Phoenicopteriformes

Flamingos

(Phoenicopteridae)

Class Aves

Order Phoenicopteriformes

Family Phoenicopteridae

Number of families 1

Thumbnail description
Large, very long-legged and long-necked waterbirds with specialized down-curved, filter-feeding bills, and pink, black, and white plumage

Size
31.5–63 in (80–160 cm); 5.5–7.7 lb (2.5–3.5 kg)

Number of genera, species
3 genera; 5 species

Habitat
Shallow saline, brackish, and alkaline waters

Conservation status
Near Threatened: 2 species

Distribution
South America including Galápagos, the Caribbean, Africa, southern Europe, southwest Asia, the Middle East, Indian subcontinent

Evolution and systematics

The taxonomic status of flamingos continues to be the subject of much debate. Current placement in a separate order between storks and herons (Ciconiiformes) and wildfowl (duck, geese, and swans; Anseriformes) has been followed most often and, despite recent challenges, still seems to be the most suitable. Certain skeletal features and courtship displays are similar to those of storks, while egg-white proteins show similarities with herons. There are several characteristics shared with wildfowl, including bill structure, webbed feet, voice, other courtship displays, chick behavior patterns, and external parasites. Flamingos are set apart from these families by, for example, the existence of communal displays, an absence of territorial behavior, and creching of young.

A study of muscle and bone structure, eggs, and internal parasites has suggested an evolutionary origin from longlegged wading birds (Charadriiformes), e.g., stilts and avocets. However, DNA-DNA hybridization techniques suggest a closer kinship with not just storks, but pelicans and New World vultures. Work using bile-gland acids puts flamingos firmly into the Anseriformes.

Primitive flamingos exist as fossils from c. 50 million years ago (Middle Eocene); fossils from the Oligocene period (about 30 million years old) appear identical with present-day genera. Flamingos were then more widespread than they are today, occurring in both North America and Australia, whence they are now absent, as well as over a much larger area of Europe. Their range then as now would have been linked to availability of shallow wetlands in a warm-temperate to tropical climate and their fossils therefore suggest the extent of such habitats in the past.

The separation of flamingos into three genera and five species, plus one sub-species, is based on relatively minor differences. The greater (Phoenicopterus ruber) and Chilean (Phoenicopterus chilensis) flamingos are placed in one genus, the former with two subspecies. The other three species, Lesser (Phoeniconaias minor), Andean (Phoenicoparrus andinus), and James' (Phoenicoparrus jamesi) flamingos are placed in two further genera, the difference between them being the presence of a hind toe in the lesser flamingo.

Physical characteristics

Flamingos are unmistakable in size, shape, and coloring, made more so by their habit of flocking, sometimes in exceptional numbers, e.g. gatherings of lesser flamingos in excess of one million birds. All five species are similar in shape and have common plumage features. They are separable in the field by size and the coloring of plumage and soft parts. The body is oval, with exceptionally long legs and a long neck. The relatively small size of the head is emphasized by the

large bill, which is sharply decurved in the middle. Very unusual among birds, the upper bill is smaller than the lower. Both are lined with lamellae for filter-feeding, as is the large, fleshy tongue. The extremely long, spindly legs are an adaptation for wading, and the three front toes are webbed, supporting the birds on mud and allowing them to swim.

The largest of the flamingos, the greater, stands up to 60 in (150 cm) tall; the smallest, the lesser, stands about 35 in (90 cm). The dominant colors are pink and crimson-red. These colors are vital to their display, contrasting with black flight-feathers. The bill and legs are brightly colored, too, in red, pink, and yellow. Sexes are similar in plumage, but the male is slightly larger than the female. Small young are covered in whitish-grayish down, and their first set of feathers is gray-brown. At about one year old, they molt into a very pale version of adult plumage, acquiring full breeding coloring at three to four years. They breed for the first time from about four years old.

Distribution

Flamingos are found in South America, including the Galápagos Islands; in the Caribbean; and throughout much of Africa, including the north and west coasts, the full length of the Rift Valley in East Africa, and in South Africa. In Europe, they are confined to the extreme south, around the Mediterranean; and are found in Turkey and east into southwest Asia, and from the Middle East to Pakistan, India, and Sri Lanka.

