David Woodfall / Black Grouse (Tetrao tetrix) male displaying at lek in snow, Ruabon Moor, Denbighshire, Wales, UK, April

David Woodfall / Black Grouse (Tetrao tetrix) male displaying at lek in snow, Ruabon Moor, Denbighshire, Wales, UK, April

David Kjaer / Grouse moor, Deeside, Scotland, April 2012.

David Kjaer / Grouse moor, Deeside, Scotland, April 2012.

Laurie Campbell / Lammermuir Hills heather moorland showing a patchwork of moorland managed for red grouse, Berwickshire, Scotland, August 2009

David Kjaer / Red Grouse (Lagopus lagopus) male perching on rocks on a moor. Scotland, UK, April.

Andy Sands / Merlin (Falco columbarius) female perched on Heather Grouse moor, Upper Teesdale, Co Durham, England, UK

Andy Sands / Merlin (Falco columbarius) male with bird prey perched on rock on Grouse moor, Upper Teesdale, Co Durham, England, UK

Andy Sands / Merlin (Falco columbarius) female flying low over Heather Grouse moor carrying bird prey, Upper Teesdale, Co Durham, England, UK

Laurie Campbell / Ling Heather (Calluna vulgaris) in flower on grouse moor, Lammermuir Hills, Berwickshire, Scotland, March

Andy Sands / Black Grouse / Black Cock / Moor Cock {Tetrao tetrix} displaying on Lek, Upper Teesdale, Co Durham, UK

Andy Sands / Black Grouse / Black Cock / Moor Cock {Tetrao tetrix} with moorland beyond, Upper Teesdale, Co Durham, England. UK

Andy Sands / Black Grouse / Black Cock / Moor Cock {Tetrao tetrix} displaying on Lek, Upper Teesdale, Co Durham, UK

Andy Sands / Black Grouse / Black Cock / Moor Cock {Tetrao tetrix} displaying on Lek, Upper Teesdale, Co Durham, UK

Jason Smalley / English short-haired, smooth, pointer working on a grouse moor, pointing at quarry bird during a shoot, UK

David Kjaer / Man beating ground during the burning of gorse/heather on the moor, Glen Shee, Scotland

David Kjaer / Man beating ground during the burning of gorse/heather on the moor, Glen Shee, Scotland

Staffan Widstrand / Male Black grouse {Tetrao tetrix} displaying, Vastmanland, Sweden.

Staffan Widstrand / Male Black grouse {Tetrao tetrix} displaying, Vastmanland, Sweden.

Staffan Widstrand / Male Black grouse {Tetrao tetrix} displaying, Vastmanland, Sweden.

Staffan Widstrand / Male Black grouse {Tetrao tetrix} displaying, Vastmanland, Sweden.

David Kjaer / Black grouse males (Tetrao tetrix) at lek. Deeside, Scotland, UK, Europe

David Kjaer / Black grouse males competing at lek on heather moor, Deeside, Scotland

David Kjaer / Black grouse males at lek on heather moor with Scots Pine, Scotland

David Kjaer / Black grouse males displaying at lek to attract females to mate (Tetrao tetrix) on heather moor with Scots Pine, Scotland

Patricio Robles Gil / Rock ptarmigan on moor {Lagopus mutus} Iceland

Pete Cairns / Line of guns in traditional butts on grouse shoot. Cairngorms NP, Scotland, UK

Pete Cairns / Line of beaters on grouse moor force birds into the air. Cairngorms NP, Scotland, UK

Brian Lightfoot / Common foxgloves {Digitalis purpurea} Scotland, UK Grouse moor

Brian Lightfoot / Common foxgloves {Digitalis purpurea} Scotland, UK Grouse moor

David Kjaer / Male red grouse on heather moor (Lagopus lagopus coticus) Scotland

Brian Lightfoot / Red grouse on heather moor, Scotland

Brian Lightfoot / Red grouse on heather moor, Scotland

Brian Lightfoot / Red grouseon heather moor, Scotland

Brian Lightfoot / Red grouse on heather moor, Scotland

David Woodfall / Black Grouse (Tetrao tetrix) male displaying at lek in snow, Ruabon Moor, Denbighshire, Wales, UK, April

David Woodfall / Black Grouse (Tetrao tetrix) male displaying at lek in snow, Ruabon Moor, Denbighshire, Wales, UK, April

David Woodfall / Black Grouse (Tetrao tetrix) male displaying at lek in snow, Ruabon Moor, Denbighshire, Wales, UK, April

David Woodfall / Black Grouse (Tetrao tetrix) male displaying at lek in snow, Ruabon Moor, Denbighshire, Wales, UK, April

David Woodfall / Black Grouse (Tetrao tetrix) males displaying at lek in snow, Ruabon Moor, Denbighshire, Wales, UK, April