Male black grouse (Lyrurus tetrix) fighting on snow covered field, Finland

Great-grey owl (Strix nebulosa) in flight, Finland

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

California gray whale calf (Eschrictius robustus), surfacing in San Ignacio Lagoon, Baja California, Mexico, North America

Southern elephant seal (Mirounga leonina) mating behavior on South Georgia Island, Southern Ocean

Magellanic penguin (Spheniscus magellanicus) at a breeding and molting site in Estancia San Lorenzo, Argentina

Magellanic penguin (Spheniscus magellanicus) at a breeding and molting site in Estancia San Lorenzo, Argentina

Sewell Mining Town, UNESCO World Heritage Site, Chile, South America

Adult sea otter (Enhydra lutris kenyoni) mother and pup in Inian Pass, Southeastern Alaska, United States of America

Adult humpback whale (Megaptera novaeangliae) tail throw among feeding whales in Southeast Alaska, United States of America

Adult black-browed albatross (Thalassarche melanophrys) in Elsehul on South Georgia, Southern Ocean, Polar Regions

Magdalena Island, Magallanes Region, Punta Arenas, Chile, South America

Northern giant petrels (Macronectes halli) fighting over the scavenging rights to a dead elephant seal pup at Royal Harbor, South Georgia

Northern giant petrels (Macronectes halli) fighting over the scavenging rights to a dead fur seal pup at St. Andrews Bay, South Georgia

Green sea turtle (Chelonia mydas), feeding on the sand near Caye Caulker, inside the Mesoamerican Barrier Reef, Belize

Adult humpback whale (Megaptera novaeangliae) tail throw among feeding whales in Southeast Alaska, United States of America

Two young polar bears (Ursus maritimus), feeding side-by-side on a fresh bearded seal kill on Spitsbergen, Svalbard, Norway

Adult bull southern elephant seals (Mirounga leonina) fighting for breeding grounds on South Georgia Island, Southern Ocean

Amy Cadge, staff member from the Lindblad Expedition ship National Geographic Explorer taking a photograph with a camera in the Svalbard Archipelago, Norway, Arctic, Europe

Adelie penguins on ice with dark skies, Antarctica, Polar Regions

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

Bottlenose dolphin (Tursiops truncatus), surfacing in Cabo Pulmo National Marine Park, Baja California Sur, Mexico,, North America