I saw this warbler this afternoon at the London Wetland Centre. I thought it might be a juvenile of some sort. The pale throat made me think of Reed Warbler, but it was flitting about bushes and on the ground. So I'm thinking maybe Willow Warbler (the legs look pale, so I reckon it's not a Chiffchaff). But having looked at a field guide I'm inclining to Garden Warbler. I am very confused! If anyone can ID it, I would be very grateful.
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