Pea Moth.

Sugar snap and mangetout can escape pea moth caterpillars when they are eaten small. White maggots feed inside the pods so damage is  only spotted at harvest. Pea moths Cydia nigricana attack legumes including  garden peas, sweet peas and vetch.

Pea and bean weevil

Pea weevil Sitona lineatus eat the edges of leaves and cause havoc with seedlings. If necessary a bug spray may be effective

Pigeons can destroy a crop and if they are a problem netting is the answer.