Ammonite / Cheetah (Acinonyx jubatus) cub suckling from mother, Masai Mara, Kenya.

Eric Medard / Male kestrel ( Falco tunniculus) with lizard prey for his mate, Mayenne, France

Eric Medard / Male kestrel (Falco tunniculus) with lizard prey for his mate, Mayenne, France

Eric Medard / Male Kestrel (Falco tunniculus) with lizard prey for his mate, Mayenne, France

Eric Medard / Kestrel ( Falco tunniculus) preening feathers, Mayenne, France

Eric Medard / Kestrel (Falco tunniculus) calling, Mayenne, France

Eric Medard / Female Kestrel ( Falco tunniculus) stretching, Mayenne, France

Eric Medard / Kestrels (Falco tunniculus) mating, Mayenne, France

Eric Medard / Kestrels (Falco tunniculus) mating, Mayenne, France

Eric Medard / Kestrels (Falco tunniculus) mating, Mayenne, France

Eric Medard / Kestrels (Falco tunniculus) about to mate, 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

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

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

Dong Lei / Common Kestrel (Falco tinnunculus) perched on branch, Balang Mountain, Wolong National Nature Reserve, Sichuan Giant Panda Sanctuaries - Wolong, Mt Siguniang and Jiajin Mountains UNESCO World Heritag...

Andres M. Dominguez / Female Kestrel (Falco tinnunculus) in flight, Donana Natural Park, Andalusia, Spain. January.

Loic Poidevin / Common kestrel (Falco tinnunculus) perched on post feeding on rodent prey, Marais Breton, Vendée, France, March.

Christophe Courteau / Male Common kestrel (Falco tinnunculus) preening, France, June.

SCOTLAND: The Big Picture / Female Common kestrel (Falco tinnunculus) perched on a branch, cleaning its beak and looking around, Scotland, UK, February.

Nick Upton / A male Kestrel (Falco tinnunculus) flying from its nest site under a rock overhang on a high sea cliff, Cornwall, England, UK, April.

Nick Upton / Slow motion clip of a male Kestrel (Falco tinnunculus) passing food to his mate at their nest site under a rock overhang on a high sea cliff, Cornwall, England, UK, April.

Dietmar Nill / Slow motion clip of a male Kestrel (Falco tinnunculus) hovering, Germany, May.

Juan Carlos Munoz / Lesser kestrel (Falco naumanni) on old roof, La Serena, Extemadura, Spain, April.

Terry Whittaker / Kestrel (Falco tinnunculus) on chalk cliffs, Kent, UK. July

Terry Whittaker / Kestrel (Falco tinnunculus) on chalk cliffs, Kent, UK. July

Terry Whittaker / Kestrel (Falco tinnunculus) on chalk cliffs, Kent, UK. July

SCOTLAND: The Big Picture / Kestrel (Falco tinnunculus) female perching on gate in snow, Scotland, UK, December.

SCOTLAND: The Big Picture / Kestrel (Falco tinnunculus) female perching on gate in snow, Scotland, UK, December.

SCOTLAND: The Big Picture / Kestrel (Falco tinnunculus) female perching on gate in falling snow, Scotland, UK, December.

SCOTLAND: The Big Picture / Kestrel (Falco tinnunculus) female perching on branch, Scotland, UK, January.

SCOTLAND: The Big Picture / Kestrel (Falco tinnunculus) female alighting onto perch , Scotland, UK.

Mark Hamblin / Kestrel (Falco tinnunculus) female taking flight from perch, Scotland, UK, February.

Christophe Courteau / Common kestrel (Falco tinnunculus) male with rodent to feed his chicks, Vendee, France, June

Christophe Courteau / Common kestrel (Falco tinnunculus) male with rodent to feed his chicks, Vendee, France, June

Graham Eaton / Kestrel (Falco tinnunculus) female standing on a branch of a fallen tree, overlooking farmland, Cheshire, UK February ( captive bird)

Hanne & Jens Eriksen / Common kestrel (Falco tinnunculus) female with prey, small bird, Oman, February

Hanne & Jens Eriksen / Common kestrel (Falco tinnunculus) female perched, Oman, November

SCOTLAND: The Big Picture / Kestrel (Falco tinnunculus) male flying, Cairngorms National Park, Scotland, UK, June.

Laurent Geslin / Kestrel (Falco tinnunculus) flying to nest box with prey, Strasbourg, France. June 2014.

