Lear's macaw (Anodorhynchus leari), also called the indigo macaw, is a large, bright blue parrot from Brazil. It belongs to a group of parrots called macaws, which are found in the Neotropical region. The bird was first described by Charles Lucien Bonaparte in 1856. Lear's macaw is 70–75 cm (27.5–29.5 in) long and weighs about 950 g (2 lb 2 oz). Its body is mostly blue, with a yellow patch of skin near the base of its large, black beak.
Although people in Britain saw this bird as early as the 1830s, it was not widely recognized as a separate species until the late 1970s. Lear's macaw is very rare and lives in a very small area. Its natural habitat was discovered in 1978. Conservation efforts have helped increase the global population about thirty times in the first two decades of the 21st century. The bird lives in a dry, shrubby environment called caatinga and nests in holes in sandstone cliffs. It mainly eats the nuts of the palm tree Syagrus coronata and sometimes takes maize from local farmers. Its survival is also connected to cattle ranching.
Taxonomy
Lear's macaw is named after Edward Lear, a well-known poet and skilled artist. In the 1830s, when he was a teenager, Lear created a book titled Illustrations of the Family of Psittacidae, or Parrots, which included drawings and paintings of parrots in zoos and collections. One of his paintings closely resembled Lear's macaw. At the time, he labeled the painting as "hyacinth macaw," a different species that is larger, darker, and has a distinct yellow patch near the base of its beak. Not all people agreed that the painting showed a new species. In 1856, the French ornithologist Prince Charles Lucien Bonaparte, who was also the nephew of Emperor Napoleon, gave the illustration a scientific name to honor Edward Lear. However, most experts did not believe the bird was a separate species. It was not officially recognized as a distinct species until 1978, when German-born ornithologist Helmut Sick discovered the wild population in Brazil.
Description
Lear's macaw is 70 to 75 centimeters (27.5 to 29.5 inches) long and weighs about 950 grams (2 pounds 2 ounces).
The body, tail, and wings are dark blue with a faint, barely visible green color. The head is a slightly lighter shade of blue. There is a pale-yellow area of skin next to the base of the beak, and orange-yellow rings around the eyes. The beak is large and blackish, and the feet are dark grey.
Lear's macaw is similar to the larger hyacinth macaw and the slightly smaller glaucous macaw. The hyacinth macaw has darker feathers, no greenish color, and a differently shaped patch of yellow skin near the base of the beak. The glaucous macaw is lighter in color and has a more greyish head.
Ecology and behaviour
Lear's macaw mainly eats the nuts of the licuri palm (Syagrus coronata), consuming up to 350 per day. They also eat seeds from several plants, including Melanoxylon, Jatropha mollissima, Dioclea, Spondias tuberosa, Schinopsis brasiliensis, and Zea mays (maize), as well as the flowers of Agave.
The macaws often search for food in groups. They prefer to feed in areas where licuri palms grow in clusters among taller trees. At least thirty known feeding sites exist across their range. A flock typically selects a tall tree as a base to examine the area. A pair of macaws first descends to the level of the palms to check if the location is suitable. After returning to the base, the entire flock descends to decide if the site is worth using. If it is, the macaws feed directly at the site, tearing the fibrous pulp from the fruit to access the hard, thick-shelled nuts. The pulp is discarded. Their strong, chisel-shaped bills are specifically adapted to crack open the nuts. Sometimes, the birds fly to a higher perch to eat the nuts, carrying a branch with fruit. These perches are often branches of tall trees or cliff faces. The ground below these perches becomes covered with piles of cracked nut shells, making them easy to spot.
A mystery in the Neotropics involves how plants with large fruits or seeds spread their seeds. In other parts of the world, large herbivorous mammals help with this, but such animals are mostly absent in South America today. Scientists believe that these mammals once helped spread seeds, but their extinction during the Late Pleistocene left large-fruited plants unable to spread their seeds effectively until humans introduced livestock. However, the licuri palm may have avoided this issue. Lear's macaws are messy eaters, and a study found many undamaged nuts on the ground below branches or rocks where the birds carry their harvest.
