The Gray Parrot is one of the largest parrot species in Africa. Both males and females have pale gray feathers with whitish edges on the head and neck, darker grey flight feathers, and short, striking red tails. The beak is black, and white facial skin surrounds pale yellow eyes.
African grey parrots (Psittacus erithacus) span the forest belt of central and West Africa including the oceanic island of Príncipe (Gulf of Guinea). In Western Africa, they are found in coastal countries such as Sierra Leone, Ghana, and the Ivory Coast. The two known subspecies of African Grey Parrots have varying ranges. Psittacus erithacus erithicus inhabits a range extending from Kenya to the eastern border of the Ivory Coast and including the insular populations. Psittacus erithacus timneh has a range from the eastern border of Ivory Coast to Guinea-Bissau.
Biogeographic Regions: ethiopian (Native )
- Melo, M., C. O'Ryan. 2007. Genetic differentiation between Principe Island and mainland populations of the grey parrot (Psittacus erithacus), and implications for conservation. Molecular Ecology, 16: 1673-1685.
The plumage of Psittacus erithacus is various shades of grey with very distinctive red tail feathers. African grey parrots typically measure 33 cm from head to tail and weigh up to 407g. They have an average wingspan of 46-52 cm.
Psittacus e. erithacus> is referred to as the nominate race and is light grey. Individuals of this subspecies have distinct red tails and solid black beaks. These birds have bare white face patches and sometimes bright, usually pale, silvery yellow eyes. Many of the grey contour feathers are edged with white. This gives them a smooth, lacy appearance. They may be somewhat sexually dimorphic.
Psittacus e. timneh individuals are smaller and darker with a maroon, brownish wash over the red tail. They have black-tipped, dark pinkish maxilla and solid black mandibles. Their iris has more of a silver appearance rather than yellow
Average mass: 407 g.
Average length: 33 cm.
Range wingspan: 18 to 20 cm.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: sexes colored or patterned differently
Habitat and Ecology
The habitat of African grey parrots is usually moist lowland forests, although they are found up to 2,200 m altitude in the eastern parts of the range. They are commonly observed at forest edges, clearings, gallery forests, mangroves, wooded savannahs, cultivated areas, and gardens. African grey parrots often visit open land adjacent to woodlands, they roost in trees over water and may prefer roosting on islands in rivers. These parrots make their nests in tree holes, sometimes choosing locations abandoned by birds like woodpeckers. In West Africa, the species makes seasonal movements out of the driest parts of the range in the dry season.
Habitat Regions: tropical ; terrestrial
Terrestrial Biomes: savanna or grassland ; forest ; scrub forest
Other Habitat Features: suburban ; agricultural ; riparian
- 2008. "Psittacus erithacus, Linnaeeus, 1758" (On-line pdf). Accessed March 20, 2008 at http://www.cites.org/eng/com/AC/22/E22-10-2-Al.pdf.
- Athan, M., D. Deter. 2000. The African Grey Parrot Handbook. Hauppauge, NY: Barron's Educational Series. Accessed March 20, 2008 at http://books.google.com/books?id=qqrxmrS2bXQC.
Gray Parrots range throughout the forested regions of central and western Africa including the oceanic island of Príncipe. Their preferred habitat is moist lowland forests, although they are routinely observed at forest edges and in clearings, mangroves, wooded savannas, cultivated areas, and gardens.
African grey parrots are herbivores. In the wild, they feed primarily on nuts and fruits, supplemented by leafy matter, fruits, insects, bark, and flowers. African grey parrots eat mostly common fruits, such as oil-palm (Elaeis guinensis).
Animal Foods: insects
Plant Foods: leaves; seeds, grains, and nuts; fruit; flowers
Primary Diet: herbivore (Frugivore , Granivore ); omnivore
- Faye, S. 2006. "African Greys aka Grey Parrots, General Info on the African Grey" (On-line). AvianWeb:Pet Bird Resources. Accessed April 10, 2008 at http://www.avianweb.com/aricangreys.htm.
African grey parrots may disperse the seeds of fruits they eat. They act as definitive hosts to both tapeworms and blood parasites.
