Polla Azul/Purple Gallinule/Porphyrio martinicus

Foto: Alex Pareja

Nombre en español: Polla Azul

Nombre en ingles: Purple Gallinule

Nombre científico: Porphyrio martinicus

Familia: Rallidae

Canto: Gabriel Leite

El calamoncillo americano (Porphyrio martinicus),​ también conocido como pollona azulpolla azulgallareta moradagallineta moradatingua azultagüita purpúrea y calamón de la Martinica, es una especie de ave gruiforme de la familia Rallidae que habita los pantanos y humedales de América. Esta especie se clasificaba antes como Porphyrula martinica, resultando los géneros Porphyrula y Porphyriosinónimos.

Foto: Ferney Salgado

Características

Es de tamaño mediano, inconfundible con sus patas amarillas grandes, plumaje púrpura azulado con un verde en la parte posterior, y el pico rojo y amarillo. Tiene un escudo frontal azul pálido y la parte inferior blanca. Las aves juveniles son castaños en lugar de púrpura.

Historia natural

Su hábitat de cría es el pantano tropical del sudeste de los Estados Unidos migra a las regiones tropicales, como Florida Centroamérica y el Caribe y Sudamérica.

El nido es una estructura flotante en un pantano. Pone cinco a diez huevos. Su colorido es crema con manchas color castaño.

La dieta es omnívora, incluye una variedad de plantas y materia animal, incluso semillas, hojas y frutas de plantas acuáticas y terrestres, así como insectos, ranas, caracoles, arañas, gusanos de tierra y peces. También sabe predar huevos y joven de otros pájaros.

Esta especie es rara en Europa occidental. Hay una especie similar en el sur de Europa, Porphyrio porphyrio, pero es un ave de mucho mayor tamaño.

American purple gallinule

This article is on the New-World purple gallinule (Porphyrio martinicus), not the Old-World purple gallinule which is the Purple swamphen (Porphyrio porphyrio).

The purple gallinule (Porphyrio martinicus) is a swamphen since it has the genus Porphyrio. They are in the order Gruiformes, which means «crane-like», and within the order there are cranes, rails, and crakes. The purple gallinule is a rail species which places them into the family, Rallidae. They are also known locally as the yellow-legged gallinule. The specific name martinica denotes «of Martinique».

Description

This is a medium-sized rail, measuring 26–37 cm (10–15 in) in length, spanning 50–61 cm (20–24 in) across the wings and weighing 141–305 g (5.0–10.8 oz). Males, averaging 257 g (9.1 oz) in mass, are slightly larger than females, at 215 g (7.6 oz) on average. An adult purple gallinule has purple-blue plumage that will shine green and turquoise when in good lighting. Adults also have a pale blue shield on their forehead, which connects with the red and yellow bill. Darkness or low light can dim the bright purple-blue plumage of the adult to make them look dusky or brownish, although the forehead shield color differentiates them from similar species such as common gallinules. Immature purple gallinules are a brown-bronze color, with purple feathers on chest, and the bill and forehead shield is pale in color. Juvenile birds are light brown with hints of green-bronze on the wings and back, and white under-tail coverts.

Purple gallinules have long legs with long toes that help them walk onto of the floating vegetation, by distributing their weight. They have an anisodactyl toe arrangement that also helps them to cling to plant stems. Adults have bright yellow legs and feet, immatures have brown-yellowish legs and feet, and juveniles have brown legs and feet.When they fly, which is short distances, their legs hang down.

Distribution and habitat

The habitat that this species is found in, is freshwater marsh that have dense stands of vegetation. These birds are found in the southeastern states of the United States during the breeding season. They are residents species in southern Florida, Gulf and Pacific coast of Mexico, parts of Central America, and Caribbean. During the non-breeding season, they are found more inland in parts of Central America. They can also be found within South America during migration, and sometimes strays can be found as far north as Canada. 

The species has the greatest pattern of vagrancy amongst rails, with individuals recorded as far west as California and the Galápagos Islands, as far north as Iceland and Labrador, as far south as Tierra del Fuego, and as far east as Great Britain, Portugal and Cape Verde.

This species has been recorded in Cape Province of South Africa 21 times. Of the 21 one times found within South Africa most all of the birds where juveniles, so it is very unlikely that a breeding ground will be established there. 

Foto: Daniel Avendaño

Ecology

Purple gallinules nest are floating nest that are within the dense vegetation along shallow margins of lakes, rivers, and marshes shorelines. They lay between five to ten eggs, that are a buff or pale pink with brown and purple spots. Purple gallinules nest and territories are defended by the monogamous pair, and the juveniles remain in the territory to help care for siblings.  Purple gallinules are omnivorous ground feeders. There is a variety of plant and animal matter within their diet. Some of the foods they consume are seeds, leaves and fruits of both aquatic and terrestrial plants, insects, frogs, snails, earthworms, and fish.  They have also been known to prey upon the eggs and young of other bird species. 

Courtship Behaviors

The courtship of purple gallinules occurs while they are standing, and can be displayed by both sexes. Courtship occurs when the birds of a pair have been separated, and then wander close to one another. They then perform the principle display which is performed by both sexes at the same time. This display entails the bird standing in a slightly bent forward position, with the neck outstretched, and holding the wings at an almost right angle to the body and bent at the wrist, so that the primaries are angled down. Following the principle display one or both of the birds, will strut and cut across the path of the other with half-lowered wings, or they will make a deep bow as they approach each other. 

Porphyrio martinicus

Wikipedia/eBird

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