Male Red Grouse.
No interactions present.
Red grouse (the UK sub-species of willow ptarmigan), are all restricted to moorland and are the only UK grouse to be so - they are highly adapted to feeding on heather shoots, and to a lesser extent, willow and cotton grass.
The "eyebrows" are correctly called combs. They are erected and only visible to any significant extent when the bird is excited or stressed and especially so when they are territorial.
Combs is of course correct (thanks for that!).
There were several of these on the moorland up above the valley alongside a narrow road. Unsurprisingly, considering the time of year, most seemed to be in territorial pairs. A few lone males probably had mates hidden nearby.
Unpaired males are normal in red grouse/willow ptarmigan populations because of poorer survival of hens, but is especially so in UK red grouse populations where it is a complicated result of poor soils and over-grazing producing poor winter feeding. Especially given the weather this year, it is also probably a little too early for many hens to be sitting yet.
Lat/Lng: 57.2, -4.1
OS grid ref: NH7524