Temporal range: Eocene – Recent
54 mya – present
|Range of Parrots, all species (red)|
Parrots are birds of the order Psittaciformes. There are roughly 372 species in 86 genera and they are found in most tropical and subtropical regions. The greatest diversity of parrots is found in South America and Australasia.
Parrots are intelligent birds. They have relatively large brains, they can learn, and they can use simple tools. Because some species have the ability to make sounds like human voices and have plumages with bright colors, many species are kept as pets. This includes some endangered and protected species.
Parrots have a heavy, in relation to their size, and compact body with a large head and a short neck. Their beaks are short, strong and curved. The two parts of the beak are very strong and used to break fruits and seeds. The tongue is large and strong.
They have strong legs, and clawed zygodactyl feet (with two toes facing forward and two toes facing back) that are very useful to climb up trees. Many parrots are vividly coloured, and some are multi-coloured. The plumage of cockatoos ranges from mostly white to mostly black, with a mobile crest of feathers on the tops of their heads. Most parrots exhibit little or no sexual dimorphism.
They form the most variably sized bird order in terms of length. The smallest of the parrots is the pigmy parrot (Micropsitta pusio) with and adult weight of 11.5 g (0.41 oz) and a length of 8.6 cm (3.4 in). With a length (from the top of its head to the tip of its long pointed tail) of about 95 cm (37 in), the hyacinth macaw (Anodorhynchus hyacinthinus) is longer than any other species of parrot, although half that length is tail.
The order is subdivided into three superfamilies: the Psittacoidea ('true' parrots), the Cacatuoidea (cockatoos) and the Strigopoidea (New Zealand parrots). The greatest diversity of parrots is found in South America and Australasia.
Numerous challenges are found in studying wild parrots, as they are difficult to catch and once caught, they are difficult to mark. Most wild bird studies rely on banding or wing tagging, but parrots chew off such attachments. Parrots also tend to range widely, and consequently many gaps occur in knowledge of their behaviour. Some parrots have a strong, direct flight. Most species spend much of their time perched or climbing in tree canopies. They often use their bills for climbing by gripping or hooking on branches and other supports. On the ground, parrots often walk with a rolling gait.
The diet of parrots consists of seeds, fruit, nectar, pollen, buds, and sometimes arthropods and other animal prey. The most important of these for most true parrots and cockatoos are seeds; the large and powerful bill has evolved to open and consume tough seeds. All true parrots, except the Pesquet's parrot, employ the same method to obtain the seed from the husk; the seed is held between the mandibles and the lower mandible crushes the husk, whereupon the seed is rotated in the bill and the remaining husk is removed. They may use their foot sometimes to hold large seeds in place. Parrots are granivores rather than seed dispersers, and in many cases where they are seen consuming fruit, they are only eating the fruit to get at the seed. As seeds often have poisons that protect them, parrots carefully remove seed coats and other chemically defended fruit parts prior to ingestion. Many species in the Americas, Africa, and Papua New Guinea consume clay, which releases minerals and absorbs toxic compounds from the gut.
Geographical range and body size predominantly explains diet composition of Neotropical parrots rather than phylogeny.
Lories, lorikeets, hanging parrots, and swift parrots are primarily nectar and pollen consumers, and have tongues with brush tips to collect it, as well as some specialised gut adaptations. Many other species also consume nectar when it becomes available.
Some parrot species prey on animals, especially invertebrate larvae. Golden-winged parakeets prey on water snails, the New Zealand kea can, though uncommonly, hunts adult sheep, and the Antipodes parakeet, another New Zealand parrot, enters the burrows of nesting grey-backed storm petrels and kills the incubating adults. Some cockatoos and the New Zealand kaka excavate branches and wood to feed on grubs; the bulk of the yellow-tailed black cockatoo's diet is made up of insects.
With few exceptions, parrots are monogamous breeders who nest in cavities and hold no territories other than their nesting sites. The pair bonds of the parrots and cockatoos are strong and a pair remains close during the nonbreeding season, even if they join larger flocks. As with many birds, pair bond formation is preceded by courtship displays; these are relatively simple in the case of cockatoos. In Psittacidae parrots' common breeding displays, usually undertaken by the male, include slow, deliberate steps known as a "parade" or "stately walk" and the "eye-blaze", where the pupil of the eye constricts to reveal the edge of the iris. Allopreening is used by the pair to help maintain the bond. Cooperative breeding, where birds other than the breeding pair help raise the young and is common in some bird families, is extremely rare in parrots, and has only unambiguously been demonstrated in the El Oro parakeet and the golden parakeet (which may also exhibit polygamous, or group breeding, behaviour with multiple females contributing to the clutch).
