Yellow Wagtails are a clear sign that spring is here. The diversity of subspecies going through N Iberia isn’t as large as in the Med coast, but a huge flock currently lingering at a coastal meadow site here in Asturies allowed detailed study and much fun. (Photo by Nacho Vega).

The default migrant ssp here are flava and flavissima, with some local iberiae in between. Brits and Europeans mix surprisingly well in these flocks, what inevitably originates intermediate populations, the so-called ‘Channel’ Wagtail. Here’s a male starring at mom & dad.

In the past, these birds were sometimes confused with Sykes’s Wagtail (M. f. beema), based on the pale blue head only. We now know they aren’t, but still catch our attention among migrant flocks. Sykes's taken in Kazakstan (Guillermo Rodríguez).

This particular flock also contained a good sample of the variation within nominate flava, from pretty dark-headed individuals to pale Channel-like birds. Further research is needed in order to find out whether this variability is geographical or just individual variation.

In addition, at least 2 birds showed both a whitish throat and nominate-like blue head (or even paler than average), a combination reminiscent of iberiae – flava intergrades. Does the presence in the flock of both these and Channel Wags suggest a SW origin?