Pied avocet
Template:Short description Template:Speciesbox
The pied avocet (Recurvirostra avosetta) is a species of wader in the Recurvirostridae family, the only member of the genus Recurvirostra found in Europe.
This characteristic wader of coastal lagoons and marshes is easily recognizable by its long, upturned bill, long legs, and striking black-and-white plumage. Measuring approximately Template:Cvt in length with a wingspan of about Template:Cvt, it is a relatively large species that feeds on various invertebrates in water and mudflats, captured using its distinctive bill. It typically nests in colonies of 10 to 70 pairs on islets or dikes near water, laying usually four eggs in a simple, shallow scrape in the sand. Highly territorial when defending its chicks against conspecifics or predators—such as various raptors, corvids, and mammals—the pied avocet has a lifespan of about 20 years, with a record of 27 years.
The species has a wide distribution, spanning western Europe, central Asia, the Indian subcontinent, and Africa. Part of its population is migratory, undertaking long journeys south to its wintering grounds, while others are resident. In France, it is found along the English Channel, Atlantic coast, and Mediterranean, with northern populations joining in winter, while some individuals winter in Southern Europe or Africa.
Described by Carl Linnaeus in 1758, the pied avocet is one of four species in its genus, the others inhabiting different continents. Classified as Least Concern (LC) by the IUCN due to its extensive range and relatively large population, it nonetheless faces threats from anthropogenic factors such as habitat destruction, climate change, and pollution. Numerous scientific programs aim to better understand its biology, particularly its migratory routes, to enhance its protection.
Description
Template:Main Template:Multiple image Adults have a striking black-and-white plumage, with a black cap extending to the back of the neck.<ref name="OiseauxEurope">Template:Cite book</ref> The primaries are black, with the base of the inner primaries white, while the secondary coverts are dark grey. The rectrices are pale grey-brown in the middle and white elsewhere.<ref name="geroudet">Template:Cite book</ref> The species shows no seasonal plumage variation. The tail is white, and the legs are bluish. The long, black beak is slender and upturned.<ref name="OiseauxEurope" />
Sexual dimorphism is subtle and difficult to discern in the field.<ref name="INPNCahierHabitatOiseaux">Template:Cite web</ref> The male's bill is longer and less curved, while the female's is shorter and more distinctly curved.<ref name="Svensson">Template:Cite book</ref> The black markings on the female's head may occasionally appear browner and less distinct.<ref name="Svensson" /> Males are generally larger than females, with a red or reddish-brown iris, while females have a hazel-brown iris.<ref name="geroudet" />
In flight, the wingtips and shoulders are black, and the legs extend beyond the tail.<ref name="OiseauxEurope" />
Chicks are covered in pale grey-brown down, finely speckled with black, with black patterns on the head, four rows of black spots on the back, and a white underbelly tinged yellowish at the neck and belly. Their iris is dark brown.<ref name="geroudet" />
Juveniles have dingy grey wing coverts,<ref name="OiseauxEurope" /> with back and scapular feathers vermiculated with reddish-brown.<ref name="INPNCahierHabitatOiseaux" /> Their legs are greyish.<ref name="Svensson" /> By their first summer, the primaries of juveniles appear very worn and brownish.<ref name="Svensson" /> After their first moult, which occurs by late September, juveniles resemble adults.<ref name="INPNCahierHabitatOiseaux" />
Two moults occur: a partial moult in February–March before breeding and a complete moult after breeding, from July to October.<ref name="INPNCahierHabitatOiseaux" />
Measurements
The pied avocet measures between Template:Cvt in length,<ref name="Svensson2">Template:Cite book</ref> with a wingspan of Template:Cvt, occasionally up to Template:Cvt.<ref name="MNHNFicheDescription">Template:Cite web</ref> The wing of an adult male measures Template:Cvt, while that of a female measures Template:Convert.<ref name="demongin">Template:Cite book</ref>
The bill measures Template:Cvt in males and is slightly shorter in females, ranging from Template:Cvt. The legs extend beyond Template:Cvt, with a tarsus of Template:Cvt in males and Template:Cvt in females.<ref name="Svensson2" /><ref name="demongin" /> The tail measures Template:Cvt in adult males and Template:Cvt in adult females.<ref name="demongin" />
The weight ranges from Template:Cvt, with an average of Template:Cvt.<ref name="INPNCahierHabitatOiseaux2">Template:Cite web</ref>
Behaviour
This avocet forages in shallow brackish water or on mud flats, often scything its bill from side to side in water (a feeding technique that is unique to the avocets).<ref name="Moreira1995" /><ref name="geroudet4">Template:Cite book</ref> It mainly eats crustaceans and insects.
