Peter Cairns / 2020VISION / Capercaillie (Tetrao urogallus) male displaying in pine forest in snow, Cairngorms NP, Highlands, Scotland, UK, January. Photographer quote: 'The capercaillie is Britain's fastest declining bird and r...

David Woodfall / Jamie Boyle RSPB warden for the Uists, putting out Black oat and Rye grass sileage for winter feed for declining Corn Buntings (Miliaria calandra) North Uist, Outer Hebrides, Scotland, UK, March.

David Woodfall / Jamie Boyle RSPB warden for the Uistsputting out Black oat and Rye grass sileage for winter feed for declining Corn Buntings (Miliaria calandra) North Uist, Outer Hebrides, Scotland, UK, March.

David Woodfall / Jamie Boyle RSPB Warden for the Uists putting out Black oat and Rye grass silage for winter feed for declining Corn Buntings (Miliaria calandra). North Uist, Outer Hebrides, Scotland, UK, March.

David Woodfall / Jamie Boyle, RSPB warden for the Uists putting out black oat and rye grass silage. Winter feed for declining corn buntings (Miliaria calandra), Balranald Nature Reserve, North Uist, Outer Hebrides, Sc...

David Woodfall / Jamie Boyle, RSPB warden for the Uists putting out black oat and rye grass silage. Winter feed for declining corn buntings (Miliaria calandra), Balranald Nature Reserve, North Uist, Outer Hebrides, Sc...

Ashley Cooper / Koala bear (Phascolarctos cinereus) Barmah Forest near Echuca, Victoria, Australia. February.

Ashley Cooper / Adelie penguins (Pygoscelis adeliae) with tourists walking past the colony, Madder Cliffs, Joinville Island, Antarctica.

Ashley Cooper / Guano in an Adelie Penguin (Pygoscelis adeliae) colony at Madder Cliffs, Joinville Island, Antarctica.

Nick Upton / Hoverfly (Xylota sylvarum) a woodland species declining in the UK, resting on a leaf in a garden, Wiltshire, UK, July.

Pete Cairns / Black grouse (Tetrao tetrix) female in lekking area, Deeside, Cairngorms NP, Scotland, April.

Andy Sands / Meadow Clary (Salvia pratensis), a rare and declining species in the UK. Hertfordshire, England, June.

Andy Sands / Corn Buttercup (Ranunculus arvensis) growing alongside Knotted Hedge-Parsley (Torilis nodosa) in corn field both are declining arable weeds. Bedfordshire, England, June.

Gerrit Vyn / Adult Ivory Gull (Pagophila eburnea). This arctic dependent species appears to be declining rapidly due to climate change. Resolute, Nunavut, Canada. June.

Gerrit Vyn / Adult Ivory Gull (Pagophila eburnea) resting on sea ice. This arctic dependent species appears to be declining rapidly due to climate change. Resolute, Nunavut, Canada. June.

Dave Watts / Brush-tailed Rock-Wallaby (Petogale penicillata) Declining and vulnerable, Victoria, Australia

Dave Watts / Brush-tailed Rock-Wallaby (Petrogale penicillata) Declining and vulnerable species, Victoria, Australia

Chris Mattison / Pollution lichen (Lecanora conizaeoides), a pollution indicating lichen formerly the most common lichen in industrialised areas, now declining, growing on a fence post, Derbyshire, UK. April.

Alex Hyde / Peppered moth (Biston betularia) showing a comparison of the melanistic form f. carbonaria next to the typical paler form. The melanistic form has long been cited by genetic studies as an example of i...

Alex Hyde / Peppered moth (Biston betularia) showing a comparison of the melanistic form f. carbonaria next to the typical paler form on dark soot-covered bark. The melanistic form has long been cited by genetic...

Alex Hyde / Peppered moth (Biston betularia) showing a comparison of the melanistic form f. carbonaria next to the typical paler form on dark soot-covered bark. The melanistic form has long been cited by genetic...

Alex Hyde / Peppered moth (Biston betularia) showing a comparison of the melanistic form f. carbonaria next to the typical paler form. The melanistic form has long been cited by genetic studies as an example of i...