how does this second type look like?
It is long with a wingspan, chocolate-brown head (not black, although does look black from a distance), pale grey body, black tips to the primary wing feathers, and red bill and legs
Black-headed gull
This gull is long with a wingspan and weighs from 190-400 g (6.7-14.1 oz).

In flight, the white leading edge to the wing is a good field mark. The summer adult has a chocolate-brown head (not black, although does look black from a distance), pale grey body, black tips to the primary wing feathers, and red bill and legs. The hood is lost in winter, leaving just two dark spots.
where does the song london bridge is falling down come from Similar rhymes can be found across Europe, pre-dating the records in England; it is possible that the rhyme was acquired from one of these sources what is it all about? It deals with the depredations of London Bridge and attempts, realistic or fanciful, to repair it how did it originate? Similar rhymes can be found across Europe, "Knippelsbro Går Op og Ned" from Denmark, "Die Magdeburger Brück" from Germany, etc. It is possible that the rhyme was acquired from one of these sources what does it mean really? The meaning of the rhyme is not certain is there any game related to it? Yes, used in a children's singing game where is this aforesaid bridge located? Western end of the Pool of London what is this pool? It is a stretch of the River Thames from London Bridge to below Limehouse what is this river? It is a river that flows through southern England including London are there any wild animals near this? Various species of birds like cormorant, black-headed gull and herring gull
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Black-headed gull [SEP] Description
Like most gulls, it is highly gregarious in winter, both when feeding or in evening roosts. It is not a pelagic species and is rarely seen at sea far from coasts. The black-headed gull is a bold and opportunistic feeder. It eats insects, fish, seeds, worms, scraps, and carrion in towns, or invertebrates in ploughed fields with equal relish. It is a noisy species, especially in colonies, with a familiar "kree-ar" call. Its scientific name means "laughing gull".