Légende : Héron agami : curiosité. Marais de Kaw, Guyane. Référence Indigo : 18981
The Agami Heron has a height of just 70 cm. It can be distinguished from other herons especially by its predominantly chocolate-coloured plumage and its very long beak (2). The bird is described as solitary, grouping together only in the reproductive period, in small colonies. They are sometimes associated with other bird species The Agami heron is observed in Central and South America. However, its rarity and discreet behaviour mean that little is known about its biology or ecological status. It is a diurnal species. Some of its characteristics, like the length of its beak, its downy plumage or its partly nocturnal activity, place it in a separate genus (Agamia), within the family Ardeidae.
In May 2002, an IRD research team (1) conducting a scientific expedition to the Kaw Swamp in French Guiana, discovered an exceptionally extensive colony of Agami Herons, numbering about 900 nests. It is the largest nesting site ever seen for these birds.
The colony is located at the heart of the Guianan nature reserve, 40 km south-east of Cayenne, in an area surrounded by open water. Access can be gained only by helicopter. The site is hidden on a vegetation-covered bar and in deep shade overtopped by palm species. This reproduction area is also the gathering ground for several other marsh bird species, like the hoatzin and the anhinga, or snake bird, with some rare Ardeidae:the Cocoi Heron and the Great Egret. Heron nests were examined. A study was also made of both nocturnal and daytime behaviour of adult birds within or outside the colony. This work led to an estimate of 1800 individuals, representing 900 couples and as many nests. These are fixed on bushes and trees at a level of a little over two metres above water and measure about 15 cm in diameter and are built to 8 cm high. The Agami Herons breed asynchronously, in that they do not all lay their eggs at the same time of the season. Consequently, these nests hold young at different stages of development: eggs, chicks or juveniles already able to fly. Thick foliage protects them from the sun.
Marie Guillaume | alfa
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