We bicycled along the Thames Path from Erith to Woolwich and back again

Bird species seen (in no particular order): 

Black-Headed Gull
Lesser Black-Backed Gull

Herring Gull

Dunlin

Ringed Plover

Lapwing

Great Black-Backed Gull

Cormorant

Redshank

Carrion Crow

Mallard

Gadwall

Linnet 

House Sparrow

Moorhen

Teal

Shelduck

Magpie

Peregrine Falcon

Shoveller

Black-Tailed Godwit

Grey Heron

Common Snipe

Starling

Mute Swan

and Wood Pigeon

viz. twenty-seven species in total