Yva Momatiuk & John Eastcott / Burchell's Zebra (Equus burchellii) herd Blue Wildebeest (Connochaetes taurinus) and Thomson's Gazelles (Eudorcas thomsonii) congregate near crossing, Mara River, Masai Mara National Reserve, Kenya

Yva Momatiuk & John Eastcott / Atlantic Puffin (Fratercula arctica) adults congregate in colony on coastal cliff during summer breeding season, Newfoundland, Canada

Steven Kazlowski / Polar bears (Ursus maritimus) with female and cub in background, congregate on newly formed pack ice where a Bowhead whale (Balaena mysticetus) carcass has been left by Inupiaq subsistence whalers, 10...

Colin Monteath / Shy Albatross (Thalassarche cauta) group congregate around fishing vessel, New Zealand

Sergey Gorshkov / Brown Bear (Ursus arctos) group foraging for salmon, normally solitary they may congregate at fishing rivers, Kamchatka, Russia

Jane Burton / Wood Ants (Formica rufa) congregate on top of nest mound in early spring. UK.

Sergey Gorshkov / Brown Bear (Ursus arctos) group foraging for salmon, normally solitary they may congregate at fishing rivers, Kamchatka, Russia

Yva Momatiuk & John Eastcott / Northern Fur Seal (Callorhinus ursinus) non-territorial bulls and sub-adult males congregate on haul out beach, St Paul Island, Pribilof Islands, Alaska