Its breeding habitat is shallow lakes with brackish water and exposed bare mud. It nests on open ground, often in small groups, sometimes with other waders. Three to five eggs are laid in a lined scrape or on a mound of vegetation.<ref name="geroudet3">Template:Cite book</ref>
Vocalizations
The contact and alarm calls, often emitted by adults when chicks are threatened, are a fluty whistle, sometimes plaintive, resembling plut-plut-plutt or klup-klup-klup.<ref name="Svensson3">Template:Cite book</ref> Paul Géroudet notes kvit-kvit-kvit when birds are excited, as well as krit-krit or kvèt. Near predators, avocets may emit kriyu. They also produce soft buk-buk during chick-rearing or glouglou... grrugrrugrru with mates during breeding.<ref name="geroudet2">Template:Cite book</ref>
Diet and feeding techniques

The pied avocet primarily feeds on small benthic invertebrates, such as annelids, small crustaceans like Corophium, oligochaete and polychaete worms (e.g., Hediste diversicolor or Polydora species), and bivalve molluscs.<ref name="AtlasOiseauxFrance">Template:Cite book</ref><ref name="INPNCahierHabitatOiseaux3">Template:Cite web</ref> It also consumes small insects (midges, beetles) measuring Template:Cvt.<ref name="delhoyo">Template:Cite book</ref><ref name="johnsgard">Template:Cite book</ref><ref name="geroudet2" /> Daily food intake averages Template:Cvt per individual.<ref name="geroudet2" />
Chironomid larvae are a key food source during breeding and wintering in salt marshes.<ref name="chironomes">Template:Cite journal</ref>
It occasionally eats small fish, seeds, and small roots.<ref name="delhoyo" /><ref name="urban">Template:Cite book</ref>
It uses its bill to probe the sediment surface, making lateral pecks to find prey, or catches them by sight.<ref name="INPNCahierHabitatOiseaux3" /><ref name="geroudet2" /> In group feeding, lateral pecks are faster and nearly continuous.<ref name="geroudet2" /> Adults feed in water depths of Template:Cvt.<ref name="epaisseureau">Template:Cite journal</ref> It may also peck on beaches or swim in deeper water, dipping its head like a duck.<ref name="Svensson3" /> In groups, it may extend its neck, sweep its bill through the mud, and repeat the motion.<ref name="geroudet2" />
Locally, it may align its circadian rhythm with tides, feeding at night in salt marshes, such as in the Guérande Peninsula.<ref name="chironomes" />
Philopatry
The pied avocet is philopatric. This has been demonstrated through banding studies in Atlantic sites like the Gulf of Morbihan, Guérande Marshes, and Müllembourg Marshes on Noirmoutier Island, where some banded birds returned to nest.<ref name="avocettehyeres">Template:Cite journal</ref> Survival and return rates in the Atlantic range from 48–75% (average 58%) for first-year birds and 78–100% (average 90%) for adults, depending on the year.<ref name="INPNCahierHabitatOiseaux3" />
Philopatry may explain increased breeding populations at some sites, as many new breeders are offspring from previous seasons.<ref name="avocettehyeres" /> When sites reach capacity, new colonies form elsewhere, boosting populations.<ref name="hill">Template:Cite journal</ref>
Reproduction
Nest and eggs
The species is semi-colonial.<ref name="semicolo">Template:Cite journal</ref> It nests in dense colonies of 10–70 pairs,<ref name="johnsgard" /> sometimes up to 200 in multiple groups,<ref name="geroudet2" /> or as isolated pairs. In Algeria, islets with 798 nests have been recorded.<ref name="menouar">Template:Cite journal</ref> It is monogamous, with pairs forming soon after arriving at breeding sites.<ref name="INPNCahierHabitatOiseaux3" /> It often nests in mixed colonies with gulls and waders, especially terns.<ref name="geroudet2" />
Pairs perform rituals to bond, such as tossing debris, pretending to drink, or bowing side by side.<ref name="geroudet2" /> Mating involves the male preening after dipping its bill in water, while the female leans forward. The male moves around the female, repeatedly dipping its bill. During copulation, the female sways her neck laterally.<ref name="geroudet2" /> Post-copulation, the pair crosses bills, and the male drapes his wing over the female before separating.<ref name="geroudet2" />
Some males have been observed attempting to mate with inanimate objects.<ref name="accouplementobjet">Template:Cite journal</ref>