Only the monk parakeet and five species of lovebirds build nests in trees, and three Australian and New Zealand ground parrots nest on the ground. All other parrots and cockatoos nest in cavities, either tree hollows or cavities dug into cliffs, banks, or the ground. The use of holes in cliffs is more common in the Americas. Many species use termite nests, possibly to reduce the conspicuousness of the nesting site or to create a favourable microclimate. In most cases, both parents participate in the nest excavation. The length of the burrow varies with species, but is usually between 0.5 and 2 m (1.6 and 6.6 ft) in length. The nests of cockatoos are often lined with sticks, wood chips, and other plant material. In the larger species of parrots and cockatoos, the availability of nesting hollows may be limited, leading to intense competition for them both within the species and between species, as well as with other bird families. The intensity of this competition can limit breeding success in some cases. Hollows created artificially by arborists have proven successful in boosting breeding rates in these areas. Some species are colonial, with the burrowing parrot nesting in colonies up to 70,000 strong. Coloniality is not as common in parrots as might be expected, possibly because most species adopt old cavities rather than excavate their own.
The eggs of parrots are white. In most species, the female undertakes all the incubation, although incubation is shared in cockatoos, the blue lorikeet, and the vernal hanging parrot. The female remains in the nest for almost all of the incubation period and is fed both by the male and during short breaks. Incubation varies from 17 to 35 days, with larger species having longer incubation periods. The newly born young are altricial, either lacking feathers or with sparse white down. The young spend three weeks to four months in the nest, depending on species, and may receive parental care for several months thereafter.
As typical of K-selected species, the macaws and other larger parrot species have low reproductive rates. They require several years to reach maturity, produce one or very few young per year, and do not necessarily breed every year.
Intelligence and learning
Some grey parrots have shown an ability to associate words with their meanings and form simple sentences. Along with crows, ravens, and jays (family Corvidae), parrots are considered the most intelligent of birds. The brain-to-body size ratio of psittacines and corvines is comparable to that of higher primates. Instead of using the cerebral cortex like mammals, birds use the mediorostral HVC for cognition. Not only have parrots demonstrated intelligence through scientific testing of their language-using ability, but also some species of parrots, such as the kea, are also highly skilled at using tools and solving puzzles.
Learning in early life is apparently important to all parrots, and much of that learning is social learning. Social interactions are often practised with siblings, and in several species, crèches are formed with several broods. Foraging behaviour is generally learnt from parents, and can be a very protracted affair. Generalists and specialists generally become independent of their parents much quicker than partly specialised species who may have to learn skills over long periods as various resources become seasonally available. Play forms a large part of learning in parrots; play can be solitary or social. Species may engage in play fights or wild flights to practice predator evasion. An absence of stimuli can delay the development of young birds, as demonstrated by a group of vasa parrots kept in tiny cages with domesticated chickens from the age of 3 months; at 9 months, these birds still behaved in the same way as 3-month-olds, but had adopted some chicken behaviour. In a similar fashion, captive birds in zoo collections or pets can, if deprived of stimuli, develop stereotyped and harmful behaviours like self-plucking. Aviculturists working with parrots have identified the need for environmental enrichment to keep parrots stimulated.
Sound imitation and speech
Many parrots can imitate human speech or other sounds. A study by scientist Irene Pepperberg suggested a high learning ability in an grey parrot named Alex. Alex was trained to use words to identify objects, describe them, count them, and even answer complex questions such as "How many red squares?" with over 80% accuracy. N'kisi, another grey parrot, has been shown to have a vocabulary around a thousand words, and has displayed an ability to invent and use words in context in correct tenses.
Parrots do not have vocal cords, so sound is accomplished by expelling air across the mouth of the trachea in the organ called the syrinx. Different sounds are produced by changing the depth and shape of the trachea. Grey parrots are known for their superior ability to imitate sounds and human speech, which has made them popular pets since ancient times.
Although most parrot species are able to imitate, some of the amazon parrots are generally regarded as the next-best imitators and speakers of the parrot world. The question of why birds imitate remains open, but those that do often score very high on tests designed to measure problem-solving ability. Wild grey parrots have been observed imitating other birds.
The journal Animal Cognition stated that some birds preferred to work alone, while others like to work together as with grey parrots. With two parrots, they know the order of tasks or when they should do something together at once, but they have trouble exchanging roles. With three parrots, one parrot usually prefers to cooperate with one of the other two, but all of them are cooperating to solve the task.
