In 1805, Félix de Azara called it "El Azul", commenting that he observed pairs at 27° and 29° latitude and never further north, but he had information that they reached 33°. This species not only nested in tree holes, but rather in vertical cliffs along the Paraná and Uruguay rivers, and its diet was limited to fruits, seeds, and dates, as it did not possess the same strength as the Red Macaw (Ara chloropterus). He describes its plumage, noting that it is mostly light blue, less vivid on the ventral areas, with the head and nape dull, which turns brown on the sides of the lower jaw, and mentions that with the light, all the blue turns to green (Azara, 1805). Sick notes that this species was the smallest of the blue macaws, referring to those of the genus Anodorhynchus (Sick, 1977).

The species was described for science by Vieillot in 1816 based on Azara’s description (1805), from which Vieillot named it glaucus, remembering those color details. Based on the coordinates provided by Azara, the type locality was set around the city of Corrientes, Argentina, and extended to the south of the Entre Ríos province (Chebez, 1999).

Formally published data lack concrete details such as dates and location about the records, here is a compilation:

Its distribution covered eastern Paraguay, southern Brazil (Sick, 1977), northeastern Argentina (Azara, 1805), and northern Uruguay (Chebez, 1999).

In the early 19th century, it was common along the Paraná River, near Corrientes, Argentina, where the crew of anthropologist A. D´Orbigny sailed (Sick, 1977).

In 1820, Saint-Hilaire noted a relatively small macaw in Santa Catarina, Brazil, "very common", with bluish-green plumage and a yellow circle around the eye, which must have been this species (Saint-Hilaire, 1936 in Sick, 1977).

A communication from F. Sellow says that in December/January of 1823-24, a blue macaw nested in the cliffs near Caçapava do Sul, Rio Grande do Sul, Brazil (Stresemann, 1948 in Sick, 1977), which can only refer to this species (Sick, 1977).

On December 20, 1827, D´Orbigny, being in the northwest of Corrientes, along the Paraná River and near the rivers and marshes of Itaibaté and Santa Lucía, notes: "Along the entire length of the cliff, pairs of glauco green macaws could be seen scattered, whose sharp cries were constantly echoed by the forest. Each one showed itself in front of the large holes it digs in the cliff to lay eggs, or perched on the hanging branches of the trees that crown the coasts. These sharp cries were mixed with the no less unpleasant cries of the wild turkeys, which only stopped when we moved away from their nests" (Bertonatti, 2001).

In 1837, along the Paraná River, near Corrientes, Argentina, D´Orbigny’s crew used the meat of this macaw as food, where D´Orbigny commented that it was "so tough that he couldn’t eat it" (Sick, 1977).

By 1895, the species was considered "very rare" in Argentina (Holmberg, 1939).

In 1950, Raúl Vaz-Ferreyra made the last visual record of the species in the wild in northern Uruguay, Artigas department (Chebez, 1999).

In 1977, after reviewing almost all the existing material of the species, Sick notes that he found no record of this macaw in the Brazilian part of the Paraná River and mentions that it seems to indicate that the species is really extinct. He mentions the 3 blue macaws of Brazil with the following conservation status: Hyacinth Macaw (A. hyacinthinus): Vulnerable, Glaucous Macaw (A. glaucus): Extinct, and Lear’s Macaw (A. leari): Critically Endangered. Emphasizing that the Glaucous Macaw is a geographic representative of Lear’s Macaw (Sick, 1977).

The disappearance of this macaw, already at a time when the respective areas were little affected by civilization, leads us to suspect a natural decline, a genetic depletion of the species, and perhaps even a natural catastrophe caused by an epizootic, as may have occurred with the Carolina Parakeet (Conuropsis carolinensis) (Ridgely, 1980 in Sick, 1977). It was also one of the first species cited in the literature used as food for the local population (Sick, 1977), indicating that it was subjected to hunting. It is possible that some specimens were traded in amateur circles, and that others were not recognized, passing as the Hyacinth Macaw or Lear’s Macaw (Sick, 1977). On the other hand, it is believed that the species specialized in feeding on the Yatay palm (Butia yatay), and therefore was disadvantaged by the introduction of domestic animals in the areas where this species of palm thrived, as the palm groves under grazing pressure tend to decline, coupled with the fact that man also reduced the population of this palm species with his arrival (Yamashita & Valle, 1993). The Paraguayan War, or Triple Alliance War, which pitted Paraguay against Uruguay, Brazil, and Argentina between 1865 and 1870, may have also negatively contributed to its disappearance, as it overlapped with the geographical distribution of this macaw. The artillery, naval maneuvers, and troop movements in combat caused environmental damage to the riverside cliffs and other habitats occupied by these birds (Bertonatti, 2001).


Figure No. 1. Plate displayed at the Bernardino Rivadavia Argentine Museum of Natural Sciences, Autonomous City of Buenos Aires, Argentina, showing a photograph of the only specimen preserved in Argentina, which is not on display, belonging to the MACN collection.


Author of this compilation: Jorge La Grotteria - 27/05/2017

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