A Mute Swan (Cygnus olor), in the marshes at Ham Wall National Nature Reserve, one of the Avalon Marshes nature reserves, near Glastonbury, Somerset, England, United Kingdom, Europe

Glastonbury Tor seen across the marshes of Ham Wall National Nature Reserve, one of the Avalon Marshes nature reserves, near Glastonbury, Somerset, England, United Kingdom, Europe

Marshes and reeds at Westhay Moor Nature Reserve, part of the Avalon Marshes, in the Somerset Levels, near Glastonbury, Somerset, England, United Kingdom, Europe

Evening sunlight view of Glastonbury Tor, seen across over Ham Wall Nature Reserve, one of the Avalon Marshes, near Glastonbury, Somerset, Great Britain.

Evening sunlight in spring over Ham Wall Nature Reserve, one of the Avalon Marshes, near Glastonbury, Somerset, Great Britain.

Dusk over the marshes of Ham Wall Nature Reserve, one of the Avalon Marshes, near Glastonbury, Somerset, Great Britain.

A wintery view of marshland, in Shapwick Heath Nature Reserve, one of the Avalon Marshes, near Glastonbury, Somerset, England, United Kingdom, Europe

A murmuration of starlings, numbering well over a million birds, flock together to roost at dusk on the Avalon Marshes at Shapwick Heath Nature Reserve in Somerset

A murmuration of starlings, numbering well over a million birds, form the shape of an atomic bomb mushroom cloud as they come in to roost at dusk on the Avalon Marshes at Shapwick Heath Nature Reserve in Somerset

Starlings, a murmuration of a million birds, in mushroom cloud shape as they drop to roost on Avalon Marshes, UK

Starlings, a murmuration of a million birds, in mushroom cloud shape as they drop to roost on Avalon Marshes, UK

Starlings, a murmuration of a million birds gather to roost above Avalon Marshes in Somerset, UK

Marsh grasses and reeds in the Avalon Marshes wetlands of the Somerset Levels near Shapwick Heath, Somerset, UK

A murmuration of starlings, numbering well over a million birds, gather as a flock to roost at dusk on the Avalon Marshes at Shapwick Heath Nature Reserve in Somerset

Starlings, a murmuration of a million birds gather to roost above Avalon Marshes in Somerset, UK

Avalon Marshes at Shapwick Heath Nature Reserve in Somerset, UK

Starlings, a murmuration of a million birds gather to roost on Avalon Marshes at Shapwick Heath Nature Reserve, UK

Marsh grasses and reeds in the Avalon Marshes wetlands of the Somerset Levels near Shapwick Heath, Somerset, UK

Avalon Marshes at Shapwick Heath Nature Reserve in Somerset, UK