SPECIES

Greater Flamingo Phoenicopterus roseus Scientific name definitions

Alfredo Salvador, Miguel Á. Rendón, Juan A. Amat, and Manuel Rendón-Martos
Version: 2.0 — Published August 12, 2022

Diet and Foraging

Introduction

Greater Flamingo generally feeds in shallow water. It is a specialized filter feeder that uses a variety of feeding methods and can show plastic foraging behavior depending on food availability and feeding microhabitats. It is also considered an ecosystem engineer that can modify aquatic habitats through its foraging activity. The diet is varied and consists of small invertebrates, microalgae, and plant seeds.

Feeding

Main Foods Taken

The diet consists of crustaceans, mollusks, aquatic insects, annelids, microalgae, and plant seeds (32, 4). Chicks are fed exclusively from secretions produced by their parents for three months until they are able to feed themselves (10). See Parental Care.

Microhabitats for Foraging

There is little information on feeding microhabitats for Greater Flamingo. It usually forages in water 5–50 cm deep, more rarely 90 cm deep (10). In the Camargue (France), dye-marked breeding birds were observed foraging in all kinds of habitats, from freshwater to hypersaline wetlands (10). In Abijata-Shalla Lakes National Park (Ethiopia), it was observed mostly in offshore areas (60%); it also foraged in water just along the shoreline (33%) and on mudflats (7%) (131). At Lake Elmenteita (Kenya), young birds foraged closer to the shore than adults (33). At Lake Nakuru (Kenya), it was mainly observed off the mouths of streams or near springs (33).

Habitat selection during the breeding season depends largely on resource availability. In the Camargue, it used different complexes of wetlands over the course of the chick-rearing period (155), with saltworks and freshwater marshes being the main habitats used in the early season, and saline wetlands later. Using stable isotopes, it was found that breeding adults used saltworks (38%) and freshwater marshes (33%) during the early phases of chick care, while the use of saline wetlands increased later in the season (54%) (155). These differences use were likely related to changes in habitat availability throughout the season, as well as to differences in competitive ability between adults (155). Stable isotope signatures in feathers also suggested that chicks fed from temporary marshes in the Camargue attained higher body condition than those fed from permanent marshes (155).

A similar pattern of habitat use was also found using stable isotopes for birds breeding in Fuente de Piedra Lake (Spain). In this case, the adults mainly foraged in the marshes of the Guadalquivir, located >120 km from the breeding lake (see Parental Care). There, the flamingos used the natural temporary marsh during the early phases of chick rearing, while the use of an artificial wetland (a fish farm) was more important in the later stages of chick rearing (156). The use of natural temporary marshes was also more important in wetter years than in drier years (156).

Food Capture and Consumption

Bill Structure

The bill is curved ca. 50º ventrally in the middle (48, 157). A small keeled maxilla fits closely along a large, deep, trough-like lower jaw. The trough-like mandible houses a thick and fleshy tongue. The distal part of the maxilla is straight and flattened dorsoventrally. The lateral wall of the mandible is covered with hard keratin, but the skin becomes flexible at the distal end of the bill curvature.

The upper bill carries inner and outer plates of keratin lamellae (157). The outer lamellae include both large marginal and small sub-marginal hook-like lamellae that gradually become finer from the distal to proximal end of the bill; the inner lamellae appear as transverse rows of small bladed lamellae directed inwards and backwards. The serrated mandibular, marginal, blade-like lamellae oppose the outer maxillary marginal lamellae. The juxtaposition of large marginal and smaller sub-marginal maxillary lamellae, together with the marginal mandibular lamellae determines the functional mesh sizes in Greater Flamingo (48, 157). When the bill is closed, a slit of 2 mm is left between the bill edges. However, the functional mesh size varies along the length of the bill, with a mesh size of 1.6 mm (height) x 1.7 mm (width) at the distal portion and 2.0 mm (height) x 0.7 mm (width) at the curved portion of the bill. In an experimental study with oval-like seeds (157), the accuracy of both excluding and filtering was established at about 0.5–1.0 mm, but discrimination capacity decreased outside sizes within the range 1.5–4.0 mm.

The tongue, when protracted, fills the mouth with the bill closed (48, 157). A bilateral series of about 20 flexible spines (3–5 mm) that point dorsally lie on the proximal part of the tongue. Two parallel series of spines pointing caudally are also present at the base of the tongue, marking the entrance into the oropharynx.

