Monday, 23 April 2018

Different from the Others 23rd April 2018


Personally, one of the joys of Spring in Oxfordshire and which I always eagerly look forward to is the arrival of migrant Yellow Wagtails at Farmoor Reservoir.

Invariably the first to arrive are the males, all bright and shining buttercup yellow on heads and underparts and with  greenish upperparts suffused with yellow, then add a natty black tail, bill and legs and they are an absolute picture and surely much under rated as one of our most strikingly colourful and vivacious native birds.


They are usually to be found by the edge of the tarmac perimeter track running above the grass bank that slopes down to the waterworks. Here there is a myriad of hatching flies and other insects to be gleaned from the track and bank, and they will often stand in the short green grass, still and uncertain  as I approach, their bright yellow heads and breasts all that is visible, confusing amongst the similarly yellow dandelion heads and swathes of purple blue ground ivy.


The Channel Wagtail with two Yellow Wagtails


Their numbers are declining but still, every year, double figures can be encountered, the birds scattered in a loose knit group along the perimeter track which they often share with Pied Wagtails and the occasional migrant White Wagtail. Sometimes they will fly a short distance to wander the concrete edges by the waters of the adjacent Farmoor One reservoir or fly with a cheery high pitched call to sit on the buildings and disused filter beds of the waterworks.



Male Yellow Wagtails
The majority are migrants passing through, stopping to take advantage of the abundance of flies to replenish energy reserves after their journey from winter homes in West Africa and before moving onwards to their breeding areas. April is always the peak month to see them at Farmoor and by mid May they are hard to find. I think the same individuals are not present throughout but that a continued passage of individual birds passes through over the period. Later the duller females are also often to be found joining the males.






For the last three years at least, the Yellow Wagtails have been joined by a rather beautiful hybrid male wagtail. Such a hybrid goes under the unofficial name of Channel Wagtail. Its parentage is the result of a pairing between Britain's subspecies of Yellow Wagtail Motacilla flava flavissima and a Blue Headed Wagtail Motacilla flava flava  which is to be found breeding as close as France and throughout western mainland Europe and western Russia. Both are considered to be a sub species of Yellow Wagtail and are part of a wider complex of sub species all encompassed under the catchall of one species, the Yellow Wagtail Motacilla flava.








Male 'Channel' Wagtail
Such hybrids can often catch out the unwary as they are not dissimilar to a true Blue Headed Wagtail but hybrid males at least can be told by the subtly paler colouration of the head and the fact that the yellow of the chin is replaced by white.

Let's forget the taxonomy for now and just enjoy the fortuitous combination that has brought about this lovely looking bird. It retains the bright yellow underparts and yellowish green upperparts of the normal Yellow Wagtail but its head, depending on the light is an exquisite shade of pale powder blue or grey with a prominent white supercilium, markedly different to the bright yellow heads of the Yellow Wagtails.





Channel Wagtails whilst scarce, are usually reported annually from Britain, involving one or two individuals from scattered locations. That one should have graced Farmoor for at least the last three years is remarkable and it could well be that a male, in a previous year, that was seen throughout the Spring and summer, formed a pair with a female Yellow Wagtail and bred nearby, so possibly the male here this year could be one of the progeny rather than the original male.

On any visit to Farmoor I always make a  point of seeking  out the Channel Wagtail amongst the Yellow Wagtails as it wanders through the grass seeking flies. Sometimes it is there and at other times I am disappointed, but that only leaves me with an increased desire to see it the next time.

2 comments:

  1. Looks like you got some better views this time! Such lovely birds!

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  2. I agree, very underated birds. In the 80s I was one of a group of Bradford birders pleased to find a male Blue-headed Wagtail paired with a Yellow on my patch. The male was immortalised by my annotated sketch being included in the local annual report. Years later I looked at the sketch. It was a very good description of ...
    a Channel Wagtail. It's not just old photos that leave us with egg on our faces Sometimes!

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