Adult Swallow-tailed gull (Creagrus furcatus) in the Galapagos Island Archipelago, UNESCO World Heritage Site, Ecuador, South America

Adult bull Galapagos sea lion (Zalophus wollebaeki) posturing on Fernandina Island in the Galapagos Islands, UNESCO World Heritage Site, Ecuador, South America

Angry brown capuchin monkey (Cebus apella) (Sapajus apella) on tree, Tambopata National Reserve, Puerto Maldonado, Tambopata Province, Madre de Dios, Peru, South America

Chinstrap penguins (Pygoscelis antarctica), ecstatic display at breeding colony at Half Moon Island, Antarctica, Polar Regions

Battle-scarred beachmaster southern elephant seal (Mirounga leonina) bellowing a challenger, Peggotty Bluff, South Georgia, Polar Regions

Southern elephant seal (Mirounga leonina) bull issuing a vocalization challenge at Gold Harbour on South Georgia, Polar Regions

Adult bull southern elephant seal (Mirounga leonina) issuing a bellowing challenge at Gold Harbour on South Georgia, Polar Regions

Adult bull southern elephant seal (Mirounga leonina) issuing a bellowing challenge at Gold Harbour on South Georgia, Polar Regions

Adult bull southern elephant seal (Mirounga leonina) issuing a bellow towards another male, Gold Harbour, South Georgia, Polar Regions

Guadalupe fur seals (Arctocephalus townsendi), at new haul out on Las Animas Island, Baja California Sur, Sea of Cortez, Mexico, North America

Guadalupe fur seals (Arctocephalus townsendi), at new haul out on Las Animas Island, Baja California Sur, Sea of Cortez, Mexico, North America

King Penguin (Aptenodytes patagonicus) on the Falkland Islands in the South Atlantic. South America, Falkland Islands, January

Bull elk (Cervus canadensis) with misty breath in winter, Denver, Colorado, United States of America

Bull elk (Cervus canadensis) bugling in a field, Denver, Colorado, United States of America

Bull elk (Cervus canadensis) bugling, Denver, Colorado, United States of America