Winfried Wisniewski / White Stork (Ciconia ciconia) on nest, Extremadura, Spain

Jami Tarris / Caribou (Rangifer tarandus) entering teepee for food, Khovsgol, Mongolia

Martin Willis / Budgerigar (Melopsittacus undulatus) father with begging chick at nest cavity, Queensland, Australia

Michael Quinton / Northern Hawk Owl (Surnia ulula) pair at nest, Alaska

Michael Quinton / Northern Hawk Owl (Surnia ulula) peering from nest, Alaska

Michael Quinton / Northern Hawk Owl (Surnia ulula) parent with chicks at nest, Alaska

Graeme Guy/ BIA / Eastern Osprey (Pandion cristatus) parent feeding chick in nest, Western Australia, Australia

Tui De Roy / Blue-footed Booby (Sula nebouxii) parent and chicks at nest, Santa Cruz Island, Galapagos Islands, Ecuador

Tui De Roy / Blue-footed Booby (Sula nebouxii) incubating eggs, Santa Cruz Island, Galapagos Islands, Ecuador

Michael Quinton / Northern Flicker (Colaptes auratus) carrying fecal sac from nest cavity in forest, Alaska

Ingo Arndt / Purple Heron (Ardea purpurea) pair courting and building nest in reeds, Germany

Cyril Ruoso / Bonobo (Pan paniscus) young in day nest, Democratic Republic of the Congo