Get tough with pigeons that perch on your balcony, roof or windowsill. Forget scare tactics such as plastic windmills, noisemakers and cut-out cats, owls or hawks - they don't work with these urban pests.
Screen the birds out of wall recesses and window ledges with fine-mesh chicken wire sold at hardware and garden shops.
Sheets of plastic with plastic spikes at narrow intervals are available in hardware shops for use on flat roofs or window ledges. It is impossible for the pigeons to perch on them or find a comfortable foothold.
Run a strand of wire across a ledge at about half the height of a pigeon's breast. This will halve the amount of space the birds can use and will encourage them to move on.