Relationship with humans
Parrots may not make good pets for most people because of their natural wild instincts such as screaming and chewing. Although parrots can be very affectionate and cute when immature, they often become aggressive when mature (partly due to mishandling and poor training) and may bite, causing serious injury. For this reason, parrot rescue groups estimate that most parrots are surrendered and rehomed through at least five homes before reaching their permanent destinations or before dying prematurely from unintentional or intentional neglect and abuse. The parrots' ability to mimic human words and their bright colours and beauty prompt impulse buying from unsuspecting consumers. The domesticated budgerigar, a small parrot, is the most popular of all pet bird species. In 1992, the newspaper USA Today published that 11 million pet birds were in the United States alone, many of them parrots. Europeans kept birds matching the description of the rose-ringed parakeet (or called the ring-necked parrot), documented particularly in a first-century account by Pliny the Elder. As they have been prized for thousands of years for their beauty and ability to talk, they have also often been misunderstood. For example, author Wolfgang de Grahl says in his 1987 book The Grey Parrot that some importers had parrots drink only coffee while they were shipped by boat, believing that pure water was detrimental and that their actions would increase survival rates during shipping. Nowadays, it is commonly accepted that the caffeine in coffee is toxic to birds.
Pet parrots may be kept in a cage or aviary; though generally, tame parrots should be allowed out regularly on a stand or gym. Depending on locality, parrots may be either wild-caught or be captive-bred, though in most areas without native parrots, pet parrots are captive-bred. Parrot species that are commonly kept as pets include conures, macaws, amazon parrots, cockatoos, greys, lovebirds, cockatiels, budgerigars, caiques, parakeets, and Eclectus, Pionus, and Poicephalus species. Temperaments and personalities vary even within a species, just as with dog breeds. Grey parrots are thought to be excellent talkers, but not all grey parrots want to talk, though they have the capability to do so. Noise level, talking ability, cuddliness with people, and care needs can sometimes depend on how the bird is cared for and the attention he/she regularly receives.
Parrots invariably require an enormous amount of attention, care, and intellectual stimulation to thrive, akin to that required by a three-year-old child, which many people find themselves unable to provide in the long term. Parrots that are bred for pets may be hand fed or otherwise accustomed to interacting with people from a young age to help ensure they become tame and trusting. However, even when hand fed, parrots revert to biting and aggression during hormonal surges and if mishandled or neglected. Parrots are not low-maintenance pets; they require feeding, grooming, veterinary care, training, environmental enrichment through the provision of toys, exercise, and social interaction (with other parrots or humans) for good health.
Some large parrot species, including large cockatoos, amazons, and macaws, have very long lifespans, with 80 years being reported, and record ages of over 100. Small parrots, such as lovebirds, hanging parrots, and budgies, have shorter lifespans up to 15–20 years. Some parrot species can be quite loud, and many of the larger parrots can be destructive and require a very large cage, and a regular supply of new toys, branches, or other items to chew up. The intelligence of parrots means they are quick to learn tricks and other behaviours—both good and bad—that get them what they want, such as attention or treats.
The popularity, longevity, and intelligence of many of the larger kinds of pet parrots and their wild traits such as screaming, has led to many birds needing to be rehomed during the course of their long lifespans. A common problem is that large parrots that are cuddly and gentle as juveniles mature into intelligent, complex, often demanding adults who can outlive their owners, and can also become aggressive or even dangerous. Due to an increasing number of homeless parrots, they are being euthanised like dogs and cats, and parrot adoption centres and sanctuaries are becoming more common. Parrots do not often do well in captivity, causing some parrots to go insane and develop repetitive behaviours, such as swaying and screaming, or they become riddled with intense fear. Feather destruction and self-mutilation, although not commonly seen in the wild, occur frequently in captivity.
The capture of wild parrots for the pet trade, as well as hunting, habitat loss and competition from invasive species, has diminished wild populations, with parrots being subjected to more exploitation than any other group of birds. Measures taken to conserve the habitats of some high-profile species have also protected many of the less charismatic species living in the same ecosystems.
Origins and evolution
Europe is the origin of the first presumed parrot fossils, which date from about 50 million years ago (mya). The climate there and then was tropical. Several fairly complete skeletons of parrot-like birds have been found in England and Germany. On the whole it seems likely that these are not direct ancestors of the modern parrots, but related lineages which evolved in the northern hemisphere, and which have since died out.
The earliest records of modern parrots date to about 23–20 mya and are also from Europe. Subsequently, the fossil record—again mainly from Europe—consists of bones clearly recognisable as belonging to parrots of modern type. The southern hemisphere does not have nearly as rich a fossil record for this period as the northern, and contains no known parrot-like remains earlier than the early to middle Miocene, around 20 mya. The first unambiguous parrot fossil (as opposed to a parrot-like one) is found in the Miocene. It is an upper jaw, identical that of modern cockatoos.
Images for kids
Fossil dentary specimen UCMP 143274 restored as a parrot (left) or an oviraptorosaur
Parrot Facts for Kids. Kiddle Encyclopedia.