CR (PE)
Glaucous Macaw Anodorhynchus glaucus



Justification

Justification of Red List category

Habitat loss and capture for the cagebird trade have likely been the major causes of declines in this species. It was formerly widespread (yet local) in Paraguay, northern Argentina, southern Brazil and Uruguay. It had become rare by the early second half of the 19th century, and there have been only a few reports from the 20th century onwards. The last likely observations of the species were from Mbaracayu, Paraguay, in the late 1990s and 2001.

Following methods developed in a series of papers published in 2017 (Akcakaya et al. 2017, Keith et al. 2017, Thompson et al. 2017), Butchart et al. (2018) calculate the probability that the species is extant based on records and surveys as 0.425, and the probability it is extant based on threats as 0.127, and thus recommend it be classified as Critically Endangered (Possibly Extinct).

Population justification
This species became rare by the early second half of the 19th century, and there have been only a few reports from the 20th century onwards. The last likely observations of the species were from Mbaracayu, Paraguay, in the late 1990s and 2001. If a population remains it is likely extremely small. Following methods developed in a series of papers published in 2017 (Akcakaya et al. 2017, Keith et al. 2017, Thompson et al. 2017), Butchart et al. (2018) calculate the probability that it is extant based on records and surveys as 0.425, and the probability it is extant based on threats as 0.127.

Distribution and population

Anodorhynchus glaucus was formerly widespread but clearly very local in north Argentina, south Paraguay, north-east Uruguay and Brazil, from Paraná state southwards. It was endemic to the middle reaches of the major rivers (Uruguay, Paraná and Paraguay) and adjacent areas, with most records coming from Corrientes, Argentina. It became rare before, or early in, the second half of the 19th century. There were a few local reports in the 20th century, with the last probable observations and local reports in Mbaracayu, Paraguay in the late 1990s and 2001. Loss of yatay palm habitat and capture for the cage-bird trade are likely to have driven declines.

Ecology

It was reported mostly along major rivers, but this may reflect travellers' dependence on river transport rather than the species's true habitat requirements. It appears to have been adapted to consume palm nuts as its staple, and therefore presumably wandered into palm-savannas and potentially lightly wooded areas. The only palm in its range with the appropriate size and type of nut is the Yatay (or Chatay) palm Butia yatay (Yamashita and Valle 1993). It nested and roosted on cliffs and the average clutch-size was probably two eggs (Collar et al. 2014).

Threats

Settlement of the major river basins within its range was presumably accompanied by the widespread loss of palm-groves, either through direct clearance for agriculture or the suppression of regeneration by colonists' cattle. Yatay palm, which the species probably fed on, was targeted for clearance by early colonists as it is an indicator of good soil quality (Collar et al. 2014). Widespread loss of gallery forests could also have had an impact on the species (Collar et al. 2014). The size and appearance of the bird probably made it a significant target for hunters, and even the taking of young as pets could have been important. There is some evidence that it was traded, but little to support various claims that there has been recent trade in live specimens. Any current trade in eggs, skins or live specimens would obviously be extremely harmful.

Conservation actions

Conservation Actions Underway

CITES Appendix I and protected under Brazilian law. There have been various attempts (so far unsuccessful) to rediscover the species. There are ongoing funding proposals to attempt to finance a programme of work aimed at confirming this species's presence in the wild.

Conservation Actions Proposed

Conduct interviews with local people, especially former and active parrot trappers, to assess the likelihood that any populations remain. Prepare to follow-up on any positive data from these interviews.

Identification

70 cm. Large blue macaw. Pale turquoise-blue with large greyish head. Proportionally long tail and massive bill. Yellow, bare eye-ring and half-moon-shaped lappets bordering mandible. Similar spp. Lear's Macaw A. leari has a bluer head and is not sympatric, but specimens in trade could be confused. Hyacinth Macaw A. hyacinthinus is considerably larger and bulkier, more violet-blue in colouration and yellow lappets extend along the base of the mandible. Also not sympatric. Voice Unknown.

Acknowledgements

Text account compilers
Smith, D., Symes, A., Benstead, P., Butchart, S., Clay, R.P., Bird, J., Sharpe, C.J.

Contributors
Clay, R.P.


Recommended citation
BirdLife International (2024) Species factsheet: Glaucous Macaw Anodorhynchus glaucus. Downloaded from https://datazone.birdlife.org/species/factsheet/glaucous-macaw-anodorhynchus-glaucus on 27/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 27/12/2024.