A possible way the birds help spread the nuts is by eating seeds that cattle regurgitate. Cattle eat the licuri fruit but usually cough up the large seeds, which are cleaned of pulp. These seeds often gather in areas where cattle rest and may still be viable. Lear's macaws gather at cattle corrals and walk on bare ground near these sites to find the regurgitated nuts. After finding one, the macaws often eat it on a high perch elsewhere. Cattle also change the environment by creating open spaces, which may mimic the original ecosystem of Bahia before native megafauna disappeared. Around 11,000 years ago, macaws may have lived alongside giant herbivores in northeast Brazil, and the licuri palm relied on these animals for seed dispersal.
Lear's macaw sometimes causes problems for local farmers by eating maize (Zea mays) from their fields. To reduce conflicts, a program was started in 2005 to compensate farmers for crop losses by providing maize from other areas. During the pandemic, this program was paused because many farmers were elderly, but the macaws were not shot due to restrictions on selling corn.
The mating season begins with the start of summer rains at the beginning of the year and lasts until May, when the young birds leave the nest. A pair of Lear's macaws lays two to three eggs each year. The eggs are incubated for about 29 days. While some pairs raise three chicks, the average survival rate is two per pair. Not all pairs in the wild mate regularly or at all. The young stay with their parents for up to a year. Juveniles reach sexual maturity at around 2 to 4 years of age.
Distribution and habitat
For about 150 years after its discovery, the species was only seen occasionally in the bird trade, and no one knew where the wild birds lived. In 1978, ornithologist Helmut Sick found a wild population in Bahia, in the northeast interior of Brazil. Before this discovery, people believed the birds were just a type of the closely related hyacinth macaw.
Lear's macaw sleeps on sandstone cliffs formed by streams eroding rock formations. It is known to live in two colonies near Toca Velha and Serra Branca, south of the Raso da Catarina plateau in northeast Bahia. In 1995, a group of 22 birds was found at Sento Sé/Campo Formoso, 200 km (120 mi) to the west.
From these roosting sites, the macaws travel across several regions, including the municipalities of Campo Formoso, Canudos, Euclides da Cunha, Jeremoabo, Monte Santo, Novo Triunfo, Paulo Afonso, Santa Brígida, and Sento Sé. They depend on licury palm forests for much of their food. These palm forests once covered 250,000 km² (97,000 sq mi) in Brazil but have been greatly reduced due to farming. Cattle grazing in these areas harms young licury palms, making it hard for new trees to grow. In response, tens of thousands of licury palms were planted in protected areas starting in the early 2000s.
Lear's macaw also needs natural cavities in sandstone cliffs to nest. The limited number of these cavities may restrict population growth. Because of this, some conservationists suggested digging artificial cavities to help the birds nest.
Conservation
This species is currently listed as an endangered species (CITES I).
Yamashita, one of the first scientists to study this bird in the wild, estimated that the global population numbered about 60 birds in 1983. By 1987, the population had increased to about 70 birds. A survey in 2000 counted approximately 170 individuals. BirdLife International (BI), which writes the IUCN Red List assessments, estimated the population at 150 birds in 2000. BI noted that the population growth was decreasing but did not explain why. Surveys in 2001 counted 246 birds (Gilardi), 455 in 2003, and 570 in 2004 (IBAMA). In 2004, BI estimated the population at 246–280 birds but still claimed the population was decreasing. In 2006, Barros counted 630 birds. In June 2007, Fundação Biodiversitas staff counted 751 individuals. In 2008, Develey counted 960 birds. BI later stated that earlier surveys might have missed some birds and that the population was not actually increasing. BI estimated 250–500 mature wild individuals in 2008, suggesting that many birds counted in recent surveys might have been young birds, not adults. BI noted that if the number of adults grew beyond 250, the species might need to be reclassified in the future. BI stated that the population growth was uncertain, as some birds were trapped for the pet trade in the 1990s, which caused a rapid decline.
