Thomas Hinsche/ BIA / Black-crowned Night Heron (Nycticorax nycticorax) juvenile foraging, Hungary

Thomas Hinsche/ BIA / Black-crowned Night Heron (Nycticorax nycticorax) juvenile, Hungary

Thomas Hinsche/ BIA / Black-crowned Night Heron (Nycticorax nycticorax) with fish prey, Hungary

Georg Scharf / Black-crowned Night Heron (Nycticorax nycticorax) foraging, Hungary

Konrad Wothe / Black-crowned Night Heron (Nycticorax nycticorax) calling, Europe

Shane P. White / Yellow-crowned Night Heron (Nyctanassa violacea) in defensive posture, Castara Beach, Trinidad and Tobago, Caribbean

Shane P. White / Yellow-crowned Night Heron (Nyctanassa violacea) in defensive posture, Castara Beach, Trinidad and Tobago, Caribbean

Tui De Roy / Yellow-crowned Night Heron (Nyctanassa violacea) parent with chicks in nest, Academy Bay, Santa Cruz Island, Galapagos Islands, Ecuador

Tui De Roy / Yellow-crowned Night Heron (Nyctanassa violacea) parent with chicks in nest, Academy Bay, Santa Cruz Island, Galapagos Islands, Ecuador

Thomas Hinsche/ BIA / Black-crowned Night Heron (Nycticorax nycticorax) feeding on fish prey, Hungary

Thomas Hinsche/ BIA / Black-crowned Night Heron (Nycticorax nycticorax) feeding on fish, Hungary

Thomas Hinsche/ BIA / Black-crowned Night Heron (Nycticorax nycticorax) scratching itself, Hungary

Thomas Hinsche/ BIA / Black-crowned Night Heron (Nycticorax nycticorax) foraging, Hungary

Ingo Arndt / Black-crowned Night Heron (Nycticorax nycticorax) carrying nesting material, Chengdu, China

Ingo Arndt / Black-crowned Night Heron (Nycticorax nycticorax) carrying nesting material, Chengdu, China

Sebastian Kennerknecht / Black-crowned Night Heron (Nycticorax nycticorax), Santa Cruz, Monterey Bay, California

Nate Chappell/ BIA / Yellow-crowned Night Heron (Nyctanassa violacea) swallowing frog, Texas

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) one week old chick with broken wing, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) one week old chick with broken wing, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) three week old chicks in carrier, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) one week old chicks in incubator, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) one week old chicks in incubator, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) fledgling crossing road, Ninth Street Rookery, Santa Rosa, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) fledgling with broken wing after being hit by car, Ninth Street Rookery, Santa Rosa, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) four week old chick begging for food, Sonoma County, California

Donald M. Jones / Black-crowned Night Heron (Nycticorax nycticorax), Montana

Donald M. Jones / Black-crowned Night Heron (Nycticorax nycticorax), Montana

Avi Meir / Black-crowned Night Heron (Nycticorax nycticorax) juvenile, Israel

Volker Hesse / Black-crowned Night Heron (Nycticorax nycticorax) juvenile, Florida

Markus Varesvuo / Night Heron (Nycticorax nycticorax) first summer adult, in flight, Hungary May 2007

Markus Varesvuo / Night Heron (Nycticorax nycticorax) in flight. Hungary. July 2006

Markus Varesvuo / Night Heron (Nycticorax nycticorax) in flight. Hungary. July 2006

Karl Seddon / Rufous Night-heron (Nycticorax caledonicus), Australia

Karl Seddon / Rufous Night-heron (Nycticorax caledonicus) juvenile, Australia

Alan Murphy / Yellow-crowned Night Heron (Nyctanassa violacea), Texas

Jan Wegener / Black-crowned Night Heron (Nycticorax nycticorax), Florida

David Pattyn / Night Heron (Nycticorax nycticorax) foraging in La Dombes lake area, France

Martin Willis / Rufous Night-heron (Nycticorax caledonicus) juvenile, Eyre Creek, Birdsville, Queensland, Australia

Sebastian Kennerknecht / Black-crowned Night Heron (Nycticorax nycticorax) juvenile in tidal marsh channel, Martin Luther King Jr. Regional Shoreline, California

Sebastian Kennerknecht / Black-crowned Night Heron (Nycticorax nycticorax) juvenile feeding, Martin Luther King Jr. Regional Shoreline, California

Gerrit Vyn / Yellow-crowned Night-Heron (Nyctanassa violacea) with fiddler crab prey. Plaquemines Parish, Louisiana, USA, July.

Gerrit Vyn / Yellow-crowned Night-Heron (Nyctanassa violacea) head portrait, Plaquemines Parish, Louisiana, USA. July.

