My current work is near the Thames, between London Bridge and Tower Bridge. For the most parts the only birds on the Thames are Feral Pigeons, Cormorants, Coots, LBB Gulls and Herring Gulls. Occasionally other birds appear, such as Grey Wagtail, and Mallards and Canada Goose flying up the river. Last week there was a distant falcon I am pretty sure was a Peregrine, and yesterday a pair of Terns, probably Common Terns, belted high up the river.
We get BHG's too. Normally passing by on their way somewhere. We haven't had any for a while until this week when a couple have been around. Post breeding presumably.