The nest is a shallow scrape, averaging Template:Cvt in diameter, ranging from Template:Cvt,<ref name="menouar" /> and Template:Convert deep.<ref name="geroudet2" /> It is placed near water,<ref name="Svensson3" /> up to Template:Cvt from the shore, preferably on islets or dikes, in sand, short vegetation, or debris,<ref name="urban" /><ref name="johnsgard" /> but never in mud.<ref name="bouealgerie">Template:Cite journal</ref><ref name="boueiran">Template:Cite journal</ref> Islets improve hatching success by reducing predation.<ref name="lengyel">Template:Cite journal</ref> Unlike the Eurasian oystercatcher, the avocet does not adjust nest size for water level changes.<ref name="cuervo">Template:Cite journal</ref>
Nests often include shell fragments, particularly Cerastoderma glaucum, and vegetation like samphire, grasses, goosefoots, sea-lavender, bromes, widgeon grass, or saltmarsh bulrush.<ref name="plumenaturaliste">Template:Cite journal</ref>
In colonies, nests are typically spaced Template:Cvt to Template:Cvt, though in an Iranian colony, the average was Template:Cvt.<ref name="urban" /><ref name="hayman">Template:Cite book</ref><ref name="boueiran" />
Egg-laying occurs from early April to early July,<ref name="avocettehyeres" /> peaking from mid-April to mid-May.<ref name="ponte">Template:Cite journal</ref> Clutches range from 69 to 92 days,<ref name="ponte" /> typically with three to five eggs, occasionally more due to intraspecific parasitism.<ref name="avocettehyeres" /><ref name="INPNCahierHabitatOiseaux3" /><ref name="parasitisme">Template:Cite journal</ref> Eggs measure Template:Cvt and weigh about Template:Cvt.<ref name="BTO">Template:Cite journal</ref> Incubation lasts 19–34 days, averaging 23 days.<ref name="incubation">Template:Cite journal</ref> Both parents incubate, with a ritual involving debris-tossing and sliding under the incubating bird to take over. This ritual diminishes over time. The non-incubating parent may feed up to Template:Cvt from the colony.<ref name="geroudet2" />
The species typically lays one clutch per year, with replacement clutches if eggs are lost, usually to predation. Hatching success varies by site and year, ranging from 54–78% in the Olonne Marsh<ref name="ponte" /> and 8–59% in the Séné Marshes.<ref name="ponte" />
Chick rearing and productivity

Chicks are nidifugous, leaving the nest after the last egg hatches.<ref name="INPNCahierHabitatOiseaux3" /> They remain in the nest for at least five hours post-hatching.<ref name="stanescu">Template:Cite journal</ref> In the first hours, they alternate between sheltering under parents and exploring nearby.<ref name="adret2">Template:Cite journal</ref> Within 72 hours, the family moves to nearby feeding areas.
Both parents protect chicks from predators and weather.<ref name="INPNCahierHabitatOiseaux3" /> The species is highly territorial during chick-rearing, defending feeding and rearing areas against other birds.<ref name="adret">Template:Cite journal</ref> Adults use distraction displays, such as feigning a broken wing or swooping at intruders.<ref name="geroudet2" /> Chicks hide in samphire, flee across mudflats, or swim when threatened.
Each family has a stable rearing territory, proportional to chick number, ranging from Template:Cvt.<ref name="adret" /> Stability depends on food and space availability. Asynchronous hatching may optimize mudflat use.<ref name="adret" />
Chicks feed in exposed mudflats or water up to Template:Cvt deep. They may travel significant distances shortly after hatching.<ref name="epaisseureau" />
Chicks fledge and become independent 35–42 days after hatching.<ref name="INPNCahierHabitatOiseaux3" /> Rarely, chicks are raised by other species, such as Eurasian Oystercatchers in Somme Bay in 1981, where a chick was fed for two months, adopting oystercatcher behaviors.<ref name="huitrier">Template:Cite journal</ref>
Reproductive success varies by year and site, with productivity of 0.49–0.52 fledglings per pair on the Atlantic and Channel coasts,<ref name="vanimpe">Template:Cite journal</ref><ref name="avosomme">Template:Cite journal</ref> 0.45–0.63 in Languedoc colonies, and 0.04–0.22 in Camargue.<ref name="repromedit">Template:Cite journal</ref>
Sexual maturity varies: 25% of French birds breed in their first year, 40% in their second, while North Sea birds mature between two and five years.<ref name="maturite">Template:Cite journal</ref><ref name="maturite2">Template:Cite journal</ref> Generally, maturity is reached at 2–3 years.<ref name="geroudet2" />
First-year mortality is 50–60%, dropping to 20–30% in subsequent years.<ref name="geroudet2" /> The maximum recorded lifespan for a wild banded bird is Template:Convert,<ref name="INPNCahierHabitatOiseaux3" /> with another observed nearly 25 years post-banding,<ref name="BTO" /> though the average is 12 years.<ref name="geroudet2" />
Reproductive failure factors
The main causes of reproductive failure are intraspecific conflicts<ref name="echecintra">Template:Cite journal</ref><ref name="repromedit" /> and predation by other species.
