Wild Wonders of Europe / Unterthiner / Whooper swans (Cygnus cygnus) Canada geese (Branta canadensis) and Greylag geese (Anser anser) in snow, Lake Tysslingen, Sweden, March 2009

Nick Upton / Bewick's swan (Cygnus columbiana bewickii) sliding on ice as it lands on a frozen marshland pool with other swans and Canada geese (Branta canadensis) in the background, Gloucestershire, UK, Febru...

Ernie Janes / Mute swan (Cygnus olor) attacking Canada goose (Branta canadensis) watched by Coots (Fulica atra) Fleet lagoon, Dorset, England, UK, June.

Staffan Widstrand / Wild Wonders of China / Group of Swan geese (Anser cygnoides) on grassland, Inner Mongolia, China

Staffan Widstrand / Wild Wonders of China / Swan geese (Anser cygnoides) flying, Inner Mongolia, China

Staffan Widstrand / Wild Wonders of China / Swan geese (Anser cygnoides) flying, Inner Mongolia, China

Staffan Widstrand / Wild Wonders of China / Group of Swan geese (Anser cygnoides) resting on ground, Inner Mongolia, China

Steve Downer / Femle Mute swan (Cygnus olor) swimming on a lake with cygnets on her back, Birmingham, England, UK, May.

Nick Upton / Pair of Greylag geese (Anser anser) walking and vocalising, with Shelduck (Tadorna tadorna) and a swimming Mute swan (Cygus olor) nearby, Gloucestershire, England, UK, January.

Nick Upton / A group of Greylag geese (Anser anser) walking past a mixed flock of swimming Wigeon (Anas penelope), resting Shelduck (Tadorna tadorna) and BewickÕs swans (Cygnus columbianus bewickii), Gloucestershi...

Nick Upton / Canada geese (Branta canadensis) grazing on flooded pasture in heavy rain, with Wigeon (Anas Penelope), Lapwings (Vanellus vanellus) and BewickÕs swans (Cygnus columbianus bewickii) foraging in the ba...

Nick Upton / Canada geese (Branta canadensis) preening on flooded pasture, with Golden plover (Pluvialis apricaria) landing in the background to join Shelduck (Tadorna tadorna), Mute swans (Cygnus olor), Wigeon (A...