Grouse and…American Mountain Ash??

Here’s something you like to see outside one of your grouse covers. Those are some plump looking birds. I think they’re feeding on Rowan, aka mountain ash berries. At first I thought it was Winterberry, but the berries are in clusters made me change my mind. Any botanists out there?

Ruffed Grouse Feeding on Mountain Ash?
Ruffed Grouse Feeding on Mountain Ash?
Winterberry in Maine
Mountain Ash?