Parrots are found on all tropical and subtropical continents along with Australia and the islands of the Pacific Ocean, South Asia, southeast Asia, southern regions of North America, South America and Africa.
Some Caribbean and Pacific islands are home to endemic species. By far the greatest amount of parrot species come from Australasia and South America. The lories and lorikeets range from Sulawesi and the Philippines in the north to Australia and over the Pacific as far as French Polynesia, with the greatest diversity being found in and nearby New Guinea.
Usa
The subfamily Arinae encompasses all the Neotropical parrots, along with the Amazons, macaws and conures, and range from northern Mexico and the Bahamas to Tierra del Fuego in the southern tip of South America.
The pygmy parrots, subfamily Micropsittinae, are a small genus restricted to New Guinea. The subfamily Nestorinae are three species of aberrant parrots from New Zealand. The broad-tailed parrots, subfamily Platycercinae, are restricted to Australia, New Zealand and Pacific islands as far as Fiji. The final true parrot subfamily, Psittacinae, includes a range of species from Australia and New Guinea to the species found in South Asia and Africa.
The centre of cockatoo biodiversity is Australia and New Guinea, although some species reach the Solomon Islands (and one species at one time occurred in New Caledonia), Indonesia and the Philippines.
Several parrot species enter the cool, temperate regions of South America and New Zealand. One species, the Carolina Parakeet existed in temperate North America, but was hunted to extinction in the early 20th century. Numerous species have been introduced in areas with temperate climates, and have established carport populations in some states of the Usa, the United Kingdom and Spain.
While a few parrot species are fully sedentary or fully migratory, the majority fall somewhere between the two, manufacture poorly understood regional movements, some species adopting an entirely nomadic lifestyle.
Extant species range in size from the Buff-faced Pygmy Parrot, at under 10 g (0.35 oz.) in weight and 8 cm (3.2 inches) in length, to the Hyacinth Macaw, at 1.0 meter (3.3 feet) in length, and the Kakapo, at 4.0 kg (8.8 lbs) in weight.
Amongst the families, the three Nestoridae species are all large parrots, and the cockatoos tend to be large birds as well. The Psittacidae parrots are far more variable, fluctuating the full spectrum of sizes shown by the family. The most determined bodily characteristic that characterises parrots is their strong, curved, broad bill.
The upper mandible is prominent, curves downward, and comes to a point. It is not fused to the skull, which allows it to move independently, and contributes to the great biting pressure these birds are able to exert. The lower mandible is shorter, with a sharp, upward facing cutting edge, which moves against the flat measure of the upper mandible in an anvil-like fashion.
Seed eating parrots have a strong tongue which helps to manipulate seeds or position nuts in the bill so that the mandibles can apply an thorough cracking force. The head is large, with eyes positioned sideways, which limits binocular vision, but greatly enhances peripheral vision. Cockatoo species have a movable crest of feathers on the top of their heads which can be raised for display, and retracted.
No other parrots can do so, but the Pacific lorikeets in the genera Vini and Phigys are able to ruffle the feathers of the crown and nape. The renowned colour of plumage in parrots is green, though most species have some red or an additional one colour in small quantities.
Cockatoos are the main irregularity to this, having lost the green and blue plumage colours in their evolutionary history they are now predominately black or white with some red, pink or yellow. Strong sexual dimorphism in plumage is not typical among the parrots, with some renowned exceptions, the most remarkable being the Eclectus Parrot.
Parrot Species
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