Vincent Grafhorst / Black-crowned Night Heron (Nycticorax nycticorax) flying, Gaborone Game Reserve, Botswana

Pete Oxford / Black-crowned Night Heron (Nycticorax nycticorax) and chick in nest, Keppel Island, Falkland Islands

Pete Oxford / Black-crowned Night Heron (Nycticorax nycticorax), Keppel Island, Falkland Islands

Pete Oxford / Black-crowned Night Heron (Nycticorax nycticorax) and chicks in nest, Keppel Island, Falkland Islands

Wild Wonders of Europe / Varesvuo / Black crowned night heron (Nycticorax nycticorax) in flight, Pusztaszer, Hungary, May 2008

Scott Leslie / Black-crowned Night Heron (Nycticorax nycticorax), Everglades National Park, Florida

Scott Leslie / Black-crowned Night Heron (Nycticorax nycticorax), Everglades National Park, Florida

Scott Leslie / Black-crowned Night Heron (Nycticorax nycticorax) juvenile flying, Everglades National Park, Florida

Scott Leslie / Black-crowned Night Heron (Nycticorax nycticorax) flying, Everglades National Park, Florida

Kevin Schafer / Yellow-crowned Night-Heron (Nyctanassa violacea), Galapagos Islands, Ecuador

Jose B. Ruiz / Night heron (Nycticorax nycticorax) flock in flight, Donana National Park, Seville, Spain

Dietmar Nill / Night heron (Nycticorax nycticorax) in wetlands near the Danube River, Bulgaria

Pete Oxford / Yellow-crowned Night-Heron (Nyctanassa violacea) juvenile, Tower Island, Galapagos Islands, Ecuador

Theo Allofs / Rufous Night-Heron (Nycticorax caledonicus) portrait, Australia

Angelo Gandolfi / Night heron {Nyclicorax nyctycorax} beside waterfall, Italy

Flip de Nooyer / Black-crowned Night Heron (Nycticorax nycticorax) perching, Europe

Pete Oxford / Yellow-crowned Night-Heron (Nyctanassa violacea) perched in tree, Machalilla National Park, Ecuador

Konrad Wothe / Black-crowned Night Heron (Nycticorax nycticorax) with two fish in its beak, Greece

Tom Vezo / Yellow-crowned Night-Heron (Nyctanassa violacea) calling from perch, Texas

Tom Vezo / Yellow-crowned Night-Heron (Nyctanassa violacea) wading among Mangrove roots, Florida

Tom Vezo / Black-crowned Night Heron (Nycticorax nycticorax) chicks in nest, Isle of Meadows, New Jersey

Jim Brandenburg / Yellow-crowned Night-Heron (Nyctanassa violacea), Florida

Thomas Hinsche/ BIA / Black-crowned Night Heron (Nycticorax nycticorax) foraging, Hungary

Agustin Esmoris / Black-crowned Night Heron (Nycticorax nycticorax) calling, Peninsula Valdez, Argentina

Heike Odermatt / Black-crowned Night Heron (Nycticorax nycticorax) pair courting, Sea Lion Island, Falkland Islands

Tui De Roy / Yellow-crowned Night Heron (Nyctanassa violacea), Genovesa Island, Galapagos Islands, Ecuador

Tui De Roy / Yellow-crowned Night Heron (Nyctanassa violacea) and Sally Lightfoot Crab (Grapsus grapsus), Puerto Egas, Santiago Island, Galapagos Islands, Ecuador

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) juvenile, Sonoma County, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) dead chicks, which were rescued after being found in road but did not survive, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) being banded before release, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) caretaker, Isabel Luevano, casting wing of two week old chick, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) caretaker, Isabel Luevano, examining rescued chick, International Bird Rescue, Fairfield, California

Suzi Eszterhas / Black-crowned Night Heron (Nycticorax nycticorax) awaiting release, The Bird Rescue Center, Santa Rosa, California

Konrad Wothe / Yellow-crowned Night Heron (Nycticorax violaceus) flying, Tobago, West Indies, Caribbean

Donald M. Jones / Black-crowned Night Heron (Nycticorax nycticorax), Montana

Donald M. Jones / Black-crowned Night Heron (Nycticorax nycticorax) pair, Montana

Donald M. Jones / Black-crowned Night Heron (Nycticorax nycticorax), Florida

Cyril Ruoso / Black-crowned Night Heron (Nycticorax nycticorax) eating a bird chick of an unidentified species, Singapore

Steve Gettle / Yellow-crowned Night Heron (Nyctanassa violacea), J. N. Ding Darling National Wildlife Refuge, Florida

Julian Hume / Illustration of extinct water birds. Clockwise from top right: spectacled cormorant (Phalacrocorax perspicillatus) - extinct 1852,Bering Island; Reunion ibis (Threskiornis solitarius) - extinct 1710,R...

Pete Oxford / Black-crowned Night Heron (Nycticorax nycticorax) juvenile, Carcass Island, Falkland Islands

Pete Oxford / Black-crowned Night Heron (Nycticorax nycticorax) and chick in nest, Keppel Island, Falkland Islands

Pete Oxford / Black-crowned Night Heron (Nycticorax nycticorax), Keppel Island, Falkland Islands

Tim Fitzharris / Black-crowned Night Heron (Nycticorax nycticorax ), North America