Three species, the Chilean, Andean, and James', occur only in South America, the Chilean having the largest range, from central Peru through Chile, Bolivia, and Argentina south to Tierra del Fuego. The Andean and the James' Flamingos are confined to much the same area of the high Andes, encompassing southern Peru, western Bolivia, northern Chile, and northwestern Argentina. The lesser flamingo has a large range in East and South Africa, with much smaller numbers occurring in West Africa, and in Pakistan and India.

The most widespread species is the greater flamingo, of which one subspecies (Phoenicopterus ruber ruber) breeds on the Galápagos; on several Caribbean islands, including the Bahamas, Cuba, and the Netherlands Antilles; and on the coasts of northern South America and eastern Mexico. The nominate subspecies (Phoenicopterus ruber roseus) has a very extensive, if scattered, range in West, East, and South Africa; on the northern and southern coasts of the Mediterranean; in the Middle East; southwest Asia; and Pakistan, India, and Sri Lanka.

There is little information on historical ranges, but the greater flamingo formerly bred in Kuwait, Egypt, Algeria, and the Cape Verde Islands.

Habitat

Flamingos are specialized feeders requiring a very specialized habitat, consisting of shallow lakes and lagoons, which can be inland or coastal, including tidal, and ranging from strongly saline (up to twice or even more the salinity of sea-water) to strongly alkaline (with a pH in excess of 10). While quite small waterbodies, including artificial saltpans, may be used for feeding, breeding normally takes place on much larger waters, including lakes in East Africa up to hundreds of square miles in extent. In southern France, the greater flamingo also feeds in fresh water, on rice-paddies, but this is a relatively new habit and probably related to the greatly increased numbers in the area.

The waterbodies used by flamingos extend from sea-level to nearly 14,000 ft (3,500 m) in the Andes. At these altitudes, the birds are able to live throughout the year in the presence of hot springs that keep the water from freezing. The birds' tolerance to conditions shared by only a handful of other organisms, e.g., aquatic invertebrates, diatoms, and algae, all of which they feed on, is astonishing. They can cope not only with water temperatures of up to 155°F (68°C), but with the extremely caustic nature of the water, containing chlorides and sulfates often in very high concentrations. Their adaptation to living in such conditions has allowed them to exploit an abundant food supply in the absence of any competitors. That the absence of food competitors is important has been demonstrated for the Chilean flamingo, which lives almost exclusively on lakes without indigenous fish and avoids those with them.

Behavior

The main collective display of flamingos starts well before the breeding season and consists of ritualized stretching and preening movements, including self-explanatory "head-flagging"; the "wing-salute," when the wings are briefly opened to expose their bright colors; and "marching," when the entire tightly packed group of birds walks rapidly in one direction before abruptly turning about and walking back again.

Vocalizations form an important part of the ritualized displays. Loud honking calls are given during head-flagging and lower-pitched grunts during the wing-salute. The voice is important for keeping flocks together, particularly during movements, and for communication between the breeding pair and their chick.

While all five species of flamingo indulge in some movements, many of these are adaptations to changes in their habitat, rather than true seasonal migrations. The more northerly European and Asian populations of the greater flamingo make regular southerly movements in autumn, returning in spring. However, the movements of both greater and lesser flamingos over their extensive ranges in Africa are dictated by irregular patterns of drought and rainfall and associated water-level changes, which in turn affect both the food supply and availability of suitable nesting areas. Chilean flamingos breeding in the high Andes descend to the coast for the winter, but such vertical movements are rare among both the Andean and James' flamingos. The population of greater flamingos in the Galápagos is sedentary, as are at least some of those in the Caribbean.

Feeding ecology and diet

Flamingos have three main foods: algae; diatoms; and small aquatic invertebrates, including, in different areas, brine-shrimp, brine-flies, and snails. The greater and Chilean flamingos are generalist feeders, taking a wide variety of available invertebrates, some seeds, algae, and diatoms. The other three species are specialists, lesser flamingos feeding exclusively on blue-green algae, while the Andean and James' flamingos take mainly diatoms.

