Painted Snipes (Rostratulidae)

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Painted snipes

(Rostratulidae)

Class Aves

Order Charadriiformes

Suborder Charadrii

Family Rostratulidae


Thumbnail description
Medium-sized, chunky waders with relatively long bills, rounded wings, and brighter, more intricately patterned plumage than true snipes, to which they bear only a passing resemblance

Size
7.4–10.9 in (19–28 cm); 2.3–7.0 oz (65–200 g)

Number of genera, species
2 genera; 2 species

Habitat
Lowland wetlands, including grassland, marshes, and agricultural areas (e.g., ricefields)

Conservation status
The Australian taxa, R. australis, for which species status has been proposed, may require listing as Endangered

Distribution
Sub-Saharan Africa, Madagascar, South and East Asia, Indonesia, the Philippines, Australia, and southern South America

Evolution and systematics

In the 1980s, DNA–DNA hybridization studies suggested that painted snipes are most closely related to jacanas (Jacanidae), while other near relatives appear to include the phalaropes (Phalaropodinae) and some members of the sandpipers (Scolopacidae). The superficial resemblance of painted snipes to true snipes (Gallinago), from which their English name derives, is considered to have no taxonomic importance. Certain skeletal and anatomical features of the painted snipes recall the Rallidae (rails) or Gruidae (cranes), as well as woodcocks (Scolopax) and seedsnipes (Thinocoridae). Jehl's 1968 proposal that painted snipes be grouped with jacanas in the superfamily Jacanoidea, most closely aligned to another such family containing the crab plover (Dromas ardeola), with all other shorebirds belonging to a third superfamily, has gained widespread support in subsequent literature. Lack of fossil material prevents an understanding of the evolutionary history of painted snipes.

Traditionally, the Rostratulidae have been considered to represent two species in the monotypic genera Rostratula (greater painted snipe) and Nycticryphes (South American painted snipe). However, research in 2000 recommends that the Australian form of greater painted snipe (Rostratula australis) be elevated to species status based on its longer wing, shorter bill and legs, and coloration. Australian greater painted snipe males have boldly spotted (not barred) wing-coverts and a paler gray tail, and females possess a mainly dark chocolate-brown (rather than rufous) head and neck and discrete, round tail spots. In addition, there appears to be clear differences in vocalizations between the two forms. Female R. australis almost never give the low booming advertising call that is so distinctive of nominate R. benghalensis. The authors of the new study, Lane and Rogers, speculate that Australian birds may lack the trachea and esophagus modifications that permit female R. benghalensis to make such calls.

Physical characteristics

The South American painted snipe (Nycticryphes semicollaris) is the smaller of the two/three species, measuring 7.4–9.0 in (19–23 cm) and weighing 2.3–3.0 oz (65–86 g). Like greater painted snipes (Rostratula bengalensis), its legs are strong and the toes are elongated. The bill is powerful and curves sharply downward at the tip (which has earned it the name "bicotorto," or crooked beak, in Brazil). The tip also broadens like a spatula and acquires a slight reddish tone. The head and neck are dark reddish brown with a conspicuous cream-colored crown stripe and a bright white spot at the base of the neck-sides. The wings are black-brown, marked by large snow-white round spots, and the abdomen is white. Males and females are hardly distinguishable, but the latter tend to be slightly larger and possess marginally brighter plumage. In contrast, greater painted snipes exhibit a marked difference in the coloration of the sexes. Females are considerably larger and more brilliantly patterned than males. The head and neck of females are a rich chestnut brown, whereas those of males are spotted and inconspicuous. Females have bronze-green wings and upperparts that are finely barred in black (which

look rather uniform at a distance), and males have ashy-gray upperparts that are extensively barred and spotted with golden buff, especially on the wing-coverts. Both genders have a striking pale eye patch that is elongated at the rear and a pale crown stripe and mantle V; these parts are bright white in females and golden in males. Juvenile South American painted snipes look similar to adults, but the spotting on their upperparts is reduced and cream-colored. Juvenile greater painted snipes resemble adult males but have grayer wings and reduced, paler spotting.

Distribution

Greater painted snipes are distributed widely through Africa, South and Southeast Asia, the Philippines, Indonesia, and eastern Australia. South American painted snipes are restricted to the southern third of South America.