Predators include corvids like the carrion crow (Corvus corone) and common magpie (Pica pica), gulls such as the European herring gull (Larus argentatus) in the Atlantic<ref name="avosomme" /> and yellow-legged gull (Larus michahellis) in the Mediterranean, and raptors, particularly the common kestrel (Falco tinnunculus), which targets chicks.<ref name="avocettehyeres" /><ref name="INPNCahierHabitatOiseaux3" /> The peregrine falcon (Falco peregrinus) preys on adults, while the western marsh harrier (Circus aeruginosus) and white stork (Ciconia ciconia) may take chicks.<ref name="adret2" /><ref name="echecintra" /> Mammalian predators include the red fox (Vulpes vulpes), possibly the wild boar (Sus scrofa), mustelids, the brown rat (Rattus norvegicus), and stray dogs.<ref name="avocettehyeres" /><ref name="INPNCahierHabitatOiseaux3" /> Increased gull populations can disrupt colonies.<ref name="provence">Template:Cite book</ref>
Nests may be destroyed by flooding<ref name="INPNCahierHabitatOiseaux3" /> or trampled by livestock.<ref name="goutner">Template:Cite journal</ref> Poor water quality or inappropriate salinity can limit food availability,<ref name="avosomme" /><ref name="hill" /> as can excessive salinity.<ref name="hill" />
Spatial competition with other gull-wader species, such as the black-headed gull (Chroicocephalus ridibundus), Mediterranean gull (Ichthyaetus melanocephalus), European herring gull, gull-billed tern (Gelochelidon nilotica), sandwich tern (Thalasseus sandvicensis), common tern (Sterna hirundo), and little tern (Sternula albifrons), can hinder breeding.<ref name="goutner" /><ref name="italy">Template:Cite journal</ref>
Chick dispersal for food increases mortality risk,<ref name="hill" /><ref name="bouche">Template:Cite journal</ref> and harsh weather affects chicks aged two to three weeks.<ref name="avosomme" />
Parasites
The species hosts parasites like Giardia<ref name="giardia">Template:Cite journal</ref> and Eurycestus avoceti, first observed in the American avocet and later in Camargue individuals, with the crustacean Artemia salina as an intermediate host.<ref name="Eurycestus1">Template:Cite journal</ref><ref name="Eurycestus2">Template:Cite journal</ref>
Habitats

The species frequents coastal habitats. In winter, it gathers in groups on soft substrates like brackish or saline bays, sandbanks, estuaries, lagoons, deltas, or intertidal mudflats, used for resting and feeding.<ref name="Svensson3" /><ref name="AtlasOiseauxFrance" /> During high tides, it may stay in water or gather on salt marshes or cordgrass meadows.<ref name="INPNCahierHabitatOiseaux3" /> It also occurs in shallow lakes, ponds, salt marshes, or various floodplains, rarely on inland lakes or rivers, and sometimes feeds on agricultural land.<ref name="delhoyo" /><ref name="urban" />
During breeding, Mediterranean populations use similar habitats.<ref name="INPNCahierHabitatOiseaux3" /> On the Atlantic coast, it inhabits wetlands, natural or artificial, with sparse vegetation and shallow water pockets with mud, sand, or clay islets,<ref name="snow">Template:Cite book</ref> or dikes with samphire.<ref name="sansouire">Template:Cite book</ref> Preferred islets are elongated, Template:Cvt long and Template:Cvt wide, offering a clear view of nearby water.<ref name="avosomme" />
Locally, it may occupy port facilities, such as in Somme Bay,<ref name="INPNCahierHabitatOiseaux3" /> former polders, or sugar refinery settling basins in northern France.<ref name="sucrerie">Template:Cite journal</ref> It has been observed breeding near hunting blinds.<ref name="huttechasse">Template:Cite journal</ref> It breeds up to Template:Cvt in altitude in Anatolia.<ref name="geroudet2" />
Key breeding habitat features include gradually decreasing water levels to expose feeding areas and high salinity to limit vegetation growth.<ref name="johnsgard" />
The EUNIS lists brackish and saline coastal lagoons and estuaries as key habitats.<ref name="EUNIS">Template:Cite book</ref>
Distribution