Bills have broad areas of filtering lamellae. The smaller upper portion of the bill fits onto the larger lower one like a lid. A sharp angle about the middle of the bill ensures that, when the flamingo lowers its head into the water to sieve for food, the upper portion of the bill faces downward with the bill upside down. It also means that the lamellae-lined cleft between the upper and lower portions remains small along its entire length when the bill is open.

This mechanism permits particles only up to a certain maximum size to be sucked into the beak with the water. The bird creates suction by retracting its thick fleshy tongue with the beak slightly opened, reducing the pressure in the bill and causing water to enter. Closing the bill and moving the tongue forward, expels the water leaving the food particles caught on the lamellae (thin flat membranes). At the next retraction of the tongue, these food particles are carried into the oral cavity by the bristle-like projections of the tongue, and simultaneously water once more enters the bill.

The differences among species in their major foods causes species with the finer lamellae to sift just beneath the water surface, while species with the coarser weave largely work in the mud beneath the water. This makes it possible for multiple flamingo species to live in the same area and even to feed in the same lake without competing. Thus ranges of the greater and lesser flamingos and of the Chilean, Andean, and James' flamingos, overlap. Species with similar filtration apparatus, and hence similar food, always have separate areas of distribution.

Reproductive biology

Flamingos are among the most gregarious of birds, feeding and breeding in flocks and colonies that may contain more than a million individuals. However, even though they live in these huge assemblies, the birds are monogamous and probably pair for life. The social stimulation of group displays, which can involve hundreds or thousands of birds, is a vital factor in initiating breeding attempts and bringing them into close synchronization.

Pair formation displays are similar to the group displays already described, but take place slightly apart from the large flocks, as does copulation. Actual nest sites within the colony site are selected by the female shortly before egg-laying, and she commences nest construction, though both birds will complete it. The nest is a truncated cone of heaped mud, with a shallow depression in the top for the single elongated, chalky white egg. Nest-building continues for several days after egglaying, the birds using available materials, including mud, stones, shells, etc., within their reach while standing or sitting on the nest site, piling them up around themselves. The height of the mud cone varies according to the nature of the

ground; it may be up to 16 in (40 cm) high or be altogether absent on rocky ground.

Incubation is by both parents and lasts 27–31 days. The newly hatched chick has a white, downy plumage; a straight, red bill; and thick, red legs, which become black after 7–10 days. The chick leaves the nest when it is 4–7 days old and is, to start with, accompanied by the parents and defended against other birds that come too close. Soon after this, the parents leave the chick alone for longer and longer periods, and it joins others to form loose groups, or creches. At about 2–3 weeks, the chick grows a second gray, downy plumage, and the bill begins to bend. At about 4 weeks, the first contour feathers appear on the shoulders.

The bill lamellae are not yet fully functional in 70-day-old young, which can already fly. Up to this age, young depend largely on a highly nutritious liquid secreted by the parents in the region of the esophagus and proventriculus. This secretion has a nutritional value comparable to that of milk; its content of carotenoids and blood give it a bright red color and are the same pigments synthesized by the parents to color their feathers. Parents know their own young by their voices and will feed no others, even when the young are gathered in groups.

The breeding season of flamingos in tropical and subtropical areas is dictated mainly by rainfall providing suitable shallows and food abundance, and therefore may take place at any time of the year, or not at all, for several years in succession. In temperate areas, such as southern Europe, breeding occurs mainly in spring, but an attempt may be abandoned if conditions become too dry, or the birds may miss a year altogether. This irregularity extends to the colony sites chosen. These sites may be used several years in succession, or the birds may shift to a new site almost every year.

Conservation status

The Andean and James' flamingos are both classified as Near Threatened, having been changed from Threatened in recent years, as a result of better information. Both are thought to have populations of up to 50,000 birds, but both are concentrated on relatively few waterbodies where some habitat destruction through pollution, mining, and diversions of streams has taken place. Increasing access through road construction has also led to increased egg-harvesting by humans and colony disruption by foxes. However, the creation of reserves should provide some relief from these problems.