- tapeworms (Cestoda)
- blood parasites
Psittacus erithacus are harassed and preyed on by palm-nut vultures (Gypohierax angolensis). Several species of hawks also prey on fledglings and adults. Monkeys prey on eggs and young in nests. When feeding on the ground, African grey parrots are vulnerable to terrestrial predators.
Life History and Behavior
Communication and Perception
Wild African grey parrot flocks follow a daily pattern of vocalizations. Usually the flock is quiet from sunset until the next dawn. At day break, the flock begins to vocalize before setting out to forage at different locations throughout the day. At dusk, upon return to the roosting site, there is a period of vocalization. There are a variety of different types of calls and vocalizations, including alarm calls, contact calls, food begging calls, and agonistic calls. Contact calls are of particular importance because they serve to identify where other members of the flock are and help promote flock cohesion. Alarm calls indicate varying levels of distress, these calls are particularly loud and of a frequency that carries well in order to warn fellow flock members. Young learn these vocalizations from parents and flock mates, so pet parrots will not learn appropriate vocalizations, but will show similar patterns and use of calls. Bottoni et al. (2003) found that African grey parrots demonstrated complex cognitive competence in understanding both the similarities and dissimilarities among musical note frequencies and were able to master the musical code. It was determined that African grey parrots must isolate a sound from background noise, imitate it, categorize the acoustic stimulus, encode it into long term memory, and monitor the output sound to match it with the internal template. The famous African grey parrot, Alex, achieved a rudimentary form of communication, including contextual and conceptual use of human speech. That research showed that African grey parrots are capable of far more than simply mimicing human speech.
Communication Channels: visual ; acoustic
Other Communication Modes: mimicry ; choruses
- Bottoni, L., R. Massa, D. Boero. 2003. The Grey Parrot (Psittacus erithacus) as a Musician: an Experiment With the Temperate Scale. Ethology Ecology and Evolution, 15: 133-141.
- Pepperberg, I. 2000. The Alex Studies, Cognitive and Communicative Abilities of Grey Parrots.b. Boston, Massachusetts: Harvard University Press.
In the wild, Gray Parrots feed on nuts and fruits, especially on common fruits such as the oil-palm. They may be important seed dispersers for the trees on which they feed. Gary Parrots supplements their diets with insects and other types of vegetation including leafy matter, bark, and flowers.
Gray Parrots form large, noisy flocks, where they call to each other with a variety of squawks, whistles, shrieks and screams. These highly social birds form lifelong pair bonds. The nesting female incubates the eggs while the male guards and feeds her. After hatching, both parents care for the young.
In captive and wild parrots the average lifespan is between 40 and 50 years. In captivity, African grey parrots have a mean lifespan of 45 years, but they can live up to 60 years. In the wild, the average lifespan is 22.7 years (n=120).
Status: captivity: 40 to 60 years.
Status: captivity: 45 years.
Status: wild: 22.7 years.
Status: captivity: 40 to 50 years.
- Ryan, T. 2002. Grit Impaction in Two Neonatal African Grey Parrots (Psittacus erithacus erithacus). Avian Medicine and Surgery, 16: 230-233.
Lifespan, longevity, and ageing
African grey parrots are very social birds. Breeding occurs in loose colonies with each pair occupying its own tree. Individuals select mates carefully and have a lifelong monogamous bond that begins at sexually maturity, at three to five years of age. Few details are known about courtship in the wild, but display flights around nest holes have been observed and recorded. Males feed mates (courtship feeding) and both sing soft monotonous notes. At this time the female will sleep in the nest cavity while the male guards it. In captivity, males feed females after copulation events and both sexes participate in a mating dance in which they droop their wings.
Mating System: monogamous
The breeding season varies by locality, but appears to coincide with the dry season. African grey parrots breed once to twice a year. Females lay three to five roundish eggs, one each at intervals of two to five days. Females incubate the eggs while being fed entirely by the male. Incubation takes approximately thirty days and the young emerge from the nest at twelve weeks old.
Breeding interval: African Grey Parrots breed once to twice a year.
Breeding season: Reproduction appears to coincide with the dry season.
Range eggs per season: 3 to 5.
Average time to hatching: 30 days.
Average fledging age: 12 weeks.
Range time to independence: 2 to 3 years.
Average time to independence: 3 years.