The pied avocet is a Turano-Mediterranean species, found in the Palearctic. Its fragmented range spans European coastlines from southern Scandinavia and the Baltic states (e.g., Estonia since 1964) to the Iberian Peninsula, the Mediterranean, Black Sea, and eastern European plains (Ukraine, Bulgaria, Romania, Hungary).<ref name="delhoyo2">Template:Cite book</ref><ref name="hayman2">Template:Cite book</ref> Major European populations are in the Netherlands, Germany, Denmark, Spain (southern and Ebro Delta), Italy (Po Delta and Sardinia), France, and Russia.<ref name="AtlasOiseauxFrance2">Template:Cite book</ref> It occurs on southern England coasts (about 150 pairs in 1979),<ref name="geroudet5">Template:Cite book</ref> having returned to breed in 1947 in Suffolk’s Minsmere RSPB reserve after disappearing in the mid-19th century.<ref name="MondeAnimal">Template:Cite book</ref><ref name="Chants">Template:Cite book</ref>
In Asia, it ranges from Turkey (Anatolia) to northern Mongolia, northern China, southern Russian Far East, Kazakhstan, and Middle Eastern countries (Iran, Iraq, Jordan).<ref name="geroudet5" /> It is patchily distributed in the Gulf states, Pakistan, and the Indian subcontinent.<ref name="UICN">Template:Cite web</ref>
In Africa, it occurs along the Mediterranean coast of North Africa, the Red Sea, and Atlantic coast to Senegal and northern Guinea, covering parts of the Sahel, East Africa, and southern Africa.<ref name="INPNCahierHabitatOiseaux4">Template:Cite web</ref><ref name="UICN" />
Northern European (Netherlands to Scandinavia) and eastern Asian populations are migratory.<ref name="Svensson4">Template:Cite book</ref> Western European birds winter in West Africa (Senegal, Gambia, Niger) and Mediterranean countries, especially Spain and Portugal (one-third of migratory European birds).<ref name="INPNCahierHabitatOiseaux4" /> Eastern European birds winter in Niger, Chad, Sudan, and the Red Sea.<ref name="geroudet5" /> Some overwinter from Denmark to the Netherlands, England to Ireland.<ref name="geroudet5" /> Asian populations winter in East Africa or the Indian subcontinent.<ref name="UICN" /> Migratory groups of 5–30 birds move from August to October and return between March and May.<ref name="urban2">Template:Cite book</ref><ref name="delhoyo2" />
Mediterranean, some African, and Gulf populations are sedentary.<ref name="UICN" /><ref name="delhoyo2" /> Some Camargue birds winter in Morocco and Tunisia.<ref name="geroudet5" />
During migration, transalpine flights occur (e.g., in Engadine), but inland sightings are rare. Individuals have been recorded as far as the Faroe Islands, Azores, and Canary Islands.<ref name="geroudet5" />
In France
Historical presence

The Pied Avocet was present in France during the Roman Gaul period, evidenced by bones found in a waste pit in Lattes, Hérault, alongside other bird species.<ref name="oslattes">Template:Cite journal</ref> Later, a single specimen was found in 14th-century deposits in Abbeville, Somme.<ref name="restessomme">Template:Cite journal</ref>
It was noted as breeding in Camargue and Languedoc only from the early 20th century.<ref name="Mayaud">Template:Cite book</ref> It established breeding on the Atlantic coast from the 1950s, starting in Vendée in 1952, reaching Morbihan by 1983, and the English Channel and Somme Bay in the 1970s.<ref name="fichehistorique">Template:Cite journal</ref><ref name="Yeatman">Template:Cite book</ref> It likely bred in France before the 20th century, possibly colonizing or recolonizing spontaneously from its Mediterranean range.<ref name="fichehistorique" />
Current presence
The species is present year-round in France. In winter, northern migratory populations bolster local numbers, primarily along the Atlantic coast from the Gironde Estuary to Morbihan, hosting 80–90% of the national wintering population.<ref name="pophiverfrance">Template:Cite journal</ref><ref name="hivernageavocette">Template:Cite journal</ref> It is less common along the English Channel, mainly in Somme Bay and Lower Normandy,<ref name="avocetteseine">Template:Cite journal</ref> and in the Mediterranean, primarily in Camargue and Montpellier ponds.<ref name="AtlasOiseauxFrance2" /> Only about ten French sites exceed international significance thresholds (730 individuals for the Atlantic, 470 for the Mediterranean).<ref name="AtlasOiseauxFrance2" /> It is occasionally seen inland in the northwest, particularly the Loire Valley, during late migrations in December.<ref name="AtlasOiseauxFrance2" />
During breeding, it occurs in three main regions. The first is along the English Channel coast, with colonies in Normandy (about 300 pairs), Somme Bay (about 170 pairs), Nord-Pas-de-Calais, and inland in Nord and Aisne.<ref name="AtlasOiseauxFrance2" />
