King penguin (Aptenodytes patagonicus) adult and chick at breeding and nesting colony at Salisbury Plain, South Georgia, Polar Regions

Adult macaroni penguins (Eudyptes chrysolophus) plunging into the sea leaving their breeding colony at Elsehul on South Georgia, Southern Ocean, Polar Regions

Adult macaroni penguins (Eudyptes chrysolophus) plunging into the sea leaving their breeding colony at Elsehul on South Georgia, Southern Ocean, Polar Regions

Adult black-crowned night-heron (Nycticorax nycticorax falklandicus) on Carcass Island in the Falkland Islands, South America

Black-browed albatross (Thalassarche melanophrys) chick on the nest at nesting site on New Island, Falklands, South America

Hamerkop (Scopus umbretta) carrying nesting material, Zimanga Game Reserve, South Africa, Africa

Nesting Red-legged Cormorant (Poikilocarbo gaimardi) with chicks, Ballestas Islands, Paracas, Peru, South America

Gentoo penguin (Pygoscelis papua) adult with chicks at breeding colony on Damoy Point, Antarctica, Southern Ocean, Polar Regions

Great frigatebird (Fregata minor) chick in the nest in the Galapagos Island Archipelago, UNESCO World Heritage Site, Ecuador, South America

Adult blue-footed booby (Sula nebouxii) feeding chick in the Galapagos Island Archipelago, UNESCO World Heritage Site, Ecuador, South America

Gentoo penguin (Pygoscelis papua) mating behavior at Jougla Point on Wiencke Island, Antarctica, Southern Ocean, Polar Regions

King penguins (Aptenodytes patagonicus) in downy plumage (okum boys) on South Georgia Island, Polar Regions

Adult upland goose pair (Chloephaga picta) with goslings on Carcass Island in the Falkland Islands

Adult rockhopper penguin (Eudyptes chrysocome chrysocome) at breeding and molting colony on New Island, Falkland Islands

Adult Imperial Shag (Phalacrocorax (atriceps) atriceps) exhibiting intense breeding plumage, New Island, Falkland Islands

Adult dovekies (Little Auk) (Alle alle) at their breeding site amongst scree slopes at Rubini Rock, Tikhaya Bay, Hooker Island, Franz Josef Land, Russia, Arctic Ocean, Eurasia

Adult black-legged kittiwakes (Rissa tridactyla) feeding at the base of a glacier in the Svalbard Archipelago, Norway, Arctic, Europe

Adult black-legged kittiwakes (Rissa tridactyla) resting on ice in the Svalbard Archipelago, Barents Sea, Norway, Arctic, Europe

Brunnich's guillemot (Uria lomvia) breeding and nesting site at Cape Fanshawe in the Svalbard Archipelago, Norway, Arctic, Europe

Caspian Terns (Hydroprogne caspia) at breeding colony on Ile des Oiseaux in the Parc National du Delta du Saloum, UNESCO World Heritage Site, Senegal, West Africa, Africa

King penguin (Aptenodytes patagonicus) breeding and nesting colony at St. Andrews Bay on South Georgia, Southern Ocean, Polar Regions

Adelie penguin (Pygoscelis adeliae) adult defending chick against a skua on Torgersen Island, Antarctica, Polar Regions

Imperial Shags (Phalacrocorax (atriceps) atriceps) at breeding colony on small islets off the city of Ushuaia, Argentina, South America

Adult American oystercatcher (Haematopus palliatus galapagensis) feeding chick along the shoreline on Bartolome Island in the Galapagos Island Group, UNESCO World Heritage Site, Ecuador, South America

King penguin (Aptenodytes patagonicus) breeding and nesting colony on South Georgia Island, Southern Ocean, Polar Regions

Chinstrap penguin (Pygoscelis antarctica) breeding colony at Cooper Bay, South Georgia

Heermann's gulls (Larus heermanni), quarreling at breeding colony on Isla Rasa, Baja California, Sea of Cortez, Mexico, North Anerica

Couple of Great black-backed gulls in the cliffs of Etretat, Seine Maritime department, Normandy region, France, Europe

Nazca booby (Sula grantii) downy chick stretching its wings to gather strength for flight in the Galapagos Islands, UNESCO World Heritage Site, Ecuador, South America

King penguin (Aptenodytes patagonicus) adult and chick at breeding and nesting colony at Salisbury Plain, South Georgia, Polar Regions

Adult gentoo penguin (Pygoscelis papua) with minutes-old newly hatched chick at Gold Harbor on South Georgia

Adult gentoo penguin (Pygoscelis papua) feeding minutes-old newly hatched chick at Gold Harbor on South Georgia

Black-browed albatross (Thalassarche melanophrys) breeding colony on Steeple Jason Island in the Falkland Islands

Adult chinstrap penguin (Pygoscelis antarctica), at breeding colony at Half Moon Island, Antarctica, Polar Regions

Brunnich's guillemot (Uria lomvia) breeding and nesting site at Cape Fanshawe in the Svalbard Archipelago, Norway, Arctic, Europe

Magnificent frigatebird (Fregata magnificens), breeding colony in Bahia Gabriel, Isla del Espiritu Santo, Baja California Sur, Mexico, North America

Adult gentoo penguin (Pygoscelis papua) with minutes-old newly hatched chick at Gold Harbor on South Georgia

Heermann's gull (Larus heermanni), at breeding colony on Isla Rasa, Baja California, Sea of Cortez, Mexico, North Anerica

Adult elegant terns (Thalasseus elegans), at breeding colony on Isla Rasa, Baja California, Sea of Cortez, Mexico, North America

Heermann's gulls (Larus heermanni), at breeding colony on Isla Rasa, Baja California, Sea of Cortez, Mexico, North Anerica

Mallard duckling among daisies in meadow in The Cotswolds, Oxfordshire, England, United Kingdom

Female mallard duck and ducklings in stream in The Cotswolds, Oxfordshire, England, United Kingdom

Female mute swan building her nest, Donnington, Gloucestershire, United Kingdom

Female mute swan asleep on nest of moss and twigs, Donnington, Gloucestershire, The Cotswolds, England, United Kingdom

Avian pox outbreak at the king penguin (Aptenodytes patagonicus) breeding and nesting colony at Salisbury Plains, Bay of Isles on South Georgia Island, Southern Ocean.

Close-up portrait of a male willow ptarmigan (Lagopus lagopus) showing early breeding colors in its neck and eye combs, surveying its high-country territory in Southcentral Alaska's Chugach Mountains on an April day. The head and neck will become completely chocolate-brown as the bird's breeding colors develop, Alaska, United States of America

Male Common Ostrich (Struthio Camelus) In Breeding Plumage, Ngorongoro Crater, Tanzania