Justification of Red List Category
This species qualifies as Critically Endangered because, overall, it is likely to have undergone an extremely rapid population reduction over the past three generations, such that the remaining population is likely to be tiny. However, there are some signs of recovery now.
In 2007 the population was estimated at 250-300 individuals including 70 birds discovered at a dry season roost site (Waugh 2007). Given the uncertainty over the number of mature individuals this is placed in the band 50-249 until better data are available.
There is evidence that the population is currently increasing moderately following successful conservation measures and near elimination of trade, which caused extremely rapid declines during the 1970s and 1980s (Asociación Armonía in litt. 2016, 2017). However, given its longevity the trend over the past three generations has still been negative and declines of over 80% during the period are suspected. Growth rate estimates generated by a Population Viability Analysis did not reach the rate of replacement needed for the population to remain viable in the long-term (Strem and Bouzat 2012).
Ara glaucogularis is known from the Llanos de Mojos in north Bolivia. There are two subpopulations: the northern subpopulation is found from west of Santa Ana eastwards across the upper río Mamoré, Beni, where the wild population was discovered in 1992 (Duffield and Hesse 1997, Yamashita and Barros 1997), to the eastern savannas; the southern subpopulation is found mostly in the Maraban province in Beni, close to the town of Loreto. In 2007, the total population was estimated to number 250-300 individuals occupying a range of c.4,000 km2, with 70 individuals discovered at a dry season roost site that year (Waugh 2007). An estimated 1,200 or more wild-caught birds were exported from Bolivia during the 1980s, suggesting that the population was formerly much higher (Yamashita and Barros 1997).
It utilises forest islands and gallery forest found fragmented throughout the Beni Savannas at an 80:20 ratio. Motacú palm Attalea phalerata is a principal food of all macaws in the area, with abundances ranging from 0-100% in forest islands in the savannas, and borders of gallery forest. It nests in cavities, hatching 1-3 eggs. Birds living in the north of the Llanos de Mojos breed around the end of the dry season (September and October) whilst birds in the south breed at the beginning of the wet season (November onwards) (Berkunsky et al. 2014). Preferred nesting cavities typically have a diameter of 30 cm or more and are found in trees with a diameter at breast height of 60 cm or more (Gould 2013a). The species is most frequently found in pairs, but small groups (7-9) do occur and one large roosting group of 70 is known, thought to be made up of non-breeding birds (I. Berkunsky in litt. 2012, J. Gilardi in litt. 2012).
It was severely threatened in the past by legal and illegal exploitation for the national and international cage-bird trade (A. Hesse in litt. 1999, I. Berkunsky in litt. 2012), although this has been radically reduced since 1984 (I. Berkunsky in litt. 2012). However in 2010 illegal trading of two recently-poached wild juvenile Blue-throated Macaws was uncovered (Berkunsky et al. 2011). The juveniles were eventually released into the wild, however this demonstrates that illegal poaching does still occur. All known breeding sites are on private cattle-ranches, where burning and clearing for pasture and tree-felling for fuel and fence posts have reduced the number of suitable nest trees and inhibited palm regeneration (Duffield and Hesse 1997, Hesse 1998, J. Gilardi in litt. 2012). However, cattle-rearing has occurred in the region since the 17th century (A. Hesse in litt. 1999); thus, the preferred food, the motacú palm Attalea phalerata, has been substantially reduced and is only regenerating slowly (B. Hennessey in litt. 2016). Nest-site competition from other macaws, toucans, bats and large woodpeckers is significant, and disturbance from mammals, birds and human activity may reduce the reproductive output of some pairs (J. Gilardi in litt. 2012). Between 2007 and 2012, 30 nests were monitored. Of these nests, 57% failed, with most failures occurring during incubation (Berkunsky et al. 2014). Reasons for nest failure were diverse but included disease, predation and abandonment. Botfly (Philornis spp.) infestations have been responsible for nest failures as have bees colonising nest sites, extreme weather events and parental neglect (Gould 2013a). Nestlings are vulnerable to predation from: Toco Toucan Ramphastos toco, Crane Hawk Geranospiza caerulescens, Great-horned Owl Bubo virginianus and Southern-crested Caracara Caracara plancus (Gould 2013a). Hunting to provide feathers for indigenous headdresses probably has an important impact in some areas (I. Berkunsky in litt. 2012).
There are fears that inbreeding within an increasingly fragmented population is resulting in reduced fertility (Loro Parque Fundación 2003). This is compounded by a lack of recruitment to the breeding population; during a five year study, no new breeding pairs were recruited (Berkunsky et al. 2014). Disease also represents a significant threat, particularly in areas where the species shares water sources with other bird species (Gould 2013a). A Population Viability Analysis found that changes in adult mortality had the greatest impact on estimates of extinction probability and population growth rates and that habitat loss and poaching also affected these estimates (Strem and Bouzat 2012).
Conservation Actions Underway
CITES Appendix I. Officially considered Critically Endangered at the national level in Bolivia (Ministerio de Medio Ambiente y Agua 2009). Asociación Armonía/Loro Parque Fundación produced a Blue-throated Macaw Recovery Plan in 2003. It was listed as endangered under the U.S.A. Endangered Species Act in November 2013 (Gould 2013b). Live export from Bolivia was banned in 1984, although illegal export was still evident in 1997 (Duffield and Hesse 1997). The Asociación Armonía/Loro Parque Fundación parrot trade monitoring project has recorded reduced levels of trade in the species (B. Hennessey in litt. 2008), but the large scale illegal trade infrastructure in Bolivia means there is the potential to start trapping again if there is the demand. Agreement has been reached with some landowners to control access and deter potential trappers, and negotiations with other landowners continue (Hesse 1998, A. Hesse in litt. 1999). Based on field surveys, recommendations have been made that the Paraparau region, Beni department, be given greater conservation priority (Tobias 2003).