The second region is the Atlantic coast, from Gulf of Morbihan to the Gironde Estuary. Vendée hosts the largest population with 1,300 pairs (30% of the national breeding population), followed by Loire-Atlantique with 500 pairs and Charente-Maritime with 400 pairs.<ref name="AtlasOiseauxFrance2" />
The third region is the Mediterranean coast, from La Palme salt flats in Aude to the Étang de Berre in Bouches-du-Rhône. An isolated population exists at Hyères Salt Flats in Var.<ref name="avocettehyeres2">Template:Cite journal</ref> Bouches-du-Rhône hosts 550 pairs, Aude 400 pairs.<ref name="AtlasOiseauxFrance2" /> Provence-Alpes-Côte d'Azur accounted for about 20% of France’s breeding population from 2003–2012.<ref name="vanderyeught">Template:Cite journal</ref> The species is absent from Corsica.
In Belgium
The species is distributed in the Zwin Nature Park, Antwerp, and Ghent, with over 480 breeding pairs.<ref name="geroudet5" />
In Britain
The pied avocet was extirpated as a breeding species in Great Britain by 1840.<ref name="BBC" /> Its successful recolonisation at Minsmere, Suffolk, in 1947 led to its adoption as the logo of the Royal Society for the Protection of Birds.<ref name="BWP" /> The pied avocet has spread inland and northwards and westwards in Britain since then and it has bred in Wales<ref name="NRW">Template:Cite web</ref> and in Scotland in 2018 at Skinflats.<ref name="RSPBScotland">Template:Cite web</ref> Avocets have been sighted wintering at Browhouses, Dumfries and Galloway.
Nomenclature and taxonomy
Etymology
The term "avocet" derives from the old Italian avosetta, attested in the 17th century, of unknown origin.<ref name="nomoiseaux">Template:Cite book</ref> In French, "avocette" stems from a 1760 error by Brisson, who replaced the "s" with a "c" in his bilingual Latin-French Ornithologie. This spelling was adopted by Buffon and standardized across languages.<ref name="nomoiseaux" />
The Latin name Recurvirostra avosetta derives from recurvus ("curved") and rostrum ("beak").<ref name="nomoiseaux" />
Taxonomy
The pied avocet was one of the many bird species originally described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae, where it was given the binomial name of Recurvirostra avosetta.<ref>Template:Cite book</ref> This species gets its English and scientific names from the Venetian word avosetta. It appeared first in Ulisse Aldrovandi's Ornithologia (1603).<ref name="ODBBN" /> While the name may refer to black and white outfits once worn by European advocates or lawyers, the actual etymology is uncertain.<ref name="ODBBN" /> Other common names include black-capped avocet, Eurasian avocet or just avocet.<ref name="avibase" />
It is one of four species of avocet that make up the genus Recurvirostra.<ref>Template:Cite book</ref> The genus name is from Latin recurvus, "curved backwards" and rostrum, "bill".<ref name="job">Template:Cite book</ref> A 2004 study combining genetics and morphology showed that it was the most divergent species in the genus.<ref>Template:Cite journal Supplementary Material</ref>
Phylogeny
The mitochondrial genome is 16,856 base pairs long.<ref name="phylogenie">Template:Cite journal</ref>
Fossil record
The species is recorded from the Middle and Late Pleistocene in the Mediterranean region, specifically in Sicily.<ref>Template:Cite journal</ref> It is also reported in northeastern Bulgaria, along the Black Sea coast, at the Yaylata site, in a deposit dating to the mid-Holocene, alongside other bird species.<ref>Template:Cite journal</ref>
Threats and conservation
Population size and demographic trends
The global population was estimated to be between 280,000 and 470,000 individuals in 2015. The overall population trend is unknown. In Europe, the species' population is estimated at between 117,000 and 149,000 adult individuals in 2015, equivalent to 58,400 to 74,300 breeding pairs, or, according to another source, between 38,000 and 57,000 pairs.<ref name="AtlasOiseauxFrance3">Template:Cite book</ref><ref name="UICN2">Template:Cite web</ref>
The Western European breeding population is estimated at 73,000 birds, wintering across Europe and Africa, from the Netherlands to northern Guinea, with 22,500 individuals in Sub-Saharan Africa.<ref name="INPNCahierHabitatOiseaux5">Template:Cite web</ref> France accounts for 13% of the European breeding population. During the 20th century, the species experienced a significant population increase in Europe, coupled with substantial geographic expansion, which began to stabilize in the early 21st century.<ref name="AtlasOiseauxFrance3" />
