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Jacanas

birds species aquatic south

Jacanas are eight species of distinctive birds that inhabit the marshy edges of ponds, lakes, rivers, and swamps, and that make up the family Jacanidae. Jacanas are tropical birds, breeding in central and northern South America, sub-Saharan Africa, Madagascar, South and Southeast Asia, and Australasia. Jacanas do not migrate, but they may wander widely if their local aquatic habitats dry out.

Jacanas range in body length from 6-20 in (15-51 cm). They have rather short, rounded wings, with an unusual, spiny projection from the wrist, and a stubby tail. Their legs are large, and their unwebbed toes and claws are extraordinarily long, and useful for supporting the weight of these birds as they walk gingerly over the surface-floating foliage of aquatic plants. Jacanas usually have a brightly colored patch of bare skin, known as a frontal shield, in front of their eyes and above the beak. The body of these attractive birds is generally colored cinnamon-brown, with bold patterns of black, white, or yellow. The sexes are similarly colored, but female jacanas are considerably larger than the males.

Jacanas fly weakly, but they run, swim, and dive well. They are commonly observed walking on aquatic plants, such as the floating leaves of water lilies and lotus. Appropriately, alternative common names for these birds include "lily-trotters" and "lotus-birds." Jacanas carefully glean this habitat for their food of aquatic insects, crustaceans, molluscs, and plant seeds. Jacanas often forage in loose groups.

Jacanas lay four eggs in a nest built of aquatic plants, which is often partially afloat. In most species, the male incubates the eggs and cares for the young birds. In fact, some species of jacanas are polyandrous, meaning that a single female will mate with several males and then lay eggs in each of their nests. In most species of jacanas, a female consorts with two to four males, although the number can be as many as 10 in the case of the pheasant-tailed jacana. Polyandry is a rare breeding system in birds.

Jacanas do not occur in North America, although the northern jacana (Jacana spinosa) of Central and northern South America is an occasional visitor to south Texas and Florida. The closely related wattled jacana (Jacana jacana) is a widespread species in the tropics of South America. Some taxonimists consider these two to be variants of the same species.

The African jacana (Actophilornis africanus) is a widespread bird of ponds and other wetlands in sub-Saharan Africa. The closely related Madagascar jacana (Actophilornis albinucha) only occurs on the island of Madagascar. The lesser jacana (Microparra capensis) is a rarer African species.

The bronze-winged jacana (Metopidius indicus) is widespread from India to Indonesia, as is the pheasant-tailed jacana (Hydrophasianus chirurgus), with its very long and distinctive tail feathers. The lotus-bird or comb-crested jacana (Irediparra gallinacea) ranges from Borneo and the Philippines through New Guinea and eastern Australia.


Bill Freedman

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over 4 years ago

this helped so much with my school project it is unbelievable!