This is a little related to daisychain's post but with a sadder ending.
When i was kid growing up in north manchester the only birds i noticed were pigeons,'sparrers' and starlings and these tended to be all a murky brown with wheezy coughs because of the chimney smoke.I used to wonder [as kids do] what happened to birds when they die,because you never saw bird corpes ,other than pigeons squashed on the road. My dad said they flew to heaven, which seemed plausible to me at the time..
What prompted that distant memory was an unusual incident when i was driving through Northwich this morning [ your neck of the woods ,Ruth].I noticed a feral pigeon on a streetlamp a little distance ahead. Just as i approached it fell like a stone to the ground. Looking in my rear mirror[i could'nt stop because of the cars behind] it clearly was'nt moving.On my return journey [some half an hour later] it was still there and obviously an ex-pigeon.Presumably it died of natural causes no doubt brought on by the stress of eeking out a living on the mean streets of Northwich[unless hit by sniper from B & Q 's roof] --I wonder why we don't see more dead birds in urban areas given their numbers and relatively short life span,allowing for scavengers and street cleaners.Any thoughts ?