Andres M. Dominguez / Firecrest (Regulus ignicapilla) perched on lichen covered branch, Sierra de Grazalema Natural Park, southern Spain, May.

Markus Varesvuo / Yellow browed warbler (Phylloscopus inornatus) perched on twig, Uto, Finland, September.

Alan Murphy / Golden-crowned Kinglet (Regulus satrapa) male, Texas

Markus Varesvuo / Goldcrest (Regulus regulus) perched amongst juniper berries, Espoo, Finland, February

Grzegorz Lesniewski / Firecrest (Regulus ignicapilla) perched on fir branch. Bieszczady National Park, the Carpathians, Poland, April.

David Tipling / 2020VISION / Firecrest (Regulus ignicapillus) male singing, Norfolk, UK, April. Did you know?

Stephen Dalton / Goldcrest ( Regulus regulus) in flight, UK

David Tipling / Firecrest {Regulus ignicapillus} perched, Norfolk, UK, April

Andy Sands / Goldcrest (Regulus regulus) male in full song, Buckinghamshire, England, UK.

Dave Watts / Firecrest (Regulus ignicapillus) Adult feeding chicks at nest, France

Claus Meyer / Striped Manakin (Machaeropterus regulus) couple perching on branch, Atlantic Forest ecosystem, Brazil

Nigel Bean / Goldcrest, England UK

Bruno D'Amicis / Firecrest (Regulus ignicapillus) female feeding on bark of old growth Beech (Fagus sylvatica) forest tree. Abruzzo, Lazio and Molise National Park / Parco Nazionale d'Abruzzo, Lazio e Molise UNESC...

Karine Aigner / Golden-crowned kinglet (Regulus satrapa) in a mist net. Block island, Rhode Island, USA.

Karine Aigner / Portrait of a Ruby-crowned kinglet (Regulus calendula) with white background, Block island, Rhode Island, USA. Bird caught during scientific research.

Karine Aigner / Portrait of a Golden-crowned kinglet (Regulus satrapa) with white background, Block island, Rhode Island, USA. Bird caught during scientific research.

Andres M. Dominguez / Firecrest (Regulus ignicapillus) perched in Common hawthron. Grazalema, Andalusia, Spain, April.

Andres M. Dominguez / Goldcrest (Regulus regulus) perched on maple, Ordesa y Monte Perdido National Park, Huesca, Spain, October.

Jussi Murtosaari / Goldcrest (Regulus regulus) with insect prey, Finland, September

Jussi Murtosaari / Goldcrest (Regulus regulus), Finland, September

Jussi Murtosaari / Goldcrest (Regulus regulus), male, Finland, September

Jussi Murtosaari / Goldcrest (Regulus regulus), male, Finland, September

Jussi Murtosaari / Goldcrest (Regulus regulus) with fly prey, Finland, September

Alan Murphy/ BIA / Golden-crowned Kinglet (Regulus satrapa) male calling, British Columbia, Canada

David Kjaer / Firecrest (Regulus ignicapilla) singing,Wiltshire, England, UK, April.

Andres M. Dominguez / Firecrest (Regulus ignicapillus), Cadiz, Andalusia, Spain, April.

Andres M. Dominguez / Firecrest (Regulus ignicapillus) perched on a Giant orchid (Himantoglossum robertianum) Cadiz, Andalusia, Spain, March.

Andres M. Dominguez / Firecrest (Regulus ignicapillus) perched on a frozen branch, Cadiz, Andalusia, Spain, January.

David Tipling / Firecrest (Regulus ignicapilla) male perched, Sheringham, Norfolk, UK, April.

Andy Sands / Firecrest (Regulus ignicapillus) perched in Oak tree, Hampshire, England, UK, May

David Tipling / Goldcrest (Regulus regulus) migrant species, North Norfolk, UK October

David Tipling / Goldcrest (Regulus regulus) winter migrant, North Norfolk, UK October

David Kjaer / Firecrest (Regulus ignicapillus) male, Wiltshire, UK April

David Kjaer / Firecrest (Regulus ignicapillus) male, Wiltshire, UK April

David Kjaer / Firecrest (Regulus ignicapillus) male, Wiltshire, UK April

Andres M. Dominguez / Goldcrest (Regulus regulus) in pine tree, Ordesa y Monte Perdido National Park, Huesca, Spain, October.

Kerstin Hinze / Goldcrest (Regulus regulus) perched, Lower Saxony, Germany. October.

Kerstin Hinze / Goldcrest (Regulus regulus) perched, Lower Saxony, Germany. October.

Kerstin Hinze / Goldcrest (Regulus regulus) perched, Lower Saxony, Germany.

David Pattyn / Great Crested Grebe (Podiceps cristatus) spreading its wings wide and keeping crest erect to impress its partner during courtship. The Netherlands. April.

David Pattyn / Great Crested Grebe (Podiceps cristatus) spreading its wings wide and keeping crest erect to impress its partner during courtship. The Netherlands. April.

David Kjaer / Goldcrest (Regulus regulus) male, Wiltshire, UK, April.

David Kjaer / Firecrest (Regulus ignicapillus) male, Wiltshire, UK, April.

David Kjaer / Firecrest (Regulus ignicapillus) male, Wiltshire, UK, April.

David Kjaer / Firecrest (Regulus ignicapillus) male, Wiltshire, UK, April.

Markus Varesvuo / Goldcrest (Regulus regulus), Uto, Finland, October.

Markus Varesvuo / Goldcrest (Regulus regulus), Uto, Finland, October.

Hanne & Jens Eriksen / Golden crowned kinglet (Regulus satrapa) looking for food, New Jersey, USA, October.

David Tipling / Goldcrest (Regulus regulus) perched, Norfolk, UK, April.