In France, between 2002 and 2006, an average of 20,800 wintering birds were observed, with significant interannual variations due to weather, with harsher winters reducing numbers. Between 2010 and 2013, the French wintering population ranged between 17,000 and 25,000 individuals,<ref name="AtlasOiseauxFrance3" /> representing nearly half of the European population.<ref name="avocettehyeres3">Template:Cite journal</ref> Since 1977, wintering numbers in France have been increasing; between 1980 and 2013, the wintering population grew by 49%, stabilizing between 2011 and 2013.<ref name="INPNCahierHabitatOiseaux5" />
Locally, there are marked differences between wintering sites. For example, along the English Channel coast, numbers have declined sharply by 80% since 1980, largely due to reduced habitat capacity and feeding areas at the Seine Bay, following the development of the Port of Le Havre.<ref name="avocetteseine2">Template:Cite journal</ref> In contrast, along the Atlantic coast, numbers increased by 107% since 1980. The Mediterranean wintering population has also risen by 200% since 1980, though this is tempered by strong interannual variations.<ref name="AtlasOiseauxFrance3" />
During the breeding season, the species is relatively localized, with 3,650 to 4,350 breeding pairs recorded in 2010–2011,<ref name="AtlasOiseauxFrance3" /> including 250 pairs along the English Channel and 1,500 to 2,500 pairs along the Atlantic coast in 2004.<ref name="INPNCahierHabitatOiseaux5" /> In the Mediterranean region, between 1991 and 1999, 810 to 928 pairs were recorded.<ref name="repromedit2">Template:Cite journal</ref> Between 1996 and 2011, the Mediterranean breeding population increased by over 50%, reaching approximately 1,500 pairs.<ref name="AtlasOiseauxFrance3" />
Along the Atlantic and English Channel coasts, the breeding population has significantly increased since the establishment of new colonies in the 1970s; since 1996, numbers have doubled, accounting for 57% of France's total breeding population.<ref name="AtlasOiseauxFrance3" /> In the Mediterranean, breeding numbers are generally stable, with notable variations by site (increases in Languedoc and a sharp decline in the Rhône Delta).<ref name="repromedit2" /> However, between 1997 and 2007, the Mediterranean population was considered to be declining on its wintering grounds and migratory routes.<ref name="AtlasOiseauxFrance3" />
Conservation status
Due to its extensive global range (over Template:Cvt) and large population size, the species is not considered threatened and has been classified as least concern (LC) by the IUCN since 2004.<ref name="UICN2" /> In Europe, its conservation status is deemed favorable.<ref name="INPNCahierHabitatOiseaux5" /> In France, it is also classified as least concern (LC) as both a breeding and wintering species. As a migratory species, it is classified as not applicable (NA) due to insufficient data.<ref>Template:Cite web</ref>
The species is considered vulnerable (VU) as a breeding species on the regional red list of Provence-Alpes-Côte d'Azur,<ref>Template:Cite journal</ref> near threatened (NT) on the red list of breeding birds in Languedoc-Roussillon, vulnerable (VU) in Poitou-Charentes, and least concern (LC) in Pays de la Loire. In Brittany, it is vulnerable (VU) as a breeding species and near threatened (NT) as a migrant. In Normandy, it is critically endangered (CR) as a breeding species and endangered (EN) as a wintering species. In Nord-Pas-de-Calais, it is vulnerable (VU) as a breeding species.<ref>Template:Cite journal</ref> In Belgium, specifically Wallonia, it is considered vulnerable (VU).<ref>Template:Cite journal</ref>
Threats

Various threats, mostly of anthropogenic origin, affect the Pied Avocet. The European population is relatively small and confined to a limited number of sites, particularly in winter.<ref name=":0">Template:Cite journal</ref> Many key wintering sites are located near oil port facilities, posing a significant petrochemical risk, as evidenced by a collision between two butane carrier ships in January 2006 in the Loire Estuary.<ref name="INPNCahierHabitatOiseaux5" /> The risk of oil spills, such as the ecological disaster caused by the Erika in 1999–2000, also led to a decline in French wintering populations.<ref name=":0" />