Foraging

When foraging, Greater Flamingo most commonly uses filter feeding, which comprises four phases (157): searching, filtering, transporting, and swallowing. During feeding, it turns its head so that the lower bill is above the upper bill, and the straight distal portion is submerged and held horizontally relative to the substrate. It opens its bill to a narrow gape, and then cyclic motions of the bill, tongue, and head determine the inflow and outflow of water to filter food. Filtering and transporting cycles are simultaneous, with the lingual spines transporting the filtered food into the pharynx.

As it filters food from the water column, it will use a variety of behaviors and motions as it forages. The most common foraging behavior is to slowly walk forward and filter the water column or grab prey with the tip of the bill. In sites up to 105 cm deep, it swims and upends to reach the lower layers of water (33, 10). Birds may also feed by just skimming the surface of the water, moving the bill side to side while swimming or walking.

In soft substrates, Greater Flamingo will employ a stamping or pit foraging behavior. In this method, the flamingo turns in a circle around their bill, creating a pit 63–96 cm diameter (mean 80 cm, n = 119) (10). A study conducted in the Camargue (France) showed that stamping was a lateralized behavior, such that individuals preferentially turned one direction or the other when foraging. During pit foraging, 63.6% of individuals turned counterclockwise (n = 77), making the first step forward with the right leg. The functional significance of preferentially turning counterclockwise during stamping is unknown (158).

Another foraging method involves stamping and lifting legs in rapid succession while holding the bill underwater near the substrate; birds remain in one place when foraging in this way, and do not turn in a circle. During channel foraging, a bird will walk slowly with its head immersed and the bill creating a channel in the mud 1 cm deep and 2–3 m long (10). Birds have also occasionally been observed with their necks outstretched in the direction of a visually detected prey to capture it with their beaks (159).

The foraging strategy used by an individual is variable and seems dependent on prey and habitat conditions. In Langebaan Lagoon (South Africa), channel foraging was linked to the abundance of surface fauna and pit foraging increased with higher concentrations of benthic microalgae (160). In Fuente de Piedra Lake (Spain), stamp feeding behavior increased when food abundance (crustacean zooplankton) decreased and when the wind concentrated prey on the shore of the lake (117).

Greater Flamingo feeds both day and night, especially at dawn and dusk (see Self Maintenance: Daily Time Budget). It generally forages in groups that can reach several thousands of individuals (10).

Effects of Feeding Activity on Aquatic Habitats

Greater Flamingo is considered an ecosystem engineer that can, through its foraging activity, modify aquatic habitats. It has been observed in exclusion experiments in tidal flats and coastal lagoons that it mobilizes sediments and nutrients in the water column by modifying the topography of the substrate and the benthic communities (161, 162, 163, 164, 165, 166, 160, 167, 168).

It also contributes to structuring shallow wetlands. During feeding, it uproots the submerged macrophyte Ruppia maritima (163). Foraging caused sediment disturbance and can have strong seasonal effects on the abundance and community structure of benthic communities of polychaetes, chironomids, gastropods, and ostracods in shallow wetlands of Guadalquivir marshes (Spain) (166). In temporary marshes of the Doñana National Park (Spain), exclusion experiments showed that Greater Flamingo caused a significant reduction in chironomid abundance and an increase in the proportion of larger larvae (164). Exclosure experiments in two lagoons in the Camargue (France) showed that it can affect in opposite ways the growth of plant species such as Zostera noltii or Ruppia cirrhosa: in one lagoon, Greater Flamingo negatively affected Ruppia cirrhosa cover from June to July, while in another lagoon with different plant communities, Greater Flamingo and Mute Swan (Cygnus olor) had a detrimental effect on Zostera noltii cover in April. They also reduced Chaetomorpha sp. cover from April to July, favoring Zostera noltii cover in July (165).

Exclusion experiments at Walvis Bay (Namibia) found flamingos caused sediment disturbance, with increased chlorophyll concentrations and a decrease of bacteria levels found within exclosures where sediment was undisturbed. The numbers of both copepods and ostracods were also higher inside than outside intertidal exclosures, with total macrofaunal abundance (including Polychaeta, Nemertea, Oligochaeta, and Crustacea) 1.5–3 times higher at exclusion sites (161).

