It's to do with the sheep not respecting dogs with too much white as the black colour is what shows the dominance over them. Doesn't mean they don't make excellent pets though!

The garden problem is that the people are just passing and when he barks they just carry on as if his barking is scaring them off, that's the way he'll see it. Everytime he barks the people go away and he has done his job.

Try to get people coming to the house and staying, fussing him and giving him treats so he see's people visiting as a good thing. Obviously he see's your home as his territory and as long as people aren't coming and staying he'll think his barking is warning them off.

We are inviting everyone and anyone over at the moment to get the pups used to people coming into the house. Luckily, socialisation is easy for us as we have people coming over with dogs all the time with the business.

Oh and Jayjay says thanks for the compliment!