Bernard Castelein / Darter ( Anhinga melanogaster) drying wings, Keoladeo NP, Bharatpur, India

Neil Aldridge / Portrait of an African darter (Anhinga rufa) on the Chobe River, Chobe National Park, Botswana.

Ann & Steve Toon / African darter (Anhinga rufa) with fish, Chobe river, Botswana.

Steven David Miller / Australasian darter (Anhinga novaehollandiae) female drying wings after fishing in Corroboree Billabong, Mary River, Northern Territory.

Bernard Castelein / Darter ( Anhinga melanogaster) drying wings, Keoladeo NP, Bharatpur, India

Bernard Castelein / Darter ( Anhinga melanogaster) drying wings, Keoladeo NP, Bharatpur, India

Robin Chittenden / Oriental darter (Anhinga melanogaster) submerged in water, Sri Lanka.

Guy Edwardes / African darter (Anhinga rufa) drying wings whilst perched in tree, Chobe River, Bostwana.

Guy Edwardes / African darter (Anhinga rufa) drying wings whilst perched on branch, Chobe River, Bostwana.

Eric Baccega / African darter (Anhinga rufa) drying its wings on mangrove tree. Baringo Lake. Kenya.

Eric Baccega / African darter (Anhinga rufa) drying its wings on mangrove tree. Baringo Lake. Kenya.

Yashpal Rathore / Oriental darter (Anhinga melanogaster), roosting at sunset, Keoladeo / Bharatpur National Park UNESCO Natural World Heritage Site, India

Ann & Steve Toon / African darter (Anhinga rufa), Chobe river, Botswana, June

Roger Powell / Oriental darter (Anhinga melanogaster) perched in small eucalyptus tree & drying water-logged plumage. Fogg Dam, Northern Territory, Australia

Roger Powell / Oriental darter (Anhinga melanogaster) perched in small eucalyptus tree. Fogg Dam, Northern Territory, Australia

Wim van den Heever / African darter (Anhinga rufa) drying its wings on a branch after hunting in the Chobe river, Botswana.

David Pattyn / Darters (Anhinga melanogaster) and Little cormorants (Phalacrocorax niger) sitting on a dead tree in a lake, Ranthambore National Park, Rajasthan, India

David Pattyn / Darters (Anhinga melanogaster) and Little cormorants (Phalacrocorax niger) sitting on a dead tree in a lake, Ranthambore National Park, Rajasthan, India

David Pattyn / Darters (Anhinga melanogaster) and Little cormorants (Phalacrocorax niger) sitting on a dead tree in a lake, Ranthambore National Park, Rajasthan, India

Bruno D'Amicis / African Darter (Anhinga rufa) nesting colony, Tana Mtsili Island, Lake Tana Biosphere Reserve, Ethiopia.

Bruno D'Amicis / African Darter (Anhinga rufa) in flight. Lake Tana Biosphere Reserve, Ethiopia.

Andy Rouse / Indian darter (Anhinga melanogaster) warming up wings, silhouetted at sunrise, Ranthambhore, India.

Juergen Freund / Australasian Darter (Anhinga novaehollandiae) with fish, Yellow Water wetlands, Northern Territory, Australia.

Enrique Lopez-Tapia / Anhinga (Anhinga rufa) in mangrove tree, Orango Island, Guinea-Bissau, December 2013.

Enrique Lopez-Tapia / Anhinga (Anhinga rufa) in mangrove tree, Orango Island, Guinea-Bissau, December 2013.

Loic Poidevin / African darter (Anhinga rufa) on a branch, Baringo Lake, Kenya, October.

Lou Coetzer / African darter (Anhinga rufa) drying wings, Chobe River, Botswana, June.

Lou Coetzer / African darter (Anhinga rufa) with fish stuck in its throat, Chobe River, Botswana, November.

Lou Coetzer / African darter (Anhinga rufa) choking on a fish, Chobe River, Botswana, November

Lou Coetzer / African darter (Anhinga rufa) in flight, Chobe River, Botswana, June.

Lou Coetzer / African darter (Anhinga rufa) in flight trying to retrieve dropped food, Chobe River, Botswana, October.

Lou Coetzer / African darter (Anhinga rufa) in flight low over water, Chobe River, Botswana, October.