In Parc National du Banc d’Arguin (Mauritania), intertidal mosaic formations are comprised of gullies, bowls, plateaus, and mounds. Feeding activities of Greater Flamingo, and to a lesser extent of fiddler crabs (Afruca tangeri), interact with hydrodynamic forces to create and maintain these microhabitats for biofilm production (diatoms, cyanobacteria and green algae) (167).

In Langebaan Lagoon (South Africa), during channel foraging, the sideways movements of the bill on the sediment surface enriched channels with benthic microalgae. This is likely because the feeding activity reduces macrofaunal abundance in channels, causing nutrient fluxes from sediments following flamingo foraging (168). Different foraging behaviors can also have contrasting effects on prey assemblages in marine soft-sediment ecosystems (160). For example, channel foraging creates channels that have stronger negative effects on macrofaunal abundance and surface-dwelling taxa than pits created by pit foraging.

In addition to its effects on plant and invertebrate communities, Greater Flamingo foraging can also affect nutrient and microbial dynamics in wetlands. In Fuente de Piedra Lake (Spain), aggregations of Greater Flamingo can increase nitrogen and phosphorus concentrations through guano inputs as well as sediment bioturbation during foraging. Foraging by flamingos thus can induce cascading effects on prokaryotic abundance, viruses, and dissolved nitrogen (169).

Diet

Major Food Items

The diet is very varied and consists of nematodes, annelids, crustaceans, mollusks, aquatic insects (both adult and larvae), and small fishes, as well as microalgae, seeds, and other plant material (48, 32, 4, 10). When food is scarce, Greater Flamingo sometimes ingests mud to extract its organic matter. The prey may be >0.5 mm (48, 157, 117). There is no published information on prey sizes from stomach contents. In an experimental study in captivity, mean prey length ranged between 9.4 mm for chironomid larvae, 9.7 mm for rice seeds, and 8.21 mm for a brine shrimp (Artemia sp.) (170).

In the following lists of prey items, names in brackets are the currently accepted name of a species, while the name as it originally appear in the publication is provided.

In Afghanistan, the stomach contents of a Greater Flamingo from Ab-I-Istada Lake included 3 water beetles, 10 Notonectidae (Hemiptera), 23 midge larvae, and abundant remains of black ants (171). In Pakistan, it was observed feeding at tidal pools of Karachi where small mullet fry were present, and seeds of Medicago lupulina and a sedge (Cyperus sp.) were found in the stomach contents (172). In India, the stomach contents of birds from Great Rann of Kutch (India) had seeds of Ruppia rostellata [Ruppia maritima] and Bolboschoenus maritimus (173), while two birds from Kandla (India) in September had fed on Chironomus larvae (171). In a sample of Greater Flamingo from the eastern shore of the Caspian sea (n = 7), seeds of Ruppia maritima and the Cyanobacteria Aphanothece were found in the diet. At Kara-Bogaz bay (Turkmenistan), the diet consisted mainly of brine shrimp (Artemia salina) (28).

In East Africa, the stomach contents (n = 6) of birds from Elmenteita Lake (Kenya) consisted of chironomid larvae, corixids, copepods, insect larvae, sedge seeds, algae, diatoms, and remains of plants (174). Specific prey items included Paradiaptomus africanus [Lovenula africana] (copepod), Sigara (Vermicorixa) lateralis, Micronecta scutellaris, Micronecta bleekiana jenkinae (corixids), and Cyperus laevigatus seeds; significant amounts of blue-green algae and diatoms were also found in one flamingo (175). The stomach contents of a bird from Port Sudan consisted of the gastropod Tympanotomus fluviatilis [Pirenella cingulata] (175).

In Spain, the seeds in the stomach contents of a sample of Greater Flamingo (n = 7) from El Hondo Natural Park (Alicante Province) were Ruppia sp. (71.4%) and Potamogeton pectinatus [Stuckenia pectinata] (28.6%) (176). A Greater Flamingo found dead at Guadalquivir marshes in January had 246 Ruppia maritima seeds and benthic ostracods in its gizzard (163). Also in Guadalquiver marshes, gizzard contents (n = 10) were comprised of seeds of Scirpus litoralis [Blysmus rufus] (10 individuals) and Bolboschoenus maritimus (3 individuals) (38). In Fuente de Piedra Lake, digestive tracts of birds found dead (n = 8) included unidentified nematodes, crustaceans (Cletocamptus retrogressus [Copepoda], Eucypris mareotica [Ostracoda], Branchinella spinosa [Anostraca], Moina salina, and Ephippia sp. [Cladocera]), insects (adults of Bledius sp. [Coleoptera], and larvae Chironimidae and Ephydridae [Diptera]), oospores of charophytes (Lamprothamnium papulosum,Tolypella hispanica, and Chara sp.), and seeds of macrophytes (Ruppia drepanensis and Althenia orientalis) (117).