The Chilean flamingo is thought to number around 200,000 birds, and despite some habitat loss and egg-harvesting, it probably has a favorable conservation status, as have both the greater and lesser flamingos. The former has populations of about 400–500 in the Galápagos, up to 90,000 in the Caribbean. and perhaps 800,000 in its European-African-Asian range. Numbers in the Caribbean have declined sharply in recent years, through habitat destruction by drainage and reclamation, but have increased strongly in southwest Europe, as a result of conservation measures on its principal breeding localities in France and Spain. The lesser flamingo is the most numerous and certainly numbers 3–4 million birds, perhaps as many as 6 million.

Significance to humans

The flamingo was known to Neolithic man, who illustrated it around 5000 b.c. in cave paintings in southern Spain. Egyptians used the flamingo as one of their hieroglyphic symbols to indicate the color red. They also regarded it as a living embodiment of the sun god Ra, and there may also have been a link with the mythical Phoenix.

Flamingos have long been eaten, with the Romans regarding the tongue as a special delicacy. Hunting of flamingos has always been constrained by the remote and difficult terrain in which so many of them live and by the extreme water conditions where they breed, though this hasn't stopped some native peoples from regular egg-harvesting, which has probably existed for many centuries.

The only known instance of flamingos becoming pests has been in the Camargue region of southern France where birds from this increasing population started to feed in newly sown rice paddies in the vicinity, taking the rice grains as food. The problem has been solved largely by systematic scaring during the critical period before the rice sprouts.

Species accounts

List of Species

Greater flamingo

Phoenicopterus ruber

taxonomy

Phoenicopterus ruber Linnaeus, 1758, Bahamas. Two subspecies: P.r. ruber and P.r. roseus.

other common names

English: Caribbean, West Indian flamingo, rosy flamingo; French: Flamant rose; German Rosaflamingo; Spanish: Flamenco Común.

physical characteristics

47–57 in (120–145 cm) 4.6–9.0 lb (2.1–3.4 kg); female approximately 10–20% smaller than male. Largest of the flamingos, adults are rosy red (Caribbean population) or whitish tinged with pink (European-African-Asian population) with brighter pink on the wings. The flight feathers are black. The bill is pink with a black tip, and legs are pink with darker pink joints. Hatchling is dark or light gray down with bright red legs and straight red bill. Juvenile is gray-brown, acquiring pale pink upper wing panel and pink tinge to gray legs and bill at 11 months; at four years, body plumage and lower portion of bill still grayer than adults.

distribution

P. r. ruber: Galápagos and Caribbean; P. r. roseus: North, West, East, and South Africa, southern Europe, Middle East, southwest Asia and Pakistan, India, and Sri Lanka.

habitat

Shallow saline and alkaline lakes and lagoons.

behavior

Gregarious, with group displays involving ritualized movements of head and wings, accompanied by loud calls. In flocks of a few hundred to over one million.

feeding ecology and diet

Sieves aquatic invertebrates, seeds, algae, and diatoms from shallow water and mud.

reproductive biology

Lays single egg (large, elongated, white, and chalky with reddish yolk) on mud nest close to or in shallow water, the time of breeding being dictated by rainfall rather than seasons. Nests in dense colonies, up to tens or hundreds of thousands of pairs. Incubation period 27–31 days; fledging 65–90 days. Both parents incubate and care for young, which gather into groups. Productivity very variable, with complete failures in some years. Age of first breeding normally five or six years.

conservation status

Not threatened. Has declined in the Caribbean but increased in southwestern Europe. Elsewhere, very numerous, though subject to wide fluctuations in numbers based on rains and breeding success.

significance to humans

Sometimes hunted for food or sport, e.g., in Egypt.

