Can you legally shoot pidgeons, rabbits and squirrels on common land?
Common land does not mean that it is owned by the public, but it could be. There is always a landowner. Common land (to oversimplify) means that villagers have a right to graze their animals there, and certain other rights. Squirrels are vermin. Wild birds are protected. Rabbits can be taken by the landowner or person authorised by him or her. The occupier of the land can authorise only one person other than himself to take game on the land with a firearm. A game licence is required. The game laws are much more complicated than this, and it is worth reading a book on them.