In France, the gizzard contents (n = 11) of birds from the Camargue included Paludestrina acuta [Hydrobia acuta], Paludestrina procerula [Hydrobia acuta], Peringia ulvae (Mollusca), Sphoeroma marginatum [Lekanesphaera marginata] (Isopoda), and seeds of Juncaceae and Papilionaceae (177). Artemia sp. comprised most the diet of birds found dead in Camargue, and diptera larvae (Ephydra bivittata and Thinophilus achilleus) were found in feces (178).

Quantitative Analysis

A Greater Flamingo from Bhyandar (India) had ca. 1,100 seeds of Ruppia maritima, ca. 15,000 seeds of graminaceous plants, and ca. 1,000 chironomid larvae (171).

In Doñana National Park (Spain), all gizzards examined from dead individuals (n = 10) had seeds of Scirpus litoralis (mean 375 seeds ± 524.7 SD, range 5–1511), and three of them also had seeds of Bolboschaenus maritimus (mean 1.3 seeds ± 3.4 SD, range 0–11) (38).

In Fuente de Piedra Lake (Spain), the prey in seven gizzards of dead Greater Flamingo included crustaceans: Cletocamptus retrogressus (mean 333.4 ± 508.2 SD, range 8–1,177), Eucypris mareotica (mean 61.8 ± 152.3 SD, range 0–436), Moina ephippia (mean 20.0 ± 32.2 SD, range 1–96), Cladocera ephippia (mean 2.9 ± 3.1 SD, range 0–8), Branchinella spinosa (mean 2.1 ± 6.0 SD, range 0–17), Moina salina (mean 0.3 ± 0.5 SD, range 0–1); insecta: Bledius sp. (Coleoptera, mean 0.1 ± 0.4 SD, range 0–1), Chinonomidae larvae (Diptera, mean 0.1 ± 0.4 SD, range 0–1), Ephydridae larvae (Diptera, mean 0.1 ± 0.4 SD, range 0–1); nematoda: mean 0.8 ± 1.2 SD, range 0–3); plants: oospores of charophytes (mean 13.1 ± 13.5 SD, range 0–43), and seeds of macrophytes (mean 9.6 ± 9.2 SD, range 0–24) (117).

Food Selection and Storage

Greater Flamingo chicks store food in their crops. See Parental Care: Feeding.

Nutrition and Energetics

Mean energy requirements for females (1,785 kJ/day ± 208 SD) are lower than for males (2,170 kJ/day ± 235 SD) (179).

A study on captive individuals determined that Greater Flamingo is not able to ingest food in direct proportion to its abundance, with food intake rates either reaching an asymptote or following a sigmoidal curve (170). Deville et al. (170) speculated that the bill structure limited filtering capacity, preventing flamingos from fully exploiting higher densities of food (although such conditions would rarely be found in the wild). Furthermore, the energetic gain when it feeds on rice (intake rate = 0.45 kJ/s) was 16 times higher than when feeding on Artemia, and 375 times higher than when feeding on chironomid larvae (170).

Metabolism and Temperature Regulation

Energetic requirements were lower in summer (1,387 kJ day-1, July 2006) and greatest in winter (2,143 kJ day-1, December 1980) for both males and females (179). A cold spell in the Camargue (France) caused an increase in energy requirements of 6.5% for males and 7% for females, compared with mean values of the corresponding months without cold spells (179). Greater Flamingo seems to be very sensitive to freezing temperatures, as shown in the Camargue, where there were mass mortalities during cold spells (179).

Drinking, Pellet-Casting, and Defecation

At Fuente de Piedra Lake (Spain), adults used the freshwater at the mouth of a stream that diverted into the lake for drinking (150). At Lake Elmenteita (Kenya), flamingos regularly came to drink at the mouth of a small spring, and flamingos were more abundant at the site during the incubation period (33).

Recommended Citation

Salvador, A., M. Á. Rendón, J. A. Amat, and M. Rendón-Martos (2022). Greater Flamingo (Phoenicopterus roseus), version 2.0. In Birds of the World (S. M. Billerman, Editor). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.grefla3.02