Much of the remaining population occurs on private ranch-lands. Many landowners are sympathetic to conservation work on their lands and continued support will benefit the species's recovery. Local conservation work has involved planting trees that provide food for the species (Gould 2013a) and a nest box campaign which has been run since 2004 and has found that there is a great demand for suitable nesting cavities. The active management and monitoring of nest box use has helped to reduce the incidence of nest failure (Berkunsky 2010). A recent study found that birds more readily used nest boxes that were placed in the same tree, or very near to a nest site used in previous years (Berkunsky et al. 2014).
Asociación Armonía, with the help of the American Bird Conservancy and World Land Trust, completed the purchase of a 3,555 ha private reserve protecting at least 20 Blue-throated Macaw in November 2008 (BirdLife International 2008). The Barba Azul Nature Reserve protects important foraging and roosting sites for over 100 Blue-throated Macaw individuals from March to early November (Asociación Armonia in litt. 2016). With additional land purchases, the Barba Azul Nature Reserve was expanded to 5,000 ha (Anon. 2012) and in 2014 was expanded to almost 11,000 ha (Anon. 2014b). The reserve will be used for education, research and tourism and, with the support of Bird Endowment, an additional 100 nest boxes were due to be put in place for the 2008/2009 breeding season (B. Hennessey in litt. 2008). In 2017, another 80 nest boxes were added (Asociación Armonia 2018). The Loreto population fledged 71 chicks under the Armonia / Loro Parque Fundacion nest box program since 2006 (Asociación Armonia 2018). The World Land Trust also carries out nest-box provision, as well as the feeding of nestlings and other manipulations. Nest guarding and monitoring has also been introduced at nests that are particularly vulnerable to predation (Gould 2013a). Other measures include on-going surveys of potential areas where populations may persist; a pet trade monitoring programme in two main Bolivian cities, land acquisition programmes conducted in order to protect key habitat and populations, as well as reforestation programmes for the Motacú palm. There has been a widespread education programme, including pamphlets, posters, T-shirts, presentations, short-wave radio spots, video programmes, TV interviews, travel to the most remote ranches giving presentations on laptops, and creation of interpretation centres in the bottle-neck towns of Trinidad, Santa Rosa and Santa Ana. Artificial feathers have been successfully produced and marketed to local people to replace authentic Blue-throated Macaw feathers used in traditional headdresses (Anon. 2014a).
The population in captivity (some of which is held in captive-breeding facilities) is many times larger than the wild population. In 2009 a formal agreement was signed between the Loro Parque Fundación, Asociación Armonía, the Zoo Fauna Sudamericana and the Noel Kempff Mercado Natural History Museum which formalises the initiation of a managed cooperative breeding programme in Bolivia (Anon. 2008). Modelling the effect of different management strategies on the population dynamics showed that the reintroduction of 50 adult individuals would double the wild population within 10 years (Maestri et al. 2017).
Conservation Actions Proposed
Continue nest guarding and monitoring. Expand, monitor and improve nest boxes and the captive-breeding programme. Develop a reintroduction programme. Continue illegal pet trade monitoring and confiscations of all native parrots from traders. Lobby local and national government regarding illegal pet trade. Research and promote the acquisition of land for the species's long-term conservation, studies into habitat requirements and restoration, and sustainable tourism support. Conduct research on Motacú palm to understand how to manage and regenerate the habitat (Gould 2013a). Continue wide-ranging education programmes, especially in Santa Rosa and Santa Ana area - supported by interpretive centres. Promote alternatives to macaw feather head-dress usage. Develop tourism infrastructure on private reserve lands. Maintain a low level of population monitoring and occasional new surveys. Implement field research to identify principal health threats. Further research needed into post-breeding behaviour; a study from 2007 to 2012 suggested that successful pairs do not breed the following year and more work is needed to ascertain how common this behaviour is (Berkunsky et al. 2014). A monitoring project is planned to track movements during the breeding and non-breeding seasons. It is not possible to follow flocks during the non-breeding season due to flooding, so tracking work will provide important information on the species's movements during this period (Berkunsky et al. 2012).
85 cm. Large, blue-and-yellow macaw. Upperparts turquoise-blue, slightly duller on crown and brighter on rump. Underparts largely bright yellow but vent pale blue. Bare facial patch obscured by blue feather-lines merging into blue lower cheek and throat, separated from crown by narrow yellow stripe. Bare pink skin around base of bill. Large bill, long tail, and yellow iris. Sexes similar. Immatures have brown iris with undertail-coverts possibly paler turquoise and broadly edged yellow. Similar spp. Blue-and-yellow Macaw A. ararauna is larger, has a thicker tail, green fore-crown, no pink facial skin, and larger area of facial skin with black throat patch. A. ararauna has dark blue primaries and secondaries contrasting with pale blue coverts, whereas A. glaucogularis has all-dark blue wings. Voice Loud raucous calls when alarmed, but higher-pitched, softer and more nasal than A. ararauna. Typical loud call follows an alternating distinctive pattern. It also has a distinctive rolling introduction to its flight call.
Text account compilers
Sharpe, C.J., Stuart, T., Symes, A., Taylor, J., Benstead, P., Butchart, S., Calvert, R., Capper, D., Bird, J., Hermes, C., Ashpole, J, Khwaja, N.
Hesse, A., Gilardi, J., Tobias, J., Berkunsky, I., Hennessey, A.
BirdLife International (2021) Species factsheet: Ara glaucogularis. Downloaded from http://www.birdlife.org on 13/04/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 13/04/2021.