Nick Upton / Close up view of a Marbled white butterfly (Melanargia galathea) nectaring on a Field scabious (Knautia arvensis) flower, with another trying to court with it, Wiltshire, England, UK, July.

Nick Upton / Slow motion cllip of a Marbled white butterfly (Melanargia galathea) nectaring on a Creeping thistle (Cirsium arvense) flower, with another trying to court with it, Wiltshire, England, UK, July.

Bence Mate / Collared aracari (Pteroglossus torquatus) two perched, possibly courtship feeding, Costa Rica.

Bence Mate / Hoopoe (Upupa epops) courtship feeding, Pusztaszer, Hungary, May.

Bence Mate / Pair of European bee-eaters (Merops apiaster) with courtship offering of insect prey, Pusztaszer, Kiskunsagi National Park, Hungary

Roger Powell / European Bee-eater (Merops apiaster) courting a female by offering her a Small Copper butterfly (Lycaena phlaeas). Alentejo, Portugal, April.

Roger Powell / Black Guillemot {Cepphus grylle} with Sandeel fish in beak trying to entice a female to his nest site, Caithness, Scotland, UK

Wild Wonders of Europe / Widstra / Hoopoe (Upupa epops) male feeding female in courtship display, La Serena, Extremadura, Spain, April 2009

Wild Wonders of Europe / Nill / Red-backed shrike (Lanius collurio) pair, male feeding insect to female in courtship, Bulgaria, May 2008

Wild Wonders of Europe / Nill / Common roller (Coracias garrulus) female feeding on its courtship gift, Bulgaria, May 2008

Wild Wonders of Europe / Varesvuo / European Roller (Coracias garrulus) pair with courtship gift of insect prey, Pusztaszer, Hungary, May 2008

Dietmar Nill / Common roller courtship, male (on rightt) offers insect to female {Coracias garrulus}

Pedro Narra / Little Tern (Sterna albifrons) courtship feeding, Sado Estuary, Portugal. June

Hermann Brehm / Montagu's Harrier (Circus pygargus) prey transfer from male to female, Germany, July.

Philippe Clement / Teacher and school children watching a Red deer (Cervus elaphus) stag during the rut, Jaegersborg, Dyrehaven, Denmark, September.

David Tipling / Common linnet (Linaria cannabina) male feeding female near nest - courtship-feeding North Norfolk, England, UK. spring

Thomas Hinsche/ BIA / Eurasian Hoopoe (Upupa epops) male feeding female in courtship ritual, Saxony-Anhalt, Germany

Thomas Hinsche/ BIA / Eurasian Hoopoe (Upupa epops) male feeding female in courtship ritual, Saxony-Anhalt, Germany

Roger Powell / Arctic Tern (Sterna paradisaea) male courtship feeding female with a dragonfly nymph. Karigasniemi, Finnish Lapland, Finland, June.

Bruno D'Amicis / European Lanner falcon (Falco biarmicus feldeggi) prey exchange between adult male and larger female. Central Apennines, Italy, April.

Eric Medard / Female kestrel (Falco tunniculus) approaching male with lizard prey, Mayenne, France

Eric Medard / Female kestrel ( Falco tunniculus) approaching male with lizard prey, Mayenne, France

Eric Medard / Female kestrel (Falco tunniculus) taking lizard prey gift from male, Mayenne, France

Eric Medard / Female kestrel (Falco tunniculus) taking lizard prey gift from male, Mayenne, France

Sven Zacek / Ural owl (Strix uralensis) landing on branch to be fed by mate, Tartu County, Estonia. April Second Place in the Portfolio category of the Terre Sauvage Nature Images Awards 2017.

Sven Zacek / Ural owl (Strix uralensis) feeding mate, Tartu County, Estonia. April Highly commended in the Birds Category of the Terre Sauvage Nature Images Awards 2017. Second Place in the Portfolio category of t...

Tui De Roy / American flamingo (Phoenicopterus ruber) pair in courtship, group of three feeding, Punta Cormorant, Floreana Island, Galapagos

Edwin Giesbers / Greater flamingos (Phoenicopterus roseus) performing courtship display, Camargue, France, November.

Nick Upton / Male Great crested newt (Triturus crustatus) displaying to a female in a pond, with another female swimming past feeding on Water fleas (Daphnia pulex), Somerset, England, UK, February. Filmed at nig...

Philippe Clement / Red deer (Cervus elaphus) stag with two hinds during the rut in autumn, Jaegersborg Dyrehaven, Denmark, October.

Philippe Clement / Red deer (Cervus elaphus) stag displaying during the rut in autumn, Jaegersborg Dyrehaven, Denmark, October.

