Thank you, Graham, for your helpful comments. Our little bird was nowhere near as big as most of the Gulls, so that would seem to confirm it. But, not being birders, we do not carry binoculars so we have no idea what colours were on the bill.
And I am sorry that I misled you over the location by saying BWCP is 3 miles S of Aveley when it is 3 miles North of Aveley, but still about 7miles N of the Thames. It might have helped you if I had added 'inside the M25', but I did not realise that others might have no idea. I think you have been to BWCP on a fungus foray, but it was some years ago.
Your Forum
This forum has now been more or less replaced by the Club's Facebook page at 
The weblog below is for naturalists to use to report interesting sightings, ask questions, report on field meetings and generally post pictures and any information or questions generally relevant in some way to the wildlife and geology of Essex. You will need to register and be logged-on to post to the forum, and you need to upload pictures first, for use in posts. Find out more
The weblog below is for naturalists to use to report interesting sightings, ask questions, report on field meetings and generally post pictures and any information or questions generally relevant in some way to the wildlife and geology of Essex. You will need to register and be logged-on to post to the forum, and you need to upload pictures first, for use in posts. Find out more