I have no recording, but a bird has been calling for around an hour now in trees in our garden in Surrey (rural). A very strident and loud but mellow 'p-choo p-choo', every 0.5 seconds or so - relentless and insistent. I know most bird calls but this is new to me. A Song Thrush alatm call perhaps? Sorry to be so vague but has anyone any thoughts?
Obviously, without a recording we are in guessing territory based on your description. I think you can rule out Song Thrush which has more of a rattling alarm call.
The bird that springs to my mind is the persistent call of a Chaffinch which they can keep up for hours. There are a number of variations of this call but I found one which possibly matches most closely to your description
Play this audio clip
Anything like what you've been hearing?
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Tony
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Tony - thanks, but no. I'm familiar with the Chaffinch's 'pinking/tweeting' call. Mine is much more mellow. I will see if I can get a recording, but many thanks anyway.