October 13th, we observed and soundrecorded a grey-and-white 1st cy yellow wagtail s.l. in The Netherlands. The calls are remarkable and unlike anything we've ever heard in Europe, of yellow wagtails. After much browsing, surfing and reading, we think our bird might concern an eastern taxon, perhaps tschutschensis. The call is very explosive, rather high-pitched and short, with an almost Anthus-like character -it just does not sound right for anything in the WP.
I guess there must be quite a few people who have experience with aberrant and/or interesting yellow wagtails -please, take a sec. to check out the attached flight calls and the attached sonogram.
Hope you can help us!
Herman van Oosten