Philippe Clement / Red deer (Cervus elaphus) stag chasing white female through herd, Jaegersborg Dyrehaven, Denmark, October.

James Dunbar / Male Nursery web spider (Pisaura mirabilis) offering a nupital gift to a female, UK. Captive.

James Dunbar / Pair of Nursery web spiders (Pisaura mirabilis) feeding together, preparing to mate, UK. Captive.

Andy Rouse / Great crested grebe (Podiceps cristatus) trying to feed a large fish to a chick on mothers back, Cardiff, Wales, UK, March.

Andy Rouse / Great crested grebe (Podiceps cristatus) trying to feed a large fish to a chick on mothers back, Cardiff, Wales, UK, March.

James Dunbar / Male Garden spider (Araneus) courting a female, England, UK, September.

James Dunbar / Male Garden spider (Araneus) courting a female, England, UK, September.

James Dunbar / Male Garden spider (Araneus) courting a female by waving legs, England, UK, September.

James Dunbar / Male Garden spider (Araneus) courting a female, England, UK, September.

James Dunbar / Male Garden spider (Araneus) courting a female, England, UK, September.

James Dunbar / Male Garden spider (Araneus) courting a female, England, UK, September.

James Dunbar / Male Garden spider (Araneus) courting a female, England, UK, September.

James Dunbar / Close up of a male Garden spider (Araneus) courting a female, England, UK, September.

James Dunbar / Male Garden spider (Araneus) courting female by drumming on web strands, England, UK, September.

Nick Upton / Two pairs of Jackdaws (Corvus mondedula) vocalising and courting on the shore of a lake, with one holding a small food item as a courtship gift, Gloucestershire, England, UK, December.

Nick Upton / Gatekeeper butterfly (Pyronia tithonus) nectaring on Saw-wort flowers (Serratula tinctoria), with another butterfly courting it, Lower Woods Gloucestershire Wildlife Trust reserve, England, UK, July.

Hanne & Jens Eriksen / Great cormorant (Phalacrocorax carbo) pair bonding at nest, Germany, May.

Nick Upton / Pair of Shelduck (Tadorna tadorna) courting, with another pair dabbling nearby and another running past, Gloucestershire, England, UK, March.

Nick Upton / Small copper butterflies (Lycaena phlaeas) nectaring and courting on Wild marjoram flowers (Origanum vulgare), Wiltshire, England, UK, August.

Claudio Contreras / Socorro Parakeet (Aratinga holochlora brevipes) pair feeding each other, Socorro Island, Revillagigedo Archipelago Biosphere Reserve / Archipielago de Revillagigedo UNESCO Natural World Heritage Site...

Markus Varesvuo / Hoopoe (Upupa epops) male giving mating gift to female, Hungary May

Markus Varesvuo / Hoopoe (Upupa epops) male giving mating gift to female, Hungary May

Thomas Hinsche/ BIA / Eurasian Hoopoe (Upupa epops) male feeding female in courtship ritual, Saxony-Anhalt, Germany

Marie Read / Northern cardinal (Cardinalis cardinalis) male (right) feeding his mate in spring as part of courtship/pair formation, termed "allofeeding", New York, USA, May.

Marie Read / Northern cardinal (Cardinalis cardinalis) male (right) feeding his mate in spring as part of courtship/pair formation, termed "allofeeding", New York, USA, May.

Marie Read / Northern cardinal (Cardinalis cardinalis) male (right) feeding his mate in spring as part of courtship/pair formation, termed "allofeeding", New York, USA, May.

Andres M. Dominguez / Kingfisher (Alcedo athis) male offering female small crayfish prey, Sierra de Grazalema Natural Park, southern Spain, April.

Michel Poinsignon / Hoopoe (Upupa epops) male feeding female in courtship display, Pusztaszer, Hungary, April

Paul Hobson / European bee-eater (Merops apiaster) pair during courtship, male offering insect, Hungary, May.

Paul Hobson / European bee-eater (Merops apiaster) pair during courtship, male offering insect, Hungary, May.

Sven Zacek / Male Ural owl (Strix uralensis) courtship feeding the female in darkness, Southern Estonia, March.

Roger Powell / Collared pratincoles (Glareola pratincola) engaged in courtship display, male feeding female. Baragem do Caia, Santa eulalia, Elvas, Portugal, May.

Markus Varesvuo / Arctic Skua (Stercorarius parasiticus) adult male feeding adult female, Shetland, Scotland, UK, July

Loic Poidevin / Red-breasted parakeet (Psittacula alexandri) pair. Kaziranga National Park, Assam, India.

