showing all of it's features in perfect clarity; the steel with a hint of blue cap and ear coverts along with those striking white Supercilium and throat. (Image - Nick Clayton)

Putative Dombrowskii Wagtail (M.f.flava X M.f.ledegg) - A bird that had a bit of Eastern Yellow Wagtail (Motacilla tschutschensis), on first thoughts, but after it was heard and compared to other hybrids an extreme variation in Dombrowskii couldn't be ruled out.  Photographed on Bardsey Island, Gwynedd, Wales on the 11th June 2012; (Image - BBFO Blog)


The result of flava & flavissima hybridisation is something called the "Channel Wagtail", a little easier on the mouth to pronounce compared to that of other hybrids such as that featured above, dombrowskii. Hybrids and intergrades do often cause problems with on occasion birds having to be left as Motacilla flava ssp due to a multitude of conflicting features. The same story applies to that of the "Channel Wagtail" with confusion between it and Blue-headed (flava) occurring more than you might expect. Being not the most experienced in the field with flava sp myself with only encountering flava, flavissima & iberiae the opportunity soon rose to catch sight of "Channel Wagtail" at Carr Lane Pools located on the outskirts of the glorious village of Hale, Cheshire, England. Being just 15mins on train (& 2hr's walking), thought a trip after college was in order as a reward for actually revising for exams

"Channel Wagtails" like that of all flava wagtails have variation, however the majority of males (female Channel are almost practically inseparable), are an easy target bird to pick out in a flock of flava/flavissima that I hope to explain with the following images and descriptions...

Channel Wagtail (M.f.flava X M.f.flavissima) - Adult male taken on a Canon 70D + 400mm lens at roughly 50m away, image is heavily cropped so quality isn't the best and low lighting (over cast with drizzle), wasn't helping. However the image clearly shows the birds much paler cap compared to that of a pure flava with Channel's, almost steel with a hint of blue. The image further shows the much bolder & extensive (compared to flava), white supercilium. (Image - Elliot's Birding Diaries)


Blue-headed Wagtail (M.f.flava) - Being taken in almost identical conditions to that of the Channel Wagtail, it allows for us too enable a comparison between the two birds despite the lack of quality: 1). Even at a distance the more extensive white on supercilium, throat & ear-coverts is much noticeable on the Channel than it is to that of the Blue-headed above which can only just be made out (variation in Blue-headed does occur with some having supercilium as bold as that of Channel!), 2). The main feature which is the grade of cap when it comes to separating the two and with both images taken in identical photographic conditions you can see the differences in grade. (Image - The Bird ID Company)

Channel Wagtail (M.f.flava X M.f.flavissima), Yellow-crowned Wagtail (M.f.Flavissima) and Pied Wagtail (M.a.yarrelli)

Channel Wagtail (M.f.flava X M.f.Flavissima) - Another award winning shot however in this particular image the grade of blue on the cap does appear to be remarkability dark and almost Blue-headed! As with any bird getting a series of images, not just 1 "good" image is vital/insurance if you like for getting as good of a identification as you can. In images 9 & 10 the cap appears to fit that perfectly of a Blue-headed, yet in image 6 (the same bird!), the cap is much much lighter, lighter infact than any pure flava even with variation could ever be. (Image - Elliot's Birding Diaries)

Channel Wagtail (M.f.flava X M.f.flavissima) & Yellow-crowned Wagtail (M.f.flavissima) - Best I could manage in terms of a comparison shot of the Channel & Yellow-crowned Wagtails. The bird pictured is very moble and being distant with plenty of places to hide isn't really what you want, but has thought to of paired up with a female flavissima so perhaps a later visits will provide better viewing and photographic opportunities for the bird as well of the 2nd generation of hybrid young. (Image -  Elliot's Birding Diaries


Well that's another post done and dusted and hope it's been a helpful insight into the Western Yellow Wagtail complex, as well as information which you could use yourself to find your very own Channel Wagtail. If there's one thing we all love about the natural world it's that you never stop learning the Western Yellow Wagtail is just one of many wild things we still have plenty to discover.

Thanks,
Elliot.


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