BI classified the species as "critically endangered" until 2008, though this was likely incorrect. In 2000, 2004, and 2008, the reason for the "critically endangered" status was listed as criterion C2a(ii), which does not apply to "critically endangered" species but does apply to "endangered" species. This criterion states that if 95% or more of the population is in a single subpopulation and the total population is 2,500 or fewer, the species should be assessed as endangered. However, it was known that the species had at least two subpopulations, possibly three, but BI incorrectly reported this in the population section of the assessment.
In 2009, BI downgraded the species to "endangered" because it was clear the population was growing rapidly. BI estimated the population remained at 250–500 individuals, claiming most of the rest were likely sub-adults. BI stated the population growth was still uncertain. The species was assessed as endangered based on criteria B1ab(iii), which refers to habitat fragmentation and declining habitat quality. In 2010, Barbosa counted 1,123 birds at two roosting sites, with at least 258 adults. By 2012, the estimated population had grown to 250–999 individuals. The number of subpopulations was listed as two. Lugarini et al. counted 1,263 birds in 2012. A 2012 survey of a third subpopulation found only two macaws. The 2013 assessment was similar to 2012. The 2016 assessment estimated the population as 250–999 individuals, with growth still uncertain. BI updated the number of adults to 228. The 2017 assessment was the same as 2016 but included a map showing the roosting areas of the two subpopulations.
In 2014, Chico Mendes Institute for Biodiversity Conservation (ICMBio) counted 1,294 birds. This number increased to 1,354 in 2017 and 1,694 in 2018. In 2019, BI estimated the population at 250–999 individuals but noted the population was growing. A map was updated to show foraging areas, not just roosting sites. The "Threats" section emphasized habitat loss from agricultural expansion. A 2014 study by Pacífico et al. found that 20.3% of the population was actively breeding, indicating at least 228 mature individuals. By 2018, about 340 birds were reproductively active adults. Of the nests monitored, 80% showed successful reproduction, a high rate compared to other parrots.
Historically, Lear's macaw may have been hunted, and in the 1990s, trapping for the pet trade caused a decline.
In 1991, Fundação Biodiversitas created the Canudos Biological Station to protect the sandstone cliffs of Toca Velha, where the macaws roost and nest. The station was expanded in 2007 to 3,649 acres with help from the American Bird Conservancy.
Two protected areas established in 2001 by the Brazilian government help conserve parts of the range: Raso da Catarina Ecological Station (104,842 hectares, managed by ICMBio) and Serra Branca/Raso da Catarina Environmental Protection Area (67,234 hectares, managed by the state agency of Bahia). The latter includes the privately owned Canudos Biological Station and Serra Branca ranch, which contains most of the nest and roost sites.
Current conservation efforts are managed by IBAMA, with support from ICMBio, local ranchers, and independent organizations.
In 1992, the "Special Working Group for the Preservation of the Lear's Macaw" was formed. In 1997, the "Committee for the Preservation of the Lear's Macaw (Anodorhynchus leari)" was created. In 1999, this committee merged with that of A. hyacinthinus and was renamed "The Committee for the Recovery and Management of the Anodorhynchus leari Lear's Macaw and Anodorhynchus hyacinthinus Hyacinth Macaw."
Aviculture
One of the earliest known records (and one of the few) of a Lear's macaw in a public zoo was a special exhibit featuring four blue-colored macaws, including Lear's, glaucous, hyacinth, and Spix's macaws, in 1900 at the Berlin Zoo.
According to the World Parrot Trust, the Lear's macaw is currently very rare in captivity and may live for 60 years. However, the Animal Ageing and Longevity Database reports the longest recorded lifespan of a captive Lear's macaw as 38.3 years. Experts recommend that this parrot be kept in an enclosure that is 15 metres (49 feet) in length.