Chilean flamingo

Phoenicopterus chilensis

taxonomy

Phoenicopterus chilensis Molina, 1782, Chile.

other common names

French: Flamant du Chili; German: Chileflamingo; Spanish: Flamenco Chileno.

physical characteristics

38–42 in (96–107 cm); c. 5.0 lb (2.3 kg); female approximately 10% smaller than male. Smaller than the greater flamingo, with overall coloring similar to that of the European-African-Asian population, though pinker on the neck and breast. The inner third of the bill is pink, the remainder black, while legs are pink with darker pink joints. Chicks covered in gray down when born; may retain gray markings, at least in part, or develop white plumage that remains until two to three years of age. The juvenile is gray-brown.

distribution

Central Peru south through Chile, Bolivia, and Argentina to Tierra del Fuego.

habitat

Shallow saline and alkaline lakes and lagoons.

behavior

Gregarious, with group displays involving ritualized movements of head and wings, accompanied by loud calls. In flocks of a few hundred to tens of thousands.

feeding ecology and diet

Sieves aquatic invertebrates, seeds, algae, and diatoms from shallow water and mud.

reproductive biology

Lays single egg (chakly-white, goose-sized) on mud nest close to or in shallow water, the time of breeding being dictated by rainfall rather than seasons. Nests in dense colonies, up to several thousands of pairs. Incubation period 27–31 days; fledging 70–80 days. Both parents incubate and care for young, which gather into groups. Productivity very variable, with complete failures in some years.

conservation status

Not threatened. Egg-harvesting and habitat destruction have caused declines at some colonies, but overall status probably stable.

significance to humans

Egg-harvesting and perhaps some hunting.

Lesser flamingo

Phoeniconaias minor

taxonomy

Phoeniconaias minor Geoffroy, 1798, no locality = Senegal.

other common names

French: Flamant nain; German: Zwergflamingo; Spanish: Flamenco Enano.

physical characteristics

31–35 in (80–90 cm); 3.3–4.4 lb (1.5–2.0 kg); female approximately 10% smaller than male. Smallest of the flamingos, the adults are similar to the greater flamingo of the European-African-Asian population but with a proportionately longer

bill, which is much darker red, paler toward the tip, which is black. Legs are dark pink. Hatchling has bright coral-red legs and straight reddish pink bill. Juvenile is gray-brown.

distribution

East and South Africa, with small numbers in West Africa and in Pakistan and India.

habitat

Shallow saline and alkaline lakes and lagoons.

behavior

Gregarious, with group displays involving ritualized movements of head and wings, accompanied by loud calls. In flocks of a few hundred to over one million.

feeding ecology and diet

Sieves blue-green algae from shallow water and mud.

reproductive biology

Lays single egg (chalky-white, elongated; large but slightly smaller than P. ruber) on mud nest close to or in shallow water, the time of breeding being dictated by rainfall rather than seasons. Nests in dense colonies, up to hundreds of thousands of pairs. Incubation period 28 days; fledging 70–75 days. Both parents incubate and care for young, which gather into groups. Productivity very variable, with complete failures in some years. Age of first breeding normally three or four years.

conservation status

Not threatened. Although numbers show huge fluctuations at individual sites, overall numbers believed more or less stable.

significance to humans

None known.

Andean flamingo

Phoenicoparrus andinus

taxonomy

Phoenicoparrus andinus Philippi, 1854, salt lake near Altos de Pingopingo, Antifagasta, Chile.

other common names

English: Greater Andean flamingo; French: Flamant des Andes; German: Andenflamingo; Spanish: Parina Grande.

physical characteristics

40–43 in (102–110 cm); 4.4–5.3 lb (2.0–2.4 kg); female approximately 10% smaller than male. The head and neck are suffused with wine-red, the rest of the body whitish, tinged with pink, brightest on the wings. The flight feathers are black. The inner third of the bill is yellow, with a reddish patch between the nostrils, the remainder black. Legs and feet are yellow. The juvenile is grayish, streaked darker.

distribution

Found only in the high Andes of southern Peru, Bolivia, northern Chile, and northwestern Argentina.

habitat

Shallow high-altitude saline and alkaline lakes and lagoons.

behavior

Gregarious, with group displays involving ritualized movements of head and wings, accompanied by loud calls. In flocks of a few hundred to several thousand.

feeding ecology and diet

Sieves diatoms from shallow water and mud.

reproductive biology

Lays single egg on mud nest close to or in shallow water, the time of breeding being dictated by rainfall rather than seasons. Nests in dense colonies, up to several thousands of pairs. Incubation period c. 28 days; fledging probably 70–80 days. Both parents incubate and care for young, which gather into groups. Productivity very variable, with complete failures in some years. Age of first breeding probably four or five years.

conservation status

Not threatened, but has declined in some areas in recent years through habitat destruction and egg-harvesting. Recent establishment of reserves should benefit the species.

significance to humans

Egg-harvesting.

