Tomorrow I will be taking part in the BTO's (British Trust for Ornithology) BBS (Breeding Bird Survey). It is one of several BTO surveys that I participate in and basically involves surveying all the birds seen and heard in a randomly allocated 1km OS grid square. More information can be found here. And the BTO home page here.
The BTO is a superb organisation to get involved with and you can participate in as many, or as few, surveys as you like (you don't have to participate at all if you don't want to). I find that participating in organised scientific surveys really does take my bird watching to the next level and brings purpose to something that I enjoy. I would be out bird watching even without the BTO, so why not contribute to the conservation of all UK birds whilst I'm doing it?