How long has the buck been with the does? It might be possible they are just starting their breeding season and he is sensing it?
Our bucks have typically not started to breed until August/September. We're in KY though.
If you are home in the afternoons and mornings to check on them, then I would. That seems to be our bucks most active times.
If the does are starting to come in season, maybe he's starting to 'work on them.'
That's what our bucks have done. Especially the one we have now. He was working on them the day he got here lol We've had him almost 3 weeks. He's bred at least 3 of the 5, but possibly the other 2 however, we didn't see him breed them, but did see discharge from one of them.
usually it's just a little bit of white goo coming out of them. Sometimes it can make their tails messy. So if they had clean tails before breeding, and have some goo/dried goo on their tail now, could be he bred them.
Some bucks will make a fuss when a doe is in heat, and will chase her for a day or two. Some won't.
Ours typically do, and aren't real shy about it LOL
In fact, Saturday we had some family here, we were playing basketball in the backyard and on the other side of the fence the buck was breeding one of our does LOL
Some does will get very affectionate with the buck, and they will stay together/buck will follow her around.
Hopefully they give you a sign 'soon' so you can have a date for breeding & know when they are due.