Markus Varesvuo / Two male Black grouse (Tetrao / Lyrurus tetrix) fighting at lek. Utajarvi, Finland, April.

Ben Cranke / African fish eagle (Haliaeetus vocifer) pressurises a Saddle-billed stork (Ephippiorhynchus senegalensis) into dropping a freshly caught fish, so that it can be stolen for a meal. Liuwa Plain National...

Marie Read / Blue jays (Cyanocitta cristata) confrontation in snow, April 2020. New York State, USA.

Pal Hermansen / Brown bear (Ursus arctos), two showing aggression at night. Finland. August.

Carol Walker / Two wild pinto Mustang stallions battle for dominance in Sand Wash Basin, Colorado, USA.

Bence Mate / DUPLICATE Cuckoos (Cuculus canorus) squabbling, Kiskunsagi National Park, Pusztaszer, Hungary. February.

Bence Mate / Great egrets (Ardea alba) fighting with necks intertwined, Lake Csaj, Kiskunsagi National Park, Hungary. January.

Bence Mate / Montezuma oropendola (Psarocolius montezuma) two interacting, Costa Rica.

Bence Mate / Great egrets (Ardea alba) sky pointing, sizing each other up before fighting, Lake Csaj, Kiskunsagi National Park, Pusztaszer, Hungary. January.

Markus Varesvuo / Two male Black grouse (Tetrao / Lyrurus tetrix) fighting, Kuusamo, Finland, April.

Mark Bowler / Black capuchin, (Sapajus nigritus) female standing on hind legs, Rio de Janeiro, Brazil.

Andy Sands / German wasp (Vespula germanica) worker carrying rubbish, flying out of nest in air brick, Hertfordshire, England, UK. July

Erlend Haarberg / Arctic fox (Alopex lagopus) cubs looking curiously, Dovrefjell-Sunndalsfjella National Park, Norway, July.

Andy Rouse / Bengal tiger (Panthera tigris tigris) 11 month cub, Ranthambhore National Park, India.

Andy Rouse / Mountain hares (Lepus timidus) boxing in snow, Scotland, UK, December.

Nick Garbutt / Scarlet Ibis (Eudocimus ruber) flying into roost sight at dusk, Hato La Aurora Reserve, Los Llanos, Colombia, South America.

Ben Cranke / Steller's Sea Eagle (Haliaeetus pelagicus) portrait, Hokkaido, Japan. February.

Andy Rouse / Bengal Tiger (Panthera tigris tigris) female 'Noor T39' with cubs in water. Ranthambore National Park, India.

Bence Mate / Hooded crow (Corvus coronix) and Eurasian Magpie (Pica pica) waiting to scavenging White tailed eagle's (Haliaeetus albicilla) food, Pusztazer, Hungary.

Anup Shah / Lion (Panthera leo) cub aged about 2 years approaching with curiosity - remote wide angle perspective . Masai Mara National Reserve, Kenya. Taken with remote wide angle camera.

Edwin Giesbers / Female Jaguar (Panthera onca), captive, occurs in Southern and Central America.

Michele Westmorland / Booby (Sula nebouxii) looking at camera underwater, Galapagos Island.

Bert Willaert / Marbled poison dart frog (Epipedobates boulengeri) on leaf, Ecuador.

Fiona Rogers / Lion-tailed macaque (Macaca silenus) female portrait. Anamalai Tiger Reserve, Western Ghats, Tamil Nadu, India. Apr 2013.

Ingo Arndt / Grizzly bear (Ursus arctos horribilis) portrait, Lake Clark National Park, Alaska, USA, September.

Chris & Monique Fallows / African penguins (Spheniscus demersus) diving underwater, False Bay, Cape Town, South Africa.

Bruno DAmicis,Bruno D'Amicis / Wolf (Canis lupus) approaches a small herd of Red deer (Cervus elephas) in snow, Abruzzo, Italy. Highly commended in the Mammals category of the GDT Competition 2013

Bence Mate / Keel billed toucan (Ramphastos sulfuratus) in aggressive encounter with Montezuma Oropendola (Psarocolius montezuma) in rain, Laguna del Lagarto, Santa Rita, Costa Rica. Front cover bookplate of the H...

David Pattyn / Dalmatian Pelican (Pelecanus crispus) portrait, Lake Kerkini, Greece. February. Highly honoured in the Birds Category of Nature's Best Photography Windland Smith Rice International Awards Competition...

David Pattyn / Dalmatian Pelican (Pelecanus crispus) portrait, close-up of eyes, Lake Kerkini, Greece. February

Tony Phelps / Chacma baboon (Papio hamadryas ursinus) portrait of adult male. deHoop Nature reserve. Western Cape, South Africa.

Andy Rouse / African Lioness (Panthera leo) portrait, with aggressive expression because of cubs nearby Maasai Mara, Kenya, Africa

Alex Mustard / Portrait of a spotted sunfish (Lepomis punctatus) in front of reeds in a river. Rainbow River, Florida, United States of America.

Markus Varesvuo,Markus Varesvuo / Two male Black grouse (Lyrurus tetrix) displaying at lek, Kuusamo, Finland, April.

Anup Shah,Anup Shah / Male lion (Panthera leo) in confrontation with Cape buffalo (Syncerus caffer). Masai Mara National Reserve, Kenya, July

Anup Shah,Anup Shah / Male lion (Panthera leo) in confrontation with Cape buffalo (Syncerus caffer) Masai Mara National Reserve, Kenya

Andy Rouse / Indri (Indri indri) portrait in tropical rainforest habitat. Madagascar.

Danny Green / Two Red deer (Cervus elaphus) stags fighting, head to head, Bradgate Park, Leicestershire, UK. October.

Danny Green / Two Red deer (Cervus elaphus) stags fighting, head to head, Bradgate Park, Leicestershire, UK. October

Danny Green / Red deer (Cervus elaphus) stag chasing off another stag, Bradgate Park, Leicestershire, UK. October.

Danny Green / Two Red deer (Cervus elaphus) stags fighting, Bradgate Park, Leicestershire, UK. October.

Danny Green / Two Red deer (Cervus elaphus) stags fighting, Bradgate Park, Leicestershire, UK. October.

Danny Green / Two Red deer (Cervus elaphus) stags fighting, Bradgate Park, Leicestershire, UK. October

Nick Upton / Two pairs of Bewick's swans (Cygnus columbianus bewickii) calling and wing flapping in an aggressive encounter on flooded pastureland, Gloucestershire, UK. November.

Roland Seitre / Red fox (Vulpes vulpes) defending itself against a flock of Griffon vultures (Gyps fulvus), Catalonia, Spain.

Roland Seitre / Griffon vulture (Gyps fulvus) spreading its wings in a display of aggression at a defensive Red fox (Vulpes vulpes), Catalonia, Spain.

Staffan Widstrand / Black stork (Ciconia nigra) and Grey heron (Ardea cinerea) squabbling, Pusztaszer reserve, Hungary. May.