Theglaucous macaw (Anodorhynchus glaucus) is a critically endangered or possibly extinct species of large, blue and grey South Americanparrot, a member of a large group of neotropical parrots known as macaws. Thismacaw is closely related toLear's macaw (A. leari) and thehyacinth macaw (A. hyacinthinus). InGuaraní, it is calledguaa-obi after its vocalizations.

Glaucous macaw
Illustration by Bourjot Saint-Hilaire
Conservation status
Critically endangered, possibly extinct (IUCN 3.1)[1]
CITES Appendix I (CITES)[2]
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Psittaciformes
Family:	Psittacidae
Genus:	Anodorhynchus
Species:	A. glaucus
Binomial name
Anodorhynchus glaucus (Vieillot, 1816)

The glaucous macaw is 70 cm (28 in) long. It is mostly pale turquoise-blue with a large, greyish head. The termglaucous describes its colouration. It has a long tail and a large bill. It has a yellow, bare eye ring and half moon-shaped lappets bordering the mandible.^[3]

This bird was native to north Argentina, south Paraguay, the chaco and llano region of Bolivia near the city ofSanta Cruz de la Sierra,^[4] northeast Uruguay, and Brazil. It became rare during the 19th century due to trapping andloss of habitat, and only two possible reports of wild birds were received in the 20th century. Expeditions by ornithologists to southwestern Paraguay during the 1990s failed to turn up any evidence of the species. Furthermore, only the oldest residents of the region had knowledge of the macaw, with the species last recorded in the 1870s.^[1] The bird's disappearance probably is linked to trapping of live adults for the wild bird trade and the wholesale felling of the yatay palm,Butia yatay, thenuts of which appear to have constituted its main food.^[5] Although suitable habitat remains inEl Palmar National Park, in the Argentine province ofEntre Ríos, as well as southern Brazil, no rumours of the bird's continued existence in the past several decades have proven credible.^{[citation needed]} A search conducted by Joe Cuddy and Tony Pittman in 1992 concluded that the birds were extinct in their former range.^[6] Rumours persisted that blue macaws were seen in Argentina and Bolivia with a dealer in Rosario, Argentina, offering live specimens. The late George Smith gave many talks rich in conservation information on macaws, including this species, which he stated was not extinct in the wild, but existed in remote areas of Bolivia where he had encountered trappers who could identify this species. Moreover, he stated that stands of pure palm existed "as far as the eye could see" when he flew over the area which is yet to be investigated.^{[citation needed]}

A 2018 study citing bird extinction patterns, the heavy destruction of its habitat, and the lack of any confirmed sightings since the 1980s recommended uplisting the species to Critically Endangered – Possibly Extinct.^[7]

• 3D view of specimens RMNH 110.103 and RMNH 110.114 atNaturalis, Leiden (requiresQuickTime browser plugin).
• Blue Macaws