Range age at sexual or reproductive maturity (female): 3 to 5 years.
Range age at sexual or reproductive maturity (male): 3 to 5 years.
Key Reproductive Features: seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate)
After the young emerge from the nest, both parents feed, raise, and protect them. Both parents care for their clutch of young until they reach independence.
Parental Investment: altricial ; pre-fertilization (Provisioning, Protecting: Female); pre-hatching/birth (Provisioning: Female, Protecting: Male, Female); pre-weaning/fledging (Provisioning: Male, Female, Protecting: Male, Female); pre-independence (Provisioning: Male, Female, Protecting: Male, Female); extended period of juvenile learning
- Athan, M. 1999. Barron's Guide to Companion Parrot Behavior. New York, New York: Barron's Educational Series.
- 2006. "African Grey Parrots" (On-line). Accessed April 10, 2008 at Eliteparrotsclub.com/articles/species/mediumsmall/africangreyparrots.html.
- 2008. "Psittacus erithacus (African Grey Parrot, Congo African Grey Parrot, Grey Parrot)" (On-line). Zipcodezoo.com. Accessed March 20, 2008 at http://zipcodezoo.com/Animals/P/Psittacus_erithacus.asp.
- Pepperberg, I. 2001. "Lessons from Cognitive Ethology: Animal Models for Ethological Computing" (On-line pdf). Accessed April 10, 2008 at http://www.lehigh.edu/~mhbo/cogsZwebreadings/Pepperberg23sep01.pdf.
Molecular Biology and Genetics
Barcode data: Psittacus erithacus
No available public DNA sequences.
Download FASTA File
Statistics of barcoding coverage: Psittacus erithacus
Public Records: 2
Specimens with Barcodes: 5
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
Psittacus erithacus is considered to be a near threatened species because of a recent analysis suggesting that up to 21% of the global population may be harvested annually. The quota for African grey parrots in the Democratic Republic of the Congo is 5000, 4000 in Congo, and 250 in Gabon. Unfortunately, there is no law prohibiting capture and trade of parrots. These birds are impacted by habitat destruction, indiscriminate use of pesticides, and hunting by local inhabitants. Trapping for the wild bird trade is a major cause of decline in wild African grey parrots populations.
US Migratory Bird Act: no special status
US Federal List: no special status
CITES: appendix ii
State of Michigan List: no special status
IUCN Red List of Threatened Species: near threatened
- 2008. "CITES species database" (On-line). CITES. Accessed April 14, 2008 at http://www.cites.org/eng/resources/species.html.
- 2008. "The IUCN Red List of Threatened Species" (On-line). Accessed April 15, 2008 at http://www.iuncredlist.org/search/details.php/47991/clss.
Habitat destruction, indiscriminate use of pesticides, and hunting threaten the survival of Gray Parrots. Trapping for the wild bird trade is another major cause of decline in wild populations. A recent study suggests that up to 21% of the global population of Gray Parrots is harvested each year.
As a result of concerns about international trade, P. e. princeps was put on CITES Appendix I in 1975, and the remainder of the species was put on CITES Appendix II with all Psittaciformes in 1981 at the request of Switzerland and Liechtenstein. In 1994, the P. e. princeps CITES listing was removed due to lack of evidence that it is a valid subspecies. Due to concern about the effects of the large numbers of this species traded, it was the subject of a CITES significant trade review, in which it was listed as of "possible concern" (Inskipp et al. 1988). The Animals Committee of CITES recommended a two-year ban from January 2007 in Cameroon. For a further two countries - Congo and the Democratic Republic of Congo - the Committee has recommended that quotas should be halved to 4,000 and 5,000 birds respectively. The species occurs in a number of protected areas. Conservation Actions Proposed
Ensure that proposed trade restrictions are implemented. Monitor wild populations to determine ongoing trends. Consider banning trade in Congo and DRC, as both countries are lacking the necessary capacity to manage it (H. Rainey in litt. 2007). Extend captive breeding efforts to both meet avicultural demands and assist with reintroduction and supplementation efforts.
Relevance to Humans and Ecosystems
Economic Importance for Humans: Negative
There are no known adverse affects of Psittacus erithacus on humans.
