The slopes above Loch Muick may not be the first to feature in the thoughts of where to go for gully skiing in Scotland, but the nature of the terrain means that under certain conditions, they can provide some fun. With the tops of the runs around the 600-650m mark, these may be an option when conditions are too wild higher up the mountain, or you might take one of the lines in on return from either the Dubh Loch or Lochnagar. There are various aspects to choose from, depending upon snow conditions. Skiing above the loch is an enjoyable and memorable experience.
Approach
The most sensible location for access is the Spittal of Glenmuick. It is possible that when the slopes are good enough to ski, the access along the road could be problematic. A bike could be used to get to Glas-allt-Shiel, which is handy anyway for the Dubh Loch, for example, but if you want to get a few lines done in above the loch, I would just walk/skin to maintain flexibility.
Other options
The 2 obvious gully lines on the NW facing slope opposite the Glas-allt-Shiel are described here, but there are potentially a lot of shallow skiable gully lines. Several options are obvious on the east facing slope below An t-Sròn (710m), and along the slope above the land rover track to the Glas-allt-Shiel that could be taken in on a return from skiing on Lochnagar. Creag Bhiòrach on the south side of the loch also has a short steep gully splitting the craggy ground, along with some more mellow options each side of it.
Relevant Weather Forecasts