Steven David Miller / Darter (Anhinga melanogaster) drying wings, Kakadu National Park, Northern Territory, Australia

Mike Potts / Indian Darter (Anhinga melanogaster) drying wings and preening feathers, Marlgu Billabong, near Wyndham, Western Australia, June

Rod Williams / Australian darter (Anhinga melanogaster novaehollandiae) head portrait, SE Queensland, Australia, March

Rod Williams / Australian Darter (Anhinga melanogaster novaehollandiae) head portrait, SE Queensland, Australia, March

Nick Garbutt / Silhouette of Oriental / Indian darter / Snake Bird (Anhinga melanogaster) basking to dry its wings. Kinabatangan River, Sabah, Borneo, Malaysia

Hanne & Jens Eriksen / Indian darter {Anhinga melanogaster} in tree drying wings, Tamil Nadu, India

Sharon Heald / Darter (Anhinga melanogaster) spreading wings on tree stump in lake, Chobe National Park, Botswana May 2008.

Bernard Castelein / Indian / Oriental darter (Anhinga melanogaster) perched on branch, Keoladeo Ghana / Bharatpur NP, Rajasthan, India

Nick Garbutt / Oriental / Indian darter {Anhinga melanogaster} drying wings, Bandhavgarh National Park, Madhya Pradesh, India.

Staffan Widstrand / Indian / Oriental darter drying wings {Anhinga melanogaster} Keoladeo Ghana NP, Bharatpur, Rajasthan, India

Bernard Castelein / Indian darter {Anhinga melanogaster} with neck extended, Keoladeo Ghana / Bharatpur NP, Rajasthan, India

Bernard Castelein / Indian darter {Anhinga melanogaster} preening, Keoladeo Ghana / Bharatpur NP, Rajasthan, India

Tony Heald / Indian darter drying wings {Anhinga melanogaster} Western Australia

Pete Oxford / RF - African darter (Anhinga rufa) perched on dead tree branch in river, basking, Murchison Falls National Park Uganda. (This image may be licensed either as rights managed or royalty free.)

Bernard Castelein / African darter (Anhinga rufa) standing on muddy riverbank with wings spread, drying its feathers after fishing, Allahein River, The Gambia.

Roland Seitre / Australian darter (Anhinga novaehollandiae) chick stretching its wings at nest with adult in background, Australia.

Bernard Castelein / Darter ( Anhinga melanogaster) drying wings, Keoladeo NP, Bharatpur, India

Bernard Castelein / African darter (Anhinga rufa) swimming in river, partially submerged, Bao Bolong Wetland Reserve, The Gambia.

Bernard Castelein / African darter (Anhinga rufa) perched in mangrove, Bao Bolong Wetland Reserve, The Gambia.

Bernard Castelein / African darter (Anhinga rufa) walking down muddy riverbank towards river, Bao Bolong Wetland Reserve, The Gambia.

Bernard Castelein / African darter (Anhinga rufa) swimming in river, Bao Bolong Wetland Reserve, The Gambia.

Doug Gimesy / Australasian darter (Anhinga novaehollandiae) male in flight. Middle Reedy Lake, Kerang, Victoria, Australia.

Doug Gimesy / Australasian darter (Anhinga novaehollandiae) male in flight. Middle Reedy Lake, Kerang, Victoria, Australia.

Doug Gimesy / Australasian darter (Anhinga novaehollandiae) male on nest. Middle Reedy Lake, Kerang, Victoria, Australia. November.

Guy Edwardes / African darter (Anhinga rufa) in flight over Chobe River. Chobe National Park, Botswana.

Guy Edwardes / African darter (Anhinga rufa) pair in courtship. Chobe River, Chobe National Park, Botswana.

Guy Edwardes / African darter (Anhinga rufa) pair in courtship, looking in same direction with open beaks. Chobe River, Chobe National Park, Botswana.

Guy Edwardes / African darter (Anhinga rufa) pair in courtship. Chobe River, Chobe National Park, Botswana.

Guy Edwardes / African darter (Anhinga rufa) drying wings, perched above water. Chobe River, Chobe National Park, Botswana.

Guy Edwardes / African darter (Anhinga rufa) drying wings, perched above water. Chobe River, Chobe National Park, Botswana.

Guy Edwardes / African darter (Anhinga rufa) drying wings, perched above water. Chobe River, Chobe National Park, Botswana.

Guy Edwardes / African darter (Anhinga rufa) drying wings, perched on tree snag. Chobe River, Chobe National Park, Botswana.

Bernard Castelein / African darter (Anhinga rufa) drying wings, perched on tree snag. Bao Bolong Wetland Reserve, Gambia.

Tony Heald / African darter (Anhinga rufa) Chobe National Park, Botswana.

Tim Laman / Darter (Anhinga melanogaster) male drying his wings after fishing. Cape York Peninsula, Queensland, Australia.

Sylvain Cordier / African darter (Anhinga rufa) drying plumage with wings spread, perched on tree. Lake Ziway, Rift Valley, Ethiopia.

Sylvain Cordier / African darter (Anhinga rufa) feeding chicks at nest. Lake Ziway, Rift Valley, Ethiopia.