Economic Importance for Humans: Positive
African grey parrots are the second most heavily harvested parrot in the world. The trade between 1980 and 1995 documented an excess of 500,000 birds caught in the wild. From 1994 to 2003, just fewer than 360,000 wild caught parrots were reportedly exported from their native range. They are one of the most popular avian pets in Europe, the United States, and the Middle East. In Principe, trappers heavily harvest African grey parrots for the international pet trade.
Positive Impacts: pet trade ; ecotourism ; research and education
- Juste, J. 1995. Trade in the Gray Parrot (Psittacus erithacus) on the Island of Principe (SAO TOME and Principe, Central Africa): Initial Assessment of the Activity on Its Impact. Biological Conservation, 76: 101-104.
- Fahlman, A. 2002. "African Drey Parrot Conservation: a Feasibility evaluation of Developing a Local Conservation Program in Pricipe" (On-line pdf). Accessed April 10, 2008 at http://www.env-impact.geo.uu.se/84Fahlman.pdf.
African Grey Parrot
The African Grey Parrot (Psittacus erithacus), also known as the Grey Parrot, is a parrot found in the primary and secondary rainforest of West and Central Africa. Experts regard it as one of the most intelligent birds in the world. They feed primarily on palm nuts, seeds, fruits, and leafy matter, but have also been observed eating snails. Their overall gentle nature and their inclination and ability to mimic speech have made them popular pets, which has led many to be captured from the wild and sold into the pet trade. The African Grey Parrot is listed on CITES Appendix II, which restricts trade of wild-caught species because wild populations cannot sustain trapping for the pet trade.
Taxonomy and systematics
- Congo African Grey Parrot (Psittacus erithacus erithacus):
This is the nominate subspecies, larger than the Timneh at about 33 cm (13 in) long, with light-grey feathers, cherry-red tails, and an all-black beak. Immature birds of this subspecies have tails with a darker, duller red towards the tip (Juniper and Parr 1999) until their first moult, which occurs by 18 months of age. These birds also initially have grey irises, which change to a pale yellow colour by the time the bird is a year old. The Congo Grey Parrot is found on the islands of Príncipe and Bioko, and is distributed from southeastern Ivory Coast to western Kenya, northwest Tanzania, southern Democratic Republic of the Congo (DRC), and northern Angola. In aviculture, it is often called a "CAG".
- Timneh African Grey Parrot (Psittacus erithacus timneh, or Psittacus timneh):
The Timneh African Grey Parrot is slightly smaller in size than the Congo, but intelligence and talking ability remain comparable. They can range from about 22–28 cm in total length, and are considered a medium size parrot. The Timneh has a darker charcoal grey colouring, a darker maroon tail, and a light, horn-coloured area to part of the upper mandible. Timneh parrots are endemic to the western parts of the moist Upper Guinea forests and bordering savannas of West Africa from Guinea-Bissau, Sierra Leone, and southern Mali east to at least 70 km (43 mi) east of the Bandama River in Ivory Coast. It is often called a "TAG". As pets, Timnehs usually begin learning to speak earlier than Congos as they mature slightly earlier. The Timneh parrot also has a reputation of being less nervous around strangers and novel situations than the Congo, but whether this is true or not is still debated. In 2012, Birdlife International gave the Timneh Parrot full species status and it was classified as Vulnerable.
Some aviculturalists recognize third and fourth subspecies, but these are not distinguishable in scientific studies.
Illness and Disease
The African Grey Parrot (Psittacus erithacus erithacus) has been known at times to contract a non-infectious inflammatory lung disease called Lipid Pneumonia. Lipid Pneumonia can be classified as exogenous or endogenous depending on whether or not the animal inhaled outside material. A necropsy shows that the lungs of a Grey Parrot with Endogenous Lipid Pneumonia (EnLP) are firm with a diffuse grey discoloration. EnLP is a common illness in other animals as well. The Congo African Grey Parrot is also one of the three parrots that scientists found to commonly suffer from dehydration. The Scientists have used Plasma Osmolality to find more information about the form of dehydration the African Grey Parrots have. Another disease that the African Grey Parrots get is cardiomyopathy which is a heart disease usually presented at a young age. The reason for the is from having parents of the same breed. Some other common symptoms in these birds are weakness, coelomic cavity, and retardation. The African Grey Parrot has been known to contract Beak and feather disease virus (BFDV) which causes a highly contagious and sometimes fatal, psittacine beak and feather disease in parrots. In a PCR-based study, Chlamydiosis an infectious disease of avians was found to infect the African Grey Parrot. In the study 253 clinical samples were taken from 27 bird species belonging to seven orders. Thirty-two (12.6%) samples were positive for Chlamydi and two new genotypes were discovered: Chlamydophila psittaci and Chlamydophila abortus. Another ailment that African Grey Parrots commonly suffer from is Hypocalcemic-induced seizure activity. Birds between 2–15 years of age contract it centers around a lack of calcium. A symptom of the syndrome can be unsteadiness while standing or falling off a perch along with neurological anomalies or problems.