Habitat

Lowland wetlands, including swamps, reedbeds, ricefields, man-made wetlands with sufficient cover, damp grassland, and cover along streams and rivers are all used by painted snipes. The South American species occasionally occupies more open habitats and is more restricted to true lowland habitats. Vagrant or migrant greater painted snipes are occasionally recorded at high altitudes (e.g., in the Himalayas or Tibetan Plateau). Habitat use by greater painted snipes is more closely governed by rainfall, especially in Africa where they will relocate to recently flooded areas, and they are usually absent from regions of lower rainfall.

Behavior

Painted snipes usually occur alone or in pairs, although exceptional groups of up to 100 greater painted snipes have been reported. These aggregations may be the result of localized populations being forced into a small area of remaining wetland as its surroundings dry out. Both species perform short-distance movements in response to changing water levels, but in Australia the nonbreeding areas are completely unknown; there is one record from New Zealand at this season.

Unlike South American painted snipes, where there is apparently no sexual role reversal, it is the female greater painted snipe that advertises for a mate. A number of displays have been described, and females take a lead in courtship by uttering prolonged series of low hooting notes, either from the ground or in a woodcock-like rolling flight. The calls are reminiscent of a hiccup or the noise made by blowing across an empty bottle. Such displays are principally given at twilight. The female has a convoluted trachea that is folded and measures twice the length of the neck; this configuration permits her to make strong calls.

Feeding ecology and diet

Painted snipes are omnivorous and eat small invertebrates, such as snails, earthworms, crustaceans, and insect larvae, as well as seeds of many grasses and cultivated grain. They probe soft mud or stand in shallow water and use a scything action of the bill to sift food. In greater painted snipes, much feeding occurs at twilight or at night.

Reproductive biology

The breeding biology of both species, particularly that of the South American species, is poorly studied. South American

painted snipes are monogamous and breed in loose colonies, with five or six nests found in 2.5–3.7 acres (1.0–1.5 ha). Greater painted snipes usually adopt a polyandrous mating system (females copulate with up to four males), although nests are often solitary. Both species construct shallow cups of reeds and grasses in waterlogged areas well-concealed by dense vegetation. Occasionally they build nests in more open wetlands. The male greater painted snipe's rather cryptic plumage serves as a defense, and he takes responsibility for nest-building, incubation, and chick-care duties. The division of parental duties (if any) are unknown in the South American painted snipe, as are incubation and fledging periods. Greater painted snipes lay two to five (usually four) eggs, and South American painted snipes lay two (rarely three) eggs. The chicks are precocial and nidifugous in greater painted snipes, being brooded for the first few days of life by the male. Young males become sexually mature at one year, whereas females probably are not sexually mature until they are two years old.

Conservation status

Neither of the traditionally recognized species is classified as being threatened, but should the Australian form R. australis be treated at species level, as has been proposed, it could warrant listing as Vulnerable, perhaps even as Endangered, under IUCN criteria. Declines have been particularly pronounced in the southeast, its traditional stronghold, and in the southwest of its range. Prolonged periods of drought may have caused locally significant population declines of greater painted snipes, while the destruction and alteration of native grasslands, especially in Argentina, are presumably causing similar losses in the South American species. Very few comparative data are available, and both species are still numerous in many areas.

Significance to humans

Like true snipes, painted snipes have long been regarded as part of the sportsman's bag. However, while South American painted snipes are highly prized in Argentina and Chile for their taste, the slow escape flight of greater painted snipes means that more competent marksmen often consider such sport too easy. Neither species is held in captivity with any frequency, although some studies have been made of greater painted snipes based on birds in collections or zoos.