David Tipling / Firecrest (Regulus ignicapilla) male, Sheringham, Norfolk, UK, April.

Jussi Murtosaari / Goldcrest (Regulus regulus) Uto, Korppoo, Parainen / Lansi-Turunmaa, Lounais-Suomi, Varsinais-Suomi / Southwestern Finland, Finland. February

Jussi Murtosaari / Goldcrest (Regulus regulus) Uto, Korppoo, Parainen / Lansi-Turunmaa, Lounais-Suomi, Varsinais-Suomi / Southwestern Finland, Finland. February

Alan Murphy / Ruby-crowned Kinglet (Regulus calendula), Texas

Glenn Bartley / Ruby-crowned Kinglet (Regulus calendula), Manitoba, Canada

Markus Varesvuo / Female Goldcrest (Regulus regulus) perched, Espoo, Finland, February

Markus Varesvuo / Goldcrest (Regulus regulus) on pine tree. Liljendahl, Finland, February

Markus Varesvuo / Goldcrest (Regulus regulus) on branch. Liljendahl, Finland, February

Walter Soestbergen / Goldcrest (Regulus regulus), Utrecht, Netherlands

Robin Chittenden / Goldcrest (Regulus regulus) Norfolk, England, UK, November.

David Tipling / Firecrest (Regulus ignicapillus) perched, Norfolk, England, UK, April.

Donald M. Jones / Golden-crowned Kinglet (Regulus satrapa) male in Grand Fir (Abies grandis) tree, Montana

Glenn Bartley / Ruby-crowned Kinglet (Regulus calendula), British Columbia, Canada

Nick Saunders / Golden-crowned Kinglet (Regulus satrapa) singing, Saskatoon, Saskatchewan, Canada

Matthew Studebaker / Golden-crowned Kinglet (Regulus satrapa) calling, Michigan

Thomas Hinsche / Common Firecrest (Regulus ignicapilla), Saxony-Anhalt, Germany

Ralph Martin / Goldcrest (Regulus regulus), Baden-Wurttemberg, Germany

Ralph Martin / Firecrest (Regulus ignicapilla), Baden-Wurttemberg, Germany

Walter Soestbergen / Goldcrest (Regulus regulus), Utrecht, Netherlands

Ralph Martin / Firecrest (Regulus ignicapilla), Baden-Wurttemberg, Germany

Alan Murphy / Ruby-crowned Kinglet (Regulus calendula) calling, Texas

Alan Murphy / Ruby-crowned Kinglet (Regulus calendula), Texas

Glenn Bartley / Ruby-crowned Kinglet (Regulus calendula), British Columbia, Canada

Glenn Bartley / Ruby-crowned Kinglet (Regulus calendula), British Columbia, Canada

Robin Chittenden / Goldcrest (Regulus regulus) Norfolk, UK,

Alan Williams / Goldcrest (Regulus regulus) perched on dead Gorse bush at edge of conifer forest, North Wales, UK, May.

Alan Williams / Goldcrest (Regulus regulus) singing in dead Gorse bush at edge of conifer forest, North Wales, UK, May.

Alan Williams / Goldcrest (Regulus regulus) singing in conifer forest, North Wales, UK, May.

Alan Williams / Goldcrest (Regulus regulus) singing in conifer forest, North Wales, UK, May.

Alan Williams / Goldcrest (Regulus regulus) perched in conifer forest, North Wales, UK, May.

Alan Williams / Goldcrest (Regulus regulus) perched singing in conifer forest, North Wales, UK, May.

Loic Poidevin / Common firecrest (Regulus ignicapilla) on branch amongst salt cedar (Tamarix gallica) Breton marsh, West France, December

Loic Poidevin / Common firecrest (Regulus ignicapilla) on branch amongst salt cedar (Tamarix gallica) Breton marsh, West France, December

Markus Varesvuo / Goldcrest (Regulus regulus) Uto Finland September

Markus Varesvuo / Goldcrest (Regulus regulus) flying up towards pine tree, Uto Finland September

Markus Varesvuo / Goldcrest (Regulus regulus) eating berries, Uto Finland September

Wild Wonders of Europe / Préau / Man holding Firecrest (Regulus ignicapillus) caught in net for ringing in allotment, Grande-Synthe, Dunkirk, France, September 2010, model released

Wild Wonders of Europe / Préau / Hand holding Firecrest (Regulus ignicapillus) caught in net for ringing in allotment, Grande-Synthe, Dunkirk, France, September 2010, model released

Wild Wonders of Europe / Préau / Man measuring Firecrest (Regulus ignicapillus) wing length, caught in net in allotment, Grande-Synthe, Dunkirk, France, September 2010, model released

Wild Wonders of Europe / Préau / Man blowing feathers on underside of Firecrest (Regulus ignicapillus) caught in net in allotment, Grande-Synthe, Dunkirk, France, September 2010, model released

Wild Wonders of Europe / Préau / Man ringing Firecrest (Regulus ignicapillus) caught in net in allotment, Grande-Synthe, Dunkirk, France, September 2010, model released

Wild Wonders of Europe / Préau / Firecrest (Regulus ignicapillus) caught in mist net for ringing, in allotment, Grande-Synthe, Dunkirk, France, September 2010

Markus Varesvuo / Goldcrest (Regulus regulus) clinging upside down to Juniper twig, Uto, Finland, October

Markus Varesvuo / Goldcrest (Regulus regulus) perched on twig with dried dead leaves, Uto, Finland, October

Donald M. Jones / Ruby-crowned Kinglet (Regulus calendula) male, Kalispell, Montana

Donald M. Jones / Ruby-crowned Kinglet (Regulus calendula) male calling, Kalispell, Montana

Donald M. Jones / Golden-crowned Kinglet (Regulus satrapa) male, Bull River Valley, Montana