Behavior and ecology
Like many large parrots, the African Grey is a long-lived bird. The Animal Ageing and Longevity Database states the longest reliably recorded longevity for the species in captivity as 49.7 years. Also acknowledged are claims of captive African Grey parrots reaching the ages of 73 and 93, whereas the World Parrot Trust lists a longevity of 50–60 years for an African Grey in captivity. The Guinness Book of World Records listed a grey parrot that allegedly lived in captivity for 72 years as the longest-lived specimen for the species.
Birds appear to offer, in their behavior, neurophysiology, and neuroanatomy a striking case of parallel evolution of consciousness. Evidence of near human-like levels of consciousness has been most dramatically observed in African grey parrots.
Unlike other parrots, wild African Greys have been documented imitating the calls of several other species.
Irene Pepperberg's research with captive African Greys, most notably with a bird named Alex, has scientifically demonstrated that African Greys possess the ability to associate simple human words with meanings, and to intelligently apply the abstract concepts of shape, colour, number, zero-sense, etc. According to Pepperberg and other ornithologists, they perform many cognitive tasks at the level of dolphins, chimpanzees, and even human toddlers. However, Pepperberg taught Alex English which suggests that, though they are proficient learners, African Grey Parrots do not have an innate ability to speak. As well as labeling objects, Alex could express what his wants were, suggesting that African Grey parrots know the difference between features and feelings. In general, it has been shown that African Grey Parrots are able to learn relatively quickly, though they are limited to simple and non-abstract mediums of thinking. They have been shown to be able to make cognitive inferences, but, like apes, have inter-individual differences in intelligence. For example, in one experiment involving food hidden under cups, it was shown that African Greys can identify where the food is, usually if shown its original location at first.
Many pet Congo African Greys learn to speak in their second or third year. Timnehs are generally observed to start speaking earlier, some in their late first year. Both subspecies seem to have the same ability and tendency to produce human speech, but vocal ability and proclivity may range widely among individual birds. The African Grey Parrots tend to use more specific calls for different species coming their way which can be known as Stimulus Specificity, since there is a stimulus vocalization the birds have. One notable African Grey is N'kisi, which in 2004 was said to have a vocabulary of over 950 words and, like Pepperberg's Alex, was noted for creative use of language. For example, when Jane Goodall visited N'kisi in his New York home, he greeted her with "Got a chimp?" because he had seen pictures of her with chimpanzees in Africa.
A study published in 2011, led by Dalila Bovet of Paris West University Nanterre La Défense, demonstrated African Grey parrots were able to coordinate and collaborate with each other to an extent. They were able to solve problems set by scientists—for example, two birds could pull strings at the same time to obtain food. In another example, one bird stood on a perch to release a food-laden tray, while the other pulled the tray out from the test apparatus. Both would then feed. The birds in question were observed waiting for their partners to perform the necessary actions so their behaviour could be synchronized. The parrots appeared to express individual preferences as to which of the other test birds they would work with.
In an experiment about local enhancement in Grey Parrots, food was visibly hidden under two separate cups. The experimenter then lifted the first cup and either removed what was under it or put it back. This was then done again in several different combinations, the cups were lifted in a different order and the food was removed or put back in a different order. Instead of remembering which cup had the food, the birds would show preference to the one that was touched last. 
