Steven David Miller / Sand bubble patterns created by Sand bubbler crabs (Scopimera inflata), Cape Hillsborough National Park, Queensland, Australia. September.

Sven Zacek / Ural owl (Strix uralensis) female feeding her young with part of a pellet it has regurgitated. Estonia, May.

Andy Sands / Filamentous fungus (Phycomyces blakesleeanus) beginning to form on mouse dropping. Hertfordshire, England, UK. November. Focus stacked image.

Guy Edwardes / Bateleur (Terathopius ecaudatus) pair perched on branch, one coughing up pellet. Savuti, Chobe National Park, Botswana.

David Perpinan / Kingfisher (Alcedo atthis) regurgitating a pellet, Barcelona, Spain, September.

Edwin Giesbers / Researchers examining Raptor pellets to identify eaten prey. Part of a 60 year long-term study led by Fred Koning to monitor raptors and their nests in a 3,400 hectare area of coastal dunes. Near Amst...

Edwin Giesbers / Raptor pellet in hand, researcher dissecting pellet to discover prey eaten by bird. Part of a 60 year long-term study led by Fred Koning to monitor raptors and their nests in a 3,400 hectare area of c...

John Chan / Juvenile female Hen harrier (Circus cyaneus) regurgitating a pellet as shorebirds fly by in foreground, Bolsa Chica Ecological Reserve, Southern California, USA, November.

Tony Wu / Juvenile Chinese pond turtle (Mauremys reevesii), taking food from hand. A tiny food pellet is visible at the tip of the finger. Rescued from a road, hand-reared now, Japan.

John Chan / Great horned owl (Bubo virginianus) regurgitating a pellet, Bolsa Chica Ecological Reserve, Southern California, USA, September.

John Chan / Great horned owl (Bubo virginianus) regurgitating a pellet, Bolsa Chica Ecological Reserve, Southern California, USA, September.

Markus Varesvuo / Sparrowhawk (Accipiter nisus) juvenile trying to vomit a pellet Norway, October.

John Chan / Great horned owl (Bubo virginianus) chick coughing up a pellet, Southern California, USA, June.

Suzi Eszterhas / Brandt's Cormorant (Phalacrocorax penicillatus) pellet of worms coughed up by cormorant International Bird Rescue, Fairfield, California

Eric Medard / Sparrowhawk (Accipter nisus) male regurgitating pellet, in forest, Pays de Loire, France

Sven Zacek / Ural owl (Strix uralensis) female and chick at nest, female regurgitating pellet. Southern Estonia. May.

Dave Bevan / Male Pied flycatcher (Ficedula hypoleuca) perched on a branch, disgorges pellet before flying out of frame, Carmarthenshire, Wales, UK, May.

Philippe Clement / Close up of regurgitated pellet from great skua (Stercorarius skua) showing seabird prey remains like bones and feathers, Scotland, UK, May.

Philippe Clement / Close up of regurgitated pellet from great skua (Stercorarius skua) showing seabird prey remains like bones and feathers, Scotland, UK, May.

Steven David Miller / Sand bubble patterns created by Sand bubbler crabs (Scopimera inflata), Cape Hillsborough National Park, Queensland, Australia. September.

Adrian Davies / Barn owl (Tyto alba) pellets, contents of approximately six pellets containing skulls and bones of voles, mice and shrews, and cockchafer beetle. UK. March.

Markus Varesvuo / Hawk Owl (Surnia ulula) regurgitating pellet before eating vole prey, Helsinki, Finland, December.

Philippe Clement / Short-eared owl (Asio flammeus) regurgitated pellet containing the remains of birds and mice, Scotland, UK, May

Sven Zacek / Wood sandpiper (Tringa glareola) regurgitating a pellet on the shore of a small lake in Southern Estonia.

Sven Zacek / Wood sandpiper (Tringa glareola) regurgitating a pellet on the shore of a small lake, Southern Estonia, May.

SCOTLAND: The Big Picture / Female Merlin (Falco columbarius) coughing up a pellet, Cairngorms National Park, Scotland, UK, June.

Loic Poidevin / European roller (Coracias garrulus) regurgitating pellet perched on barbed wire fence, Alentero, Spain, April.

Loic Poidevin / Common kingfisher (Alcedo atthis) regurgitating pellet, Le Teich, Gironde, France, September.

Charlie Summers / Northern carmine bee-eater (Merops nubicus) regurgitating pellet, Selous Game Reserve, Tanzania.

Roger Powell / European bee-eater (Merops apiaster) opening its beak wide before ejecting a pellet from it. Guerreiro, Castro Verde, Alentejo, Portugal, May..

Loic Poidevin / Common bee-eater (Merops apiaster) regurgitating pellet, Bouches du Rhone, France, May

Michel Poinsignon / Eagle owl (Bubo bubo) pellet containing remains of its prey, Luxembourg. March.

Fred Olivier / South polar skua (Stercorarius maccormicki) chick at nest site, regurgitates pellet, with parent in the foreground, Antarctica.

Eric Medard / Little owl (Athene noctua) coughing up a pellet, France, July

Eric Medard / Little owl (Athene noctua) coughing up a pellet, France, July

Eric Medard / Little owl (Athene noctua) during the day on a wall, coughing up a pellet, France, October

Eric Medard / Montagu's Harrier (Circus pygargus) male coughing up pellet, France, June

David Tipling / 2020VISION / Reed warbler (Acrocephalus scirpaceus) feeding twelve day old Cuckoo (Cuculus canorus) chick at nest and removing faecal pellet, Norfolk, England, UK, May

Michel Poinsignon / Great tit (Parus major) flying flying from nest carrying faecal pellet, Lorraine, France, March.

Todd Mintz / Snowy owl (Bubo scandiaca) male expelling pellet on the Canadian prairie, Saskatchewan, Canada, March, sequence 3/3

Todd Mintz / Snowy owl (Bubo scandiaca) male expelling pellet on the Canadian prairie, Saskatchewan, Canada, March, sequence 2/3

Todd Mintz / Snowy owl (Bubo scandiaca) male expelling pellet on the Canadian prairie, Saskatchewan, Canada, March, sequence 1/3

Ingo Arndt / Rat bait, South Georgia Heritage Trust Rat Eradication Project, South Georgia 2011

Laurie Campbell / Tawny owl (Strix aluco) regurgitated pellet, Berwickshire, Scotland, October

Pete Oxford / Faecal pellet of Galapagos Giant Tortoise (Chelonoidis nigra) Wolf Volcano, Isabela Island, Galapagos

Andy Sands / Short Eared Owl (Asio flammeus) coughing up an owl pellet. Lincolnshire, England, UK, February.

Andy Sands / Short Eared Owl (Asio flammeus) coughing up an owl pellet. Lincolnshire, England, UK, February.

Adrian Davies / Regurgitated pellet of Tawny owl (Strix aluco) showing remains of prey, Sussex, England, UK