The crab-plover or crab plover (''Dromas ardeola)'' is a coastal

wader 245px, A flock of Red_knot.html" ;"title="Dunlins and Red knot">Dunlins and Red knots Waders or shorebirds are birds of the order Charadriiformes commonly found wikt:wade#Etymology 1, wading along shorelines and mudflats in order to foraging, ...

(shorebird). It is the only member of the genus ''Dromas'' and the family Dromadidae. It is unique among

s in making use of ground warmth to aid the incubation of its eggs. The crab-plover is classified in the suborder Lari, making it more closely related to gulls and

auk Auks or alcids are birds of the family Alcidae in the order Charadriiformes. The alcid family includes the Uria, murres, guillemots, Aethia, auklets, puffins, and Brachyramphus, murrelets. The family contains 25 extant or recently extinct speci ...

s than to most other waders such as

plover Plovers ( , ) are members of a widely distributed group of wader, wading birds of subfamily Charadriinae. The term "plover" applies to all the members of the subfamily, though only about half of them include it in their name. Species lis ...

s (suborder

Charadrii FIle:Vadare - Ystad-2021.jpg, 245px, A flock of Dunlins and Red knots Waders or shorebirds are birds of the order Charadriiformes commonly found wikt:wade#Etymology 1, wading along shorelines and mudflats in order to foraging, forage for food c ...

) and sandpipers (suborder Scolopaci).

Description

This bird resembles a

, but has very long grey legs and a strong heavy black bill similar to a tern. Its black-and-white plumage and long-necked upright posture with heavy bill makes it distinctive and unmistakable. Its bill is unique among waders, and specialised for eating crabs. It has partially webbed toes. The plumage is white except for black on its back and in the primary feathers of the wings. They are noisy birds, calling frequently on their breeding sites and in their wintering grounds. The usual call is a ''ka'' similar to that of the bar-tailed godwit but repeated rapidly. Flocks may produce a whinnying sound that rises and at in the breeding season produce whistling ''kew-ki-ki'' notes. Males and females are not easily distinguished but males have a heavier and longer bill. Juveniles have the black on the mantle, greyish and remain in this plumage for a year. Flocks fly in lines or "V" formations. The crab-plover is one of the species to which the ''Agreement on the Conservation of African-Eurasian Migratory Waterbirds'' ( AEWA) applies.

Range

It is resident on the coasts and islands of the

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or approximately 20% of the water area of Earth#Surface, Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia (continent), ...

, where it feeds on

crab Crabs are decapod crustaceans of the infraorder Brachyura (meaning "short tailed" in Greek language, Greek), which typically have a very short projecting tail-like abdomen#Arthropoda, abdomen, usually hidden entirely under the Thorax (arthropo ...

s and other small animals. They are gregarious and will feed in large groups, at night and during dawn and dusk as well as during the day; this

crepuscular In zoology, a crepuscular animal is one that is active primarily during the twilight period, being matutinal (active during dawn), vespertine (biology), vespertine/vespertinal (active during dusk), or both. This is distinguished from diurnalit ...

and

nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ...

behaviour is more common during the breeding season. They breed around the

Arabian Sea The Arabian Sea () is a region of sea in the northern Indian Ocean, bounded on the west by the Arabian Peninsula, Gulf of Aden and Guardafui Channel, on the northwest by Gulf of Oman and Iran, on the north by Pakistan, on the east by India, and ...

, Gulf of Oman and the

Persian Gulf The Persian Gulf, sometimes called the Arabian Gulf, is a Mediterranean seas, mediterranean sea in West Asia. The body of water is an extension of the Arabian Sea and the larger Indian Ocean located between Iran and the Arabian Peninsula.Un ...

Red Sea The Red Sea is a sea inlet of the Indian Ocean, lying between Africa and Asia. Its connection to the ocean is in the south, through the Bab-el-Mandeb Strait and the Gulf of Aden. To its north lie the Sinai Peninsula, the Gulf of Aqaba, and th ...

and

Somalia Somalia, officially the Federal Republic of Somalia, is the easternmost country in continental Africa. The country is located in the Horn of Africa and is bordered by Ethiopia to the west, Djibouti to the northwest, Kenya to the southwest, th ...

in the months of April to July then disperse across the Indian Ocean in August as far as the Andaman Islands and

Sri Lanka Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka, also known historically as Ceylon, is an island country in South Asia. It lies in the Indian Ocean, southwest of the Bay of Bengal, separated from the Indian subcontinent, ...

in the east and

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

and

Madagascar Madagascar, officially the Republic of Madagascar, is an island country that includes the island of Madagascar and numerous smaller peripheral islands. Lying off the southeastern coast of Africa, it is the world's List of islands by area, f ...

Habits

The crab-plover is unusual for waders in that it nests in

burrow file:Chipmunk-burrow (exits).jpg, An eastern chipmunk at the entrance of its burrow A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of Animal lo ...

s in sandy banks. In the Red Sea region, the breeding season begins around the middle of May. It is a colonial breeder, nesting in colonies as large 1500 pairs. It lays one white egg, occasionally two, which are large for its body size. The nest burrow temperature is optimal due to solar radiation and the parents are able to leave the nest unattended for as long as 58 hours. The chicks are also unique for the usually nidifugous waders in being unable to walk and remain in the nest for several days after hatching, having food brought to them. Even once they

fledge Fledging is the stage in a flying animal's life between egg, hatching or birth and becoming capable of flight. This term is most frequently applied to birds, but is also used for bats. For altricial birds, those that spend more time in vulnera ...

they have a long period of parental care afterwards. Both males and females take care of the young.

Notes

References

*Handbook of the Birds of the World, Volume Three, Hoatzin to Auks; ''de Hoyo, Elliot'' and ''Sargatal'',

External links

Crab Plover videos, photos & sounds
on the Internet Bird Collection {{Taxonbar, from=Q213836 Lari Birds of the Middle East Birds of East Africa Birds of the Arabian Peninsula Birds described in 1805 Taxa named by Gustaf von Paykull