Macaws are among the most spectacular of nature's offerings. If hummingbirds are the rainforest's jewels, macaws are the masterpieces. These birds' bright colors flash through the rainforest like splashes across a painter's canvas. Among the twenty or so recognized species, every color of the rainbow is represented. What sets macaws apart from their cousins, the parrots, are:
(1) Geographical location (macaws are found only in the Neotropics)
(2) Large size (even the smallest macaw is bigger than all but the biggest parrots)
(3) Featherless skin around the facial area
(4) Long pointed tail
(5) Gaudy plumage
Like other parrots, macaws have strong, curved bills that are capable of breaking open the toughest nuts. Their feet have four toes, in two opposed pairs to grip branches.
Their varied environment, long lives and complex social structure may account for the high intelligence of these animals. Some researchers assert that parrots are capable of understanding human speech, resulting in the ability for limited conversation. However, the jury is out on the extent to which macaws understand the meaning of their human-taught vocalizations.
HABITAT AND DISTRIBUTION
Macaws are found in a wide variety of habitats from forest to arid regions, but are most numerous and rich in species in lowland tropical rainforest. They prefer floodplains but some species range to 5000 feet, in particular always being quite close to water. In the neotropics, macaws range into Central America and down to northern Argentina.
FEEDING AND DIET
In the wild, macaw staples are fruit and nuts. Their powerful beaks are capable of cracking open the hardest nuts, giving them access to food unavailable to other animals. Mornings and evenings these birds commute long distances between favorite roosting and feeding sites, one of the great spectacles of the rainforest—the best chance to see them in the wild.
Like other parrots, macaws feed in groups. Among their favorite foods are palm nuts, hard fruits accessible to the macaws by virtue of their powerful bills. Besides fruiting trees, the birds' communal feeding stations include exposed river banks, which provide river clay that the birds consume as a dietary supplement. The clay licks, like macaw vitamin pills, help keep the birds in optimum health. While scientists aren't 100% sure why the birds visit these sites, they are frequent and regular visitors. One scientist counted over 350 red-and-green macaws visited a single clay lick, using it every other day or so.
BREEDING
Macaws, like some other large parrots, mate for life. Within larger flocks, you'll see pairs flying together. Breeding attempts are made yearly, and the female lays two to four eggs. The blue-and-yellow macaw lays its eggs in the cavity of a dead palm tree, particularly the aguaje palm, Mauritia flexuosa. This strategy limits nest sites because a dead palm will last less than four years before it rots and falls over.
Macaws are slow breeders and have low reproductive rates in the wild. Predators and parasites kill many chicks so that less than two-thirds of nests result in young that fledge. Only one young is fledged even when successful. Often the young die of starvation despite the apparent abundance of food.
Scientists are trying to understand the limiting factors in the parents' feeding behavior that limits their ability to provide food to the additional chicks. After hatching, the young take several months to fledge, and many often fail at this stage, falling victim to waiting predators while learning the difficult task of navigating the complex environment.
CONSERVATION
Kricher (1997) suggests that macaws provide a opportunity for ecotourism due to their popularity. Given the difficulty of seeing animals in the rainforest, the habit of macaws to congregate on clay embankments is a unique chance to see these charismatic animals in the open and at leisure. Several species regularly visit the clay licks, including those most sought after by ecotourists.
Kricher cites a study that showed each macaw could generate over $4,000 a year in tourist revenue. Given the long lives of macaws, each bird could potentially be worth $150,000 in tourist dollars. Such "no-brainer" economics speak clearly to the need to conserve the birds' populations and natural habitat.
As their habitat inexorably diminishes, so the populations of Amazon macaws will undoubtedly decline. After habitat loss, the main threat to macaws is hunting for their feathers. The long tail feathers are popular for use in headdresses and other handicrafts. (Photo of macaw feather headdress.) Although Amazon Indians have historically used feathers in costumes and headdresses, this is less of a danger than deforestation.
Collection for the pet trade is not as big threat as it was before prohibitions were put on the export and import of the birds. Today, commerce is strictly controlled. However, illegal collecting continues.
None of the lowland rainforest species is in imminent danger of extinction, but most macaws are at risk and their trade is controlled by the CITES listing. All Amazon species are list as CITES or II. The hyacinth macaw and one or two other macaw species of open grassland are endangered. One species of macaw, Spix's macaw (Cyanopsitta spixii) from northeastern Brazil, is believed extinct in the wild (Butchart et al., 2003). We can only hope that other species will not suffer the same fate.
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