Tuesday, 27 September 2016

Barwits Revisited

Referring back to my March 2015 post - 'Which One's the Barwit?' - I thought that the current Autumnal prescence of up to 20 Barwits on the Axe estuary might be the right time to answer the questions which people have since posited regarding this 'issue'! As I said at the time, that blog post was simply to do with one Barwit in particular - the overwintering individual of Winter 2014-15. Thus, I didn't complicate that post by talking about Summer or Juvenile plumages. Today, I thought I'd deal with the Juvenile Blackwit scenario, as this seems to be the greatest cause of consternation and confusion; mainly because, in March 2015, there obviously weren't any juvenile birds about. The main difficulty seems to be that Black-tailed Godwits of juvenile age can often show a streaky mantle, as do all Bar-taileds. This, however, should not be a problem as juvenile Blackwits can easily be separated by their rusty-red neck and breast Autumn colouration which only occurs on Barwits in Spring females, and is lost by July.Even the male Barwit's extensive Spring red is lost by the time of its Southward migration, so it's extremely unlikely we'll get a reddish male on the Axe in the Autumn with anything like the strong red colour of a juvenile Blackwit. Also, the streaking on Barwits continues across the mantle, scapulars, wing-coverts and tertials which never happens in Blackwits. Even juvenile Blackwits have a very different pattern of spotting, not streaking, on the wing-coverts especially; I liken the patterning of Juv. Blackwit's wing-coverts to a 'Bar-of-Chocolate' as the spots often look like squares of chocolate arranged in a grid pattern, separated by pale criss-crossing lines. At various stages of immaturity a Blackwit's wing-coverts can also look quite plain or very finely spotted but never streaked like a Barwit's. Add to all of this the differences already discussed in March 2015, and you can't go wrong! Happy Birding, y'all!

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