Blue-throated Macaw(Ara glaucogularis)
The blue-throated macaw is about 85 cm long including the length of its tail feathers and has a wingspan of approximately three feet or 0.9 m. It weighs about 900-1,100 g. There is little easily observable sexual dimorphism; however, males tend to be a little bigger than females with approximate masses of 750-950 g respectively. Upperparts are turquoise-blue, slightly duller on crown and brighter on rump.
Underparts largely bright yellow but the vent is pale blue. It has bare facial patch obscured by blue feather-lines merging into blue lower cheek and throat, separated from crown by narrow yellow stripe and bare pink skin around base of the large, black bill. On the face there is a sparsely feathered patch of skin near the base of the large dark-coloured bill that has 5 or 6 horizontal stripes of blue feathers which are unique for every blue-throated macaw and can be used to individually identify adults.
The adults have yellow irises and the juveniles have brown irises. The eye colour of a nestling is initially black and changes to brown soon after the eyes open. Between one and three years old, the eyes will turn grey, then white. As the macaw matures, the iris turns yellow and the amount of gold increases with age after 10 years. Elderly macaws show a ring of dark grey surrounding the pupil where the iris has become thinner and the back of the retina shows through. It can be separated from the slightly larger blue-and-yellow macaw by the blue (not black) throat, the blue (not green) crown and the lack of contrast between the remiges and upperwing coverts.
Habitat
They are a macaw endemic to a small area of north-central Bolivia, known as Los Llanos de Moxos. They nest in "Islas" (islands) of palm trees that dot the level plains. It is not a forest dwelling bird. This species is one of the rarest in the world. There are two areas inhabited by two sub-populations: one is to the northwest of Trinidad (the capital city of Beni), and the other is to the south of Trinidad. This complex landscape consists of grasslands, marshes, forest islands, and corridors of forests along waterways. They occur most often between the elevations of 200-300 m.
Diet
Blue-throated macaws do not eat seeds and nuts to the same extent as many other macaw species do. Instead, they eat primarily fruit from large palms. The macaws eat the mesocarp from ripe and nearly ripe fruit and have also been observed drinking the liquid from very immature fruit.
Breeding
Blue-throated macaws usually breed once a year but if the eggs or nestlings are lost, they may produce a second clutch in the same breeding season. A clutch consists of one to three eggs and incubates for 26 days. Nestlings have a mass of approximately 18 g at hatching and fledge at 13-14 weeks. The young macaws are still fully dependent upon their parents for food after they fledge until they are capable of foraging by themselves. Even after this occurs, it has been observed that young blue-throated macaws will stay with their parents up to a year. During this time, the parents will skip an entire breeding season. Blue-throated macaws reach sexual maturity at about 5 years of age.
Population
According to the IUCN Red List, they are classed as Critically Endangered(CR). In 2007 the population was estimated at 250-300 individuals including 70 birds discovered at a dry season roost site. 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. 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.
Threats
It was severely threatened in the past by legal and illegal exploitation for the national and international cage-bird trade, although this has been radically reduced since 1984. However in 2010 illegal trading of two recently-poached wild juvenile Blue-throated Macaws was uncovered. 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. However, cattle-rearing has occurred in the region since the 17th century; thus, the preferred food, the motacú palm Attalea phalerata, has been substantially reduced and is only regenerating slowly. 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. 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 (Philornisspp.) infestations have been responsible for nest failures as have bees colonising nest sites, extreme weather events and parental neglect. Nestlings are vulnerable to predation from: Toco Toucan, Crane Hawk, Great-horned Owl and Southern-crested Caracara. Hunting to provide feathers for indigenous headdresses probably has an important impact in some areas. There are fears that inbreeding within an increasingly fragmented population is resulting in reduced fertility. This is compounded by a lack of recruitment to the breeding population; during a five year study, no new breeding pairs were recruited. Disease also represents a significant threat, particularly in areas where the species shares water sources with other bird species. 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.
Conservation
Conservation Actions Underway
CITES Appendix I. Officially considered Critically Endangered at the national level in Bolivia. 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. Live export from Bolivia was banned in 1984, although illegal export was still evident in 1997. The Asociación Armonía/Loro Parque Fundación parrot trade monitoring project has recorded reduced levels of trade in the species, 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. Based on field surveys, recommendations have been made that the Paraparau region, Beni department, be given greater conservation priority. 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 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. 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.
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. The Barba Azul Nature Reserve protects important foraging and roosting sites for over 100 Blue-throated Macaw individuals from March to early November. With additional land purchases, the Barba Azul Nature Reserve was expanded to 5,000 ha and in 2014 was expanded to almost 11,000 ha. 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. In 2017, another 80 nest boxes were added. The Loreto population fledged 71 chicks under the Armonia / Loro Parque Fundacion nest box program since 2006. 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. 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. 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. 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.
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. 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. 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.