Species accounts

List of Species

Greater painted snipe
South American painted snipe

Greater painted snipe

Rostratula benghalensis

subfamily

Rostratulinae

taxonomy

Rostratula benghalensis Linnaeus, 1758, Asia. A study published in 2000 recommended that R. australis demanded species-level recognition. Two subspecies.

other common names

English: Painted snipe, African painted snipe; French: Rhynchée peinte; German: Goldschnepfe; Spanish: Aguatero Bengalí.

physical characteristics

9–10.9 in (23–28 cm); female 3.2–6.7 oz (90–190 g), male 3.2–6.0 oz (90–170g). Female has rufous head and neck with bronze-green upperparts and wings, whereas male has ashy-gray head and heavily golden-spotted upperparts. Both sexes have largely white underparts, pale eye patches, a crown stripe, and a mantle V. Juvenile largely resembles adult male.

distribution

Madagascar and Sub-Saharan Africa, with the exception of the Congo Basin. To the east, it also occurs through South and Southeast Asia, north to Japan and extreme southeast Russia, east through the Philippines and Indonesia. The form australis

occurs in south Australia, Victoria, New South Wales, and parts of Queensland, with sporadic records from elsewhere in north Australia and west Australia.

habitat

Lowland wetlands, including human-made and human-modified areas.

behavior

Solitary or in small groups. Chiefly crepuscular (active at twilight) and partially nocturnal.

feeding ecology and diet

Omnivorous, probing mud or wading in shallow water in search of insects, crustaceans, seeds, etc.

reproductive biology

Polyanadrous or monogamous. Nests are usually solitary. Breeds year-round, chiefly following rains in Africa. Generally lays four eggs in shallow cup nest, concealed in marshy areas. Incubation, by male, 15–21 days, but fledging period unknown. Chicks precocial and leave the nest a short time after hatching; usually cared for by male alone.

conservation status

Widespread, can range from uncommon to frequent, but often locally common. Formerly widely hunted, especially in European colonies. Declining in some areas due to wetland drainage and drought conditions. Australian population of serious conservation concern and may require IUCN listing as either Vulnerable or Endangered.

significance to humans

Principally known to sport hunters, but apparently of little significance to local human populations.


South American painted snipe

Nycticryphes semicollaris

Subfamily

Nycticryphinae

taxonomy

Nycticryphes semicollaris Vieillot, 1816, Paraguay. Monotypic.

other common names

English: American painted snipe; French: Rhynchée de Saint-Hilaire; German: Weißflecken-Gold schnepfe; Spanish: Aguatero Americano.

physical characteristics

7.4–9.0 in (19–23 cm); 2.3–3.0 oz (65–86 g). Both sexes have a dark reddish brown head and neck, dark grayish brown and black upperparts and wings, the latter spotted white, and largely white underparts, pale eye patches, and a crown stripe. Females may tend to be larger and slightly brighter. Juvenile largely resembles adult.

distribution

Southern Brazil, Paraguay, and Uruguay to central Chile and central Argentina.

habitat

Lowland wetlands, including wet grasslands, estuaries, rivers and streams.

behavior

Solitary or in small groups. Chiefly crepuscular and partialy nocturnal. Largely sedentary, with some seasonal movements dictated by rainfall.

feeding ecology and diet

Omnivorous, probing mud or wading in shallow water in search of insects, larvae, crustaceans, seeds, etc.

reproductive biology

Monogamous. Nests semi-colonially. Breeds July through February, according to local conditions. Lays two or three eggs in shallow cup of grasses and reeds, often surrounded by water. Incubation and fledging periods unknown, but both sexes involved in chick care.

conservation status

Widespread, but usually uncommon or localized. Very few precise data concerning populations, but probably known from rather few protected areas. Presumably declining, especially in northeast Argentina, due to wetland drainage and conversion of grasslands to agriculture and forestry.

significance to humans

Highly prized by hunters in Argentina and Chile for its tender, tasty flesh, and often shot in the breeding season (at least formerly).


Resources

Books

del Hoyo, J., A. Elliott, and J. Sargatal, eds. Handbook of the Birds of the World. Vol. 3, Hoatzin to Auks. Barcelona: Lynx Edicions, 1996.

Snow, D.W., and C.M. Perrins, eds. Birds of the Western Palearctic Concise Edition. Vol. 1. Oxford: Oxford University Press, 1998.

Periodicals

Jehl, J.A. "Relationships in the Charadrii (shorebirds): a taxonomic study based on color patterns of the downy young." San Diego Society of Natural History Memoir 3 (1968): 1–54.

Lane, B.A., and D.I. Rogers. "The Australian Painted Snipe Rostratula (benghalensis) australis: an endangered species?" The Stilt 36 (2000): 26–34.

Guy M. Kirwan