i was wondering if anyone knows why this happens.
my two bark at everything in the garden (as i have said before) and especially when the neighbours big dog starts so we had to fence off that part to stop them attacking each other through the fence.
4 doors up they have a young cavalier with quite a quiet yippy bark. it can bark for ages and my 2 just ignore it! very unusual for them.
i wondered if its because it sounds like a young or small dog? its not the distance because if a further away neighbours big dog starts they bark too
most odd

I watched a fascinating programme a little while ago and they were experimenting with dogs being able to tell the difference between different types of bark eg the "guarding/there's someone there who shouldn't be" bark, the "play with me" bark, the "I'm on my own and don't want to be" bark etc; and also different types of growls. I'm sure your dogs are just differentiating between the different types of bark and know that the "yippy" bark doesn't need to be worried about :)

Or it could just be because they are schnauzers - known to be vocal!

I too think it's the type of bark

Mine will alert bark at a specific trigger - usually something they think I ought to know about!  They can also be set off by a dog in the distance doing the same thing BUT all ignore the long duration YIP-pause-YIP-pause-YIP of our next door neighbours dog.  They obviously know she's just shouting for the sake of it and not at anything they feel the need to worry about.  They only join in if she is alert barking

Quite bright really aren't they :)