James' flamingo

Phoenicoparrus jamesi

taxonomy

Phoenicoparrus jamesi P.L. Sclater, 1886, Sitani, at foot of Isluga volcano, Tarapacá, Chile.

other common names

English: Lesser Andean flamingo, Puna flamingo; French: Flamant de James; German: Jamesflamingo; Spanish: Parina Chica.

physical characteristics

35–26 in (90–92 cm); c. 4.4 lb (2.0 kg); female approximately 10% smaller than male. Adults are overall whitish, tinged with

pink, with a band of carmine streaks across the breast; bright red on the wings. Flight feathers are black. Bill is yellow, with red at the base and a broad black tip. Legs and feet are pink. The juvenile is brownish, streaked darker.

distribution

Found only in the high Andes of the extreme south of western Bolivia, northern Chile, and northwestern Argentina.

habitat

Shallow high-altitude saline and alkaline lakes and lagoons.

behavior

Gregarious, with group displays involving ritualized movements of head and wings, accompanied by loud calls. In flocks of a few hundred to several thousand.

feeding ecology and diet

Sieves diatoms from shallow water and mud.

reproductive biology

Lays single egg on mud nest close to or in shallow water, the time of breeding being dictated by rainfall rather than seasons. Nests in dense colonies, up to a few thousands of pairs. Incubation period probably c. 28 days; fledging probably 70–80 days. Both parents incubate and care for young, which gather into groups. Productivity very variable, with complete failures in some years. Age of first breeding probably four or five years.

conservation status

Has declined in some areas in recent years, through habitat destruction and egg-harvesting. Recent establishment of reserves should benefit the species.

significance to humans

Egg-harvesting.

Resources

Books

Cramp, S., and K.E.L. Simmons, eds. Vol. 1 of The Birds of the Western Palearctic. New York: Oxford University Press, 1977.

del Hoyo, J., A. Elliot, and J. Sargatal, eds. Handbook of the Birds of the World. Vol. 1, Ostrich to Ducks Barcelona: Lynx Edicions, 1992.

Kear, J., and N. Duplaix-Hall, eds. Flamingos. Berkhamsted, United Kingdom: Poyser, 1975.

Ogilvie, M., and C. Ogilvie. Flamingos. Gloucester, England: Alan Sutton Publishing Ltd., 1986.

Periodicals

Johnson, A.A. "Greater Flamingo." BWP Update 1 (1997): 15–24.

Olson, S.L., and A. Feduccia. "Relationships and evolution of Flamingos (Aves: Phoenicopteridae)." Smithsonian Contributions to Zoology No. 316 (1980).

Sibley, C.G., K.W. Corbin, and J.H. Haavie. "The relationships of the Flamingos as indicated by the egg-white proteins and hemoglobins." The Condor 71 (1969): 155–179.

Organizations

Wetlands International/Survival Service Commission Flamingo Specialist Group. c/o Station Biologique de la Tour du Valat, Le Sambuc, Arles 13200 France.

Other

Chilean Flamingos Page. Decatur (Illinois) Public Schools. 6 Dec. 2001. <http://www.dps61.org/jh/ZooWeb/Flame/webpage.htm>.

Chilean Flamino Page. Rolling Hills Refuge Wildlife Conservation Center, Salina, Kansas. 6 Dec. 2001. <http://www.rhrwildlife.com/theanimals/f/flamingochilean>.

Flamingo, Chilean Page. Phoenix Zoo. 6 Dec. 2001 <http://www.phoenixzoo.org/zoo/animals/facts/flamchil.asp>.

The Roberts VII Project. Draft species texts. Greater Flamingo 6 Dec. 2001 <http://www.uct.ac.za/depts/fitzpatrick/docs/r096.html>. Lesser Flamingo 6 Dec. 2001 <http://www.uct.ac.za/depts/fitzpatrick/docs/r097.html>.

Malcolm Ogilvie, PhD