Another series of experiments further tested African Grey Parrots' cognitive abilities. In general, most animals cannot associate sounds with objects, such as food, placed into a cup. While originally only the great apes and young human children were known to make this association with ease, it was found that African Grey Parrots, under most conditions, can also associate sounds with the presence of an object. For the most part, Grey Parrots performed more successfully if the cup was shaken horizontally before it is given the choice of selecting which contained food, however, further experimentation indicated that it is not a requirement and proved that Grey Parrots have very high cognitive abilities.
Wild African Grey Parrots often whistle, click, or make other sounds. An African Grey's owner should expect to hear regular renditions of microwaves, telephones, alarm clocks, video games, and other electronic sounds, as well as dripping water, wild birds, and any other sound often heard by the parrot. African Greys have even been known to repeat the profanity they heard from an owner even after they no longer live with that owner. African Greys also have the ability to mimic, and distinguish between, the different voices they hear. The African Grey parrots use different alarm calls for different predators coming their way.
In an experiment to test the vocalizations of Grey Parrots, 4 bred in captivity were placed in an aviary. Throughout the day they spent time in a room with toys and came into fairly regular contact with the humans taking care of them. The noises that these parrots could hear consisted of the calls of canaries in the laboratory, people cleaning, doors squeaking, etc. In the next 3 years, the parrots made over 50,000 vocalisations. What was interesting was that, although they were bred in captivity, the sounds they made were not only ones of their immediate surroundings. They also made calls similar to those of other captive grey parrots in different locations and even wild grey parrots.
Status and conservation
More rare than previously believed, the African Grey was uplisted from a species of Least Concern to Near Threatened in the 2007 IUCN Red List. A recent analysis suggests up to 21% of the global population may be taken from the wild annually, primarily for the pet trade. In 2012, the species was further uplisted to Vulnerable.
The species is endemic to primary and secondary rainforests of West and Central Africa. Grey parrots depend on large, old trees for the natural hollows they use for nesting. Studies in Guinea and Guinea-Bissau have found that African Greys' preferred species of nesting trees are also species preferred for timber. The relationship between the status of the species and the status of primary forest is positive: where the forests are declining, so too are populations of grey parrots.
The African Grey Parrot is listed on Appendix II of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES). This requires both that exports be accompanied by a permit issued by a national authority and that a finding be made that the export is not detrimental to the species in the wild. With exports totalling more than 350,000 specimens from 1994–2003, the grey parrot is one of the most heavily traded CITES-listed bird species. In response to continuing population declines, exceeded quotas, and unsustainable and illegal trade (including among range states), CITES included the grey parrot in Phase VI of the CITES Review of Significant Trade in 2004. This review has resulted in recommended zero export quotas for several range states and a CITES decision to develop regional management plans for the species.
In the United States, importation of wild-caught grey parrots is prohibited under the US Wild Bird Conservation Act of 1992. In the European Union, an EU Directive of 2007 prevents importation of this and any other wild-caught birds for the pet trade.
Relationship with humans
Their sociability and intelligence can make African Grey Parrots excellent pets. They have a devoted following among parrot owners. However, the same qualities mean African Greys require a special commitment by their owners to provide frequent one-on-one interaction and supervised time out of their cages. They must be kept entertained and busy with people and toys or they may become stressed and develop self-destructive behaviors. African Greys require large cages, varied diets that include fresh foods, and plenty of safe and destructible toys. If not provided with these items, African Greys quickly develop unpleasant behaviours and may eventually develop health problems (such as feather-plucking) that are difficult to remedy.
Even the healthiest, happiest pet African Grey will generate a fair amount of mess and noise. Like most parrots, they are not domesticated, and even a well-socialized, hand-raised, aviary-bred bird is only one or two generations removed from its wild predecessor. Despite this, the recorded history is long of African Greys being kept by the ancient Greeks, wealthy Roman families, King Henry VIII, Portuguese sailors, and others.
- The character 'Gerard' in Michael Crichton's novel Next is a transgenic African Grey with the capability of doing math.
- The character 'Madison' in Dick King-Smith's novel Harry's Mad is an African Grey parrot.
- The character 'Methuselah' in Barbara Kingsolver's novel The Poisonwood Bible is an African Grey parrot.
