- Lifespan
- 5–8 years in the wild
- Size & Weight
- 37–40 cm, wingspan 48–56 cm; 330–680 g
- Habitat
- Heather moorland and blanket bog at high altitude, typically above 300 m in Scotland and northern England.
- UK Distribution
- Year-round resident found exclusively in upland regions of Scotland, northern England (Pennines), and small populations in Wales. Does not migrate.
- Diet
- Almost entirely herbivorous, feeding on heather shoots, bilberry, crowberry, and other moorland plants; chicks eat insects initially but shift to vegetation.
- Predators
- Golden eagles, white-tailed eagles, hen harriers, short-eared owls, foxes, and stoats.
- Mating Season
- April to June
- Breeding
- Clutch size 6–9 eggs, incubation period 19–20 days, single brood per year. Chicks fledge at 12–14 days.
- Behaviour
- Highly territorial males establish and defend moorland territories with loud croaking calls ('go-back-go-back'). Social structure is based on loose flocks outside breeding season. Males and females both develop feathered legs and feet for insulation and snow-walking.