Pink Footed Geese.

These birds are one of the reasons that I love autumn, they arrive here in their thousands just as the swallows and other summer migrants leave.
At present they are feeding on grain dropped in the stubble fields during the harvest. As the weather changes they move to other feeding grounds as well as the local wetlands and coast.
There are often huge flocks passing overhead in their familiar V-formation.
Their calls are very distinctive as they communicate whilst in flight.