Ernie Janes / Black-headed gulls (Larus ridibundus) performing courtship display. Norfolk, UK, March.

Ernie Janes / Black-headed gulls (Larus ridibundus) performing courtship display. Norfolk, UK, March.

Markus Varesvuo / European Roller (Coracia garrulus) Male offering female insect prey in courtship, Hungary May

Dong Lei / Common Tern (Sterna hirundo) courtship feeding, Ruoergai National Nature Reserve, Sichuan Province, Qinghai-Tibet Plateau, China, Asia

Mike Wilkes / Grey headed kingfisher (Halcyon leucocephala) male passing insect to female, Lake Manyara, Tanzania.

Nick Upton / Female Marbled white butterfly (Melanargia galathea) feeding on a Creeping thistle flower (Cirsium arvense) in a chalk grassland meadow as a male hovers above to court her, Wiltshire, UK, July.

Roger Powell / Male dark phase Arctic Skua (Stercorarius parasiticus) courtship feeding light phase female. Varanger, Finmark, Norway, May.

Roger Powell / Territorial male Ruffs (Philomachus pugnax) fighting in display at their feeding grounds on the beach.Varanger, Finmark, Norway, May.

Roger Powell / Reeve or female Ruff (Philomachus pugnax) pretend feeding whilst studying a prostrate displaying satellite males at the lek. Varanger, Finmark, Norway, May.

Roger Powell / Male Little owl (Athene noctua) bringing food to a female perched on a fence post, Castro Verde, Alentejo, Portugal, April.

Roger Powell / Pair of Great spotted cuckoos (Clamator glandarius) mating, with the male offering the female a nupital gift, Castro Verde, Alentejo, Portugal.

Roger Powell / Pair of Great spotted cuckoos (Clamator glandarius) mating, with the male offering the female a nupital gift, Castro Verde, Alentejo, Portugal.

Cyril Ruoso / Common Raven (Corvus corax) courtship ritual female mimics fledgling and is fed by male suitor, Grands Causses, Cevennes National Park, France

Bence Mate / European roller (Coracias garrulus) feeding on insect prey, during courtship, Pusztaszer, Kiskunsagi National Park, Hungary

Danny Green / Arctic tern (Sterna paradisaea), adult in flight courtship feeding on ice shelf, Svalbard, July. Bookplate from Danny Green's 'The Long Journey North'

Andy Rouse / European hares (Lepus europaeus) male and female at start of courtship, UK, February

Roger Powell / European Bee-eater (Merops apiaster) courting a female by offering her a bee. Alentejo, Portugal, April.

Roger Powell / European Bee-eater (Merops apiaster) courting a female by offering it a bee, in front of flowers. Alentejo, Portugal, April.

Roger Powell / European Bee-eater (Merops apiaster) courting a female by offering it a bee. Alentejo, Portugal, April.

Andy Sands / Kingfisher (Alcedo atthis) male passing fish to female spring courtship behaviour, Hertfordshire, England, UK, March. Sequence 4 of 6.

Andy Sands / Kingfisher (Alcedo atthis) male passing fish to female during spring courtship behaviour, Hertfordshire, England, UK, March. Sequence 1 of 6.

Andy Sands / Kingfisher (Alcedo atthis) male passing fish to female early spring courtship behaviour, Hertfordshire, England, UK, March.

Jonathan Harrod / White-fronted Tern (Sterna striata) male presenting a fish as part of courtship display, Avon Heathcote Estuary, Christchurch, New Zealand

Jonathan Harrod / White-fronted Tern (Sterna striata) presenting a fish as part of courtship display, Avon Heathcote Estuary, Christchurch, New Zealand

Konrad Wothe / European Bee-eater (Merops apiaster) male feeding female during courtship, Bulgaria

David Welling / Cardinal (Cardinalis cardinalis) male and memale passing food between them, Rio Grande Valley, Texas, USA, June

Roger Powell / Ruff (Philomachus pugnax) male preening whilst resting on the edge of the feeding area, Varanger fjord, Arctic Norway. June

Michel Poinsignon / Common kingfisher (Alcedo atthis) male, on left, offering female, on right, a fish in courtship display, Lorraine, France, April

Nick Upton / Mating Dance Flies (Empis opaca) hanging from a grass stem, with female feeding on March fly courtship gift provided by male. Wiltshire pastureland, UK, May.

Nick Upton / Pair of Dance Flies (Empis opaca) mating, hanging from a grass stem, with female feeding on March Fly courtship gift provided by male. Wiltshire pastureland, UK, May.

Roger Powell / European Bee-eater (Merops apiaster) male flying in to present a Bee to his mate, Castro Verde, Portugal, April