Stakes and fishing line are an easy deterrent, bushes and shrubs are a more natural barrier as are bullrushes.
Keeping lawns at a minimum 3 inches tall also stops them from invading your property, they dont like to eat long grass, short, finely groomed lawn is more to their liking.
The Wildlife Management Group is contracted to service Bayshore common lands and waterways, not private property. They will service your property for a fee if you personally want to contact them.