Climate change has a notable impact on the species' reproductive success and affects its coastal habitat.<ref name=":0" />
Habitat loss, particularly due to increasing coastal urbanization, is a major issue.<ref name="INPNCahierHabitatOiseaux5" /><ref name="avocettehyeres3" /> The degradation and destruction of coastal wetlands, essential for breeding, lead to more frequent disturbances, affecting reproduction, rest, and feeding by reducing available feeding areas for both chicks and wintering birds.<ref name="INPNCahierHabitatOiseaux5" />
Intensified agricultural practices have caused significant drying of marshes, with, for example, Template:Convert of wet meadows destroyed in the Marais Poitevin. Poor water management, with excessive water level fluctuations, can be disastrous for colonies, as seen in the Somme Bay.<ref name="INPNCahierHabitatOiseaux5" /> Additionally, the abandonment of traditional practices in salt marshes and exploited plots alters the species' characteristic habitat and associated vegetation, negatively impacting colonies.<ref name="avocettehyeres3" />
Specific urbanization examples include port developments, such as in France’s Seine Estuary<ref name="avocetteseine2" /> and Loire Estuary, where mudflat areas have decreased by 25% in just 20 years. Excessive urbanization in Portugal and the Yellow Sea also poses problems.<ref name="delhoyo3">Template:Cite book</ref> The species may also be affected by reduced river flows in certain areas, such as in China.
Pollution is harmful to the Pied Avocet, with pollutants such as PCBs, insecticides, lead, mercury, and selenium found in eggs and bird tissues in Europe.<ref name="delhoyo3" />
Locally, hunting and mosquito control can disturb the species and disrupt or destroy favorable biotopes.<ref name="avocettehyeres3" /> The species is susceptible to diseases such as avian botulism and avian influenza.<ref>Template:Cite journal</ref>
Finally, the species may occasionally be affected by egg collection for private collections.<ref>Template:Cite journal</ref>
Conservation measures

The species is protected in France under the Nature Protection Law of July 10, 1976, and its implementing decrees. The European Commission’s 1979 Birds Directive and the 1979 Bern Convention on European wildlife ensure full legal protection, prohibiting disturbance of birds and their nests.<ref name="avocettehyeres3" /><ref name="INPNCahierHabitatOiseaux5" /> The species is listed in Annex I of the Birds Directive, Annex II of the Bern Convention, Annex II of the Bonn Convention, and Category B1 of the African-Eurasian Migratory Waterbird Agreement (AEWA).<ref name="avocettehyeres3" /><ref name="INPNCahierHabitatOiseaux5" />
The establishment of nature reserves, marine reserves, and special protection areas (SPAs) has benefited the Western European population during the 20th century.<ref name="INPNCahierHabitatOiseaux5" /><ref name=":0" />
Various management measures can promote settlement and reproduction. Constructing artificial nesting sites in coastal areas, such as pebble beaches or islands and rafts with sparse vegetation, can attract breeding pairs.<ref>Template:Cite journal</ref> Increased breeding pairs have also been noted with the introduction of livestock grazing in coastal meadows near breeding sites, reducing vegetation cover and improving visibility and predator detection.<ref>Template:Cite journal</ref>
Numerous color-banding programs, using metal and colored rings, exist in Europe, enhancing ornithologists’ understanding of the species’ ecology and migratory movements, as well as improving monitoring of breeding behavior and site management.<ref name="avocettehyeres3" /><ref>Template:Cite web</ref>
Gallery
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Adult feeding
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Adult in flight
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ID composite
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Video showing bird seeking food
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Pied avocets in Little Runn of Kutch, India
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Unlike other waders, the pied avocet has webbed feet, and can swim well.