The birds found in towns are, generally speaking, of the smaller varieties - sparrow, starling, thrush, blackbird, etc.

I got to thinking more about this after I had posted.
Send your average Londoner through one of the many public parks in the capital and, afterwards, ask him which birds he saw. He - or she - will name the varieties mentioned above, and possible blue-tits and wrens, if he knows that much. But he almost certainly won't include the large birds he saw - swans, geese, ducks. All of them are water-birds, and by "bird", I believe that said av. Londoner would only think of non-water birds.

Very strange. And am I right?