Laurent Geslin / Kestrel (Falco tinnunculus) flying to nest box, blurred motion, Strasbourg, France.

Laurent Geslin / Kestrel (Falco tinnunculus) at nest box, Strasbourg, France, June.

Nick Garbutt / Lesser ketrel (Falco naumanni) in flight. Ndutu area, Ngorongoro Conservation Area NCA / Serengeti National Park, Tanzania.

Bernard Castelein / Common kestrel (Falco tinnunculus) in flight over rocks, Zeeland, the Netherlands, December

Bernard Castelein / Common kestrel (Falco tinnunculus) hunkered down in grass, Zeeland, the Netherlands, December

Bernard Castelein / Common kestrel (Falco tinnunculus) hunkered down in grass, Zeeland, the Netherlands, December

Martin Gabriel / Common kestrel (Falco tinnunculus) male, with captured mouse, Austria.

Nick Upton / Graham Guest at the top of a ladder checking a nestbox for Kestrel chicks (Falco tinnunculus) during a survey for the Hawk and Owl Trust's Kestrel Highways project, Congresbury, Somerset, UK, June. Mo...

Nick Upton / Adult Kestrel (Falco tinnunculus) found in a nestbox during a survey, Wiltshire, UK, June.

Nick Upton / Kestrel chick (Falco tinnunculus) having its developing primary feathers measured during a nestbox survey for the Hawk and Owl Trust's Kestrel Highways project, Congresbury, Somerset, UK, June. Model...

Nick Upton / Colin Morris weighing a Kestrel chick( Falco tinnunculus) in a bag during a nestbox survey for the the Hawk and Owl Trust's Kestrel Highways project, Congresbury, Somerset, UK, June. Model released.

Nick Upton / Four Kestrel chicks (Falco tinnunculus) in a nestbox, one with a mouse in its beak, found during a survey for the Hawk and Owl Trust's Kestrel Highways project, Congresbury, Somerset, UK, June.

Nick Upton / Colon Morris ringing a Kestrel chick (Falco tinnunculus) found during a nestbox survey for the the Hawk and Owl Trust's Kestrel Highways project, Congresbury, Somerset, UK, June. Model released.

Nick Upton / Kestrel chick (Falco tinnunculus) being ringed after being found during a nestbox survey for the the Hawk and Owl Trust's Kestrel Highways project, Congresbury, Somerset, UK, June. Model released.

Nick Upton / Kestrel chick (Falco tinnunculus) being ringed after being found during a nestbox survey for the the Hawk and Owl Trust's Kestrel Highways project, Congresbury, Somerset, UK, June. Model released.

Nick Upton / Graham Guest at the top of a ladder held by Barry Gray putting a Kestrel chick (Falco tinnunculus) back into a nestbox during a survey for the Hawk and Owl Trust's Kestrel Highways project, Congresbur...

Nick Upton / Graham Guest at the top of a ladder removing a Kestrel chick (Falco tinnunculus) from a nestbox for ringing and measuring during a survey for the Hawk and Owl Trust's Kestrel Highways project, Congres...

Nick Upton / Colin Morris takes a Kestrel chick (Falco tinnunculus) for ringing from a bag held by Keith Lapham as Barry Gray and Graham Guest look on during a nestbox survey for the the Hawk and Owl Trust's Kest...

Nick Upton / Kestrel chick (Falco tinnunculus) held after being ringed during a nestbox survey for the the Hawk and Owl Trust's Kestrel Highways project, Congresbury, Somerset, UK, June. Model released.

Nick Upton / Kestrel (Falco tinnunculus) and Barn owl (Tyto alba) nestboxes in a farm barn, Wiltshire, UK, June.

Pal Hermansen / Kestrel (Falco tinnunculus) perched on rock with heather, Rogaland, Norway, September.

Matthew Maran / Kestrel (Falco tinnunculus) female perched with people walking in the background. Hampstead Heath, London, England, UK, February.

Matthew Maran / Kestrel (Falco tinnunculus) perched, Hampstead Heath, London, England, UK, May.

Matthew Maran / Common kestrel (Falco tinnunculus) female perched on tree branch, next to can of cider, illustrating it's small size. Hampstead Heath, London, England, UK. June.

Matthew Maran / Kestrel (Falco tinnunculus) feeding on mouse, Hampstead Heath, England, UK. October.

