Most likely they are bored out there and the barking has become self rewarding for them. You need to give them something that is more rewarding then barking.
Some dogs do great when put out in a yard to play- others cannot entertain themselves. Have you tried going out there and playing with them to keep them occupied? And then keeping them in the house when you can't be outside with them?
Also, now is a good time to teach the quiet command- this way at least if you are around you can tell them quiet and they will stop.
They shouldn't be allowed to bark for 45 minutes straight- besides being a nuisance to the neighbors it is reinforcing the behavior. The moment they start barking they need to be re-directed, if it is impossible, then they need to be brought inside.
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 Armani & Chloe |