Hi Claire. It reminded me of a peacock as well but it seems unlikely as I was in a small area of woodland in South London -- it's also possible the sound was coming from someone's garden as I couldn't pinpoint the location. It's certainly a similar intonation but not sure "my" sound is quite as full-bodied and throaty as a peacock call...It crossed my mind that it was a fox but it doesn't seem to be a "typical" fox call either...although foxes apparently have a very wide vocabulary of calls so it could be?...To my ear it is very "bird-like"...Any ideas?
A Peacock for me as well.
My bird photos HERE
I agree, sounds like a Peacock; we had one in our garden a few years back and around April time it was occasionally calling like that in the lead up to finding a mate.
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Regards, Hazel
Did a bit of research and apparently there is one peacock in a nearby garden! Solved!