Can birds' nests be removed?
As a rule, no. Most birds are fully protected and you must allow the young to leave the nest before taking any action to block the entrance holes.
A general licence, issued by the government, allows ‘authorised persons’ to kill or take roof-nesting feral pigeons in Britain, and house sparrows, starlings and feral pigeons in Northern Ireland, and destroy their nests, but only if it can be shown that action was necessary for the purpose of preserving public health.
You should always avoid roofing work if you know birds are nesting there, but sometimes a roof nest is only discovered during renovation work. If this happens and the roof cannot be left until the young have flown, you can make an artificial nest box for a starling or sparrow quickly and simply by cutting a four-litre ice cream tub.
Cut an entrance close to the top of one long side (diameter 32 mm for house sparrow and 45 mm for starling), and roughen the surface below the entrance hole to give the birds some grip. On the opposite side, make two small holes about 25 mm (1 inch) down and 75 mm (3 inches) apart. Thread string through for fixing, and make two small drainage holes in the bottom. Place the nest together with eggs or young into the box. Close the box, leaving the side hole as the only entry.
Fix the box as near as possible to the original site. The parents will usually find their young and continue to look after them in the new location.