or is it Colly birds?

Could be either really, colly is an old dialect word for black, so the black bird or calling bird can mean the same thing. Either way can you recognise a blackbird by its song? Below are my four calling birds, one of which is a blackbird, a coal-tit, a blue-tit and a bullfinch. Can you tell which is which? Answers at about the 20 second mark so be quick about your identification..

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