Matthew Maran / Kestrel (Falco tinnunculus) male, Hampstead Heath, England, UK. October.

Matthew Maran / Kestrel (Falco tinnunculus) in flight against blue sky, Hampstead Heath, England, UK, October.

Matthew Maran / Kestrel (Falco tinnunculus) female hovering, Hampstead Heath, England, UK.

Matthew Maran / Kestrel (Falco tinnunculus) female feeding on a mouse, Hampstead Heath, England, UK. February.

Matthew Maran / Kestrel (Falco tinnunculus) female feeding on mouse, Hampstead Heath, England, UK. February.

Matthew Maran / Common kestrel (Falco tinnunculus) perched, with the Shard in the distance, Hampstead Heath, London, England, UK. June 2015.

Matthew Maran / Kestrel (Falco tinnunculus) in flight, rear view, Hampstead Heath, London, England, UK, August.

Matthew Maran / Common kestrel (Falco tinnunculus) female on ground, Hampstead Heath, London, England, UK, June.

Matthew Maran / Common kestrel (Falco tinnunculus) female in flight, Hampstead Heath, London, England, UK, June.

Matthew Maran / Common kestrel (Falco tinnunculus) female hunting over Cohen's fields Hampstead Heath, London, England, UK. June.

Matthew Maran / Kestrel (Falco tinnunculus) male, Hampstead Heath, England, UK.

Markus Varesvuo / Male Kestrel (Falco tinnunculus) flying, Spain, May.

Ernie Janes / Kestrel (Falco tinnunculus) male feeding young in nest, Norfolk, England, UK, July.

Roger Powell / Common kestrel (Falco tinnunculus) male on top of the nest-box with female inside, Monte da Aparica, Castro Verde, Alentejo, Portugal, May.

Roger Powell / Common kestrel (Falco tinnunculus) calling excitedly from the top of its nest box. Monte da Aparica, Castro Verde, Alentejo, Portugal, May.

Roger Powell / Common kestrel (Falco tinnunculus) male on top of the nest-box and looking down at the female emerging from the nest-box hole. Monte da Aparica, Castro Verde, Alentejo, Portugal, May.

Roger Powell / Common Kestrel (Falco tinnunculus) male arriving with a young House sparrow, about to pass it on to the female. Monte da Aparica, Castro Verde, Alentejo, Portugal, May.

Roger Powell / Common kestrel (Falco tinnunculus) female taking a young House sparrow to feed chicks with male calling, .Monte da Aparica, Castro Verde, Alentejo, Portugal

Roger Powell / Common kestrel (Falco tinnunculus) female taking a young House Sparrow from the beak of the male. Monte da Aparica, Castro Verde, Alentejo, Portugal

Roger Powell / Common kestrel (Falco tinnunculus) female calling to the male from the top of the nest box. Monte da Aparica, Castro Verde, Alentejo, Portugal, May.

Roger Powell / Common kestrel (Falco tinnunculus) female looking for her mate while standing on top of nest box. Monte da Aparica, Castro Verde, Alentejo, Portugal, May.

Roger Powell / Common kestrel (Falco tinnunculus) female and chick looking out of their nest box. Monte da Aparica, Castro Verde, Alentejo, Portugal, May.

Roger Powell / Common kestrel (Falco tinnunculus) cleaning its beak, perched on thatched roof, Texel Island, The Netherlands.

Roger Powell / Common kestrel (Falco tinnunculus) cleaning its beak, perched on thatched roof, Texel Island, The Netherlands.

Hanne & Jens Eriksen / Lesser kestrel (Falco naumanni) male perched, Oman, April.

Hanne & Jens Eriksen / Lesser kestrel (Falco naumanni) male in flight, Oman, April.

Loic Poidevin / Lesser kestrel (Falco naumanni) in flight, Saint Pons des Mauchiens, France, April

David Tipling / Lesser Kestrel (Falco naumanni) male at breeding colony, Spain spring

Matthew Maran / Kestrel (Falco tinnunculus) and Carrion crow (Corvus corone) in aerial battle. Hampstead Heath, London, UK, September.

Matthew Maran / Kestrel (Falco tinnunculus) and Carrion crow (Corvus corone) in aerial battle. Hampstead Heath, London, UK, September.

Ann & Steve Toon / Rock kestrel (Falco rupicolis) in a tree, Mountain Zebra National Park, Eastern Cape, South Africa, February