- The children's book Friendly Feathers: Life with Pierre, an African Grey Parrot by Fran Smith, illustrated by Deon Matzen, is about an African Grey parrot. ISBN 978-0-615-22232-5
- The bird owned by the character 'Linus Steinman' in the novel The Final Solution by Michael Chabon is an African Grey.
- In the book, We'll Always Have Parrots by Donna Andrews, an African Grey Parrot helps protagonist Meg Langslow apprehend the antagonist.
- In the book, Sick as a Parrot by Liz Evans, the parrot in the title is an African Grey.
- Cat Marsala, the main protagonist in "Hard Christmas" by Barbara D'Amato, has a pet African Grey parrot named Long John Silver.
- In the book Somebody Else's Summer, Bilbo was an African Grey Parrot which belonged to George Carr.
- The character 'Polynesia' in Hugh Lofting's Doctor Dolittle children's novels is an African Grey Parrot. In the film version, the character was played by a Blue and Gold Macaw.
- In Thomas Bernhard's play Immanuel Kant, the philosopher praises his Psittacus eritacus without end, saying only he understands his logic.
- Mercedes Lackey's short stories "Grey" and "Grey's Ghost" feature an African Grey Parrot that has a remarkable bond with her owner.
- Web Comic Matthew Inman; also known as "The Oatmeal", wrote a web comic about his pet African Grey http://theoatmeal.com/comics/grump
- Online Parrot Personality "Felix" through who's subtitled life parrot advocacy is shared. http://www.facebook.com/felixlafollett. Felix is also featured in 3 books promoting proper companion parrot communication and understanding by author Kathy LaFollett. http://www.blurb.com/b/4361582-book-of-felix
- Forshaw & Cooper (1978).
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- "Longevity, ageing, and life history of Psittacus erithacus". The Animal Ageing and Longevity Database. Retrieved 7 September 2011.
- "Grey Parrot (Psittacus erithacus) | Parrot Care". World Parrot Trust. Retrieved 7 September 2011.
- Wood, Gerald (1983). The Guinness Book of Animal Facts and Feats. ISBN 978-0-85112-235-9.
- The Cambridge Declaration on Consciousness (Archive) 7 July 2012. Written by Philip Low and edited by Jaak Panksepp, Diana Reiss, David Edelman, Bruno Van Swinderen, Philip Low and Christof Koch. University of Cambridge.
- "Stray Japan parrot talks way home". BBC News. 22 May 2008. Archived from the original on 2 April 2010. Retrieved 23 April 2010.
- Kaufman, Allison; et. al (September 2013). "Higher-order semantic structures in an African Grey parrot's vocalizations: evidence from the hyperspace analog to language (HAL) model". Animal Cognition 16 (5): 789–801/10.1007/s10071–013–0613–3.
- Sukova, K; et. al. (June 2013). "Abstract concept formation in African grey parrots (Psittacus erithacus) on the basis of a low number of cues". Behavioral Processes 96: 36–41.
- Mikolasch, Sandra; et. al. (Dec 2011). "African grey parrots (Psittacus erithacus) use inference by exclusion to find hidden food". Biology Letters 7 (6): 875–877.
- Deter, Dianalee (2000). The African Grey Parrot Handbook. Hauppauge, New York: Barron's. ISBN 0-7641-4140-6.
- Giret, Nicolas; et.al (Apr 2012). "Context-related vocalizations in African grey parrots (Psittacus erithacus)". ACTA ETHOLOGICA 15 (1): 39–46. doi:10.1007/s10211-011-0106-9.
- Nkisi Audio Text 1
- Gill, Victoria. "Parrots choose to work together". BBC Nature News. Archived from the original on 20 May 2011. Retrieved 19 May 2011.
- Mikolasch, Sandra; Kotrschal, Schloegl, (November 2012). "The Influence of Local Enhancement on Choice Performances in African Grey Parrots (Psittacus erithacus) and Jackdaws (Corvus monedula)". Journal of Comparative Psychology 126 (4): 399–406. doi:10.1037/a0028209.
- Schloegl, Christian; et. al. (22 OCT 2012). "Grey parrots use inferential reasoning based on acoustic cues alone". Proceedings of the Royal Society B 279 (1745): 4135–4142. doi:10.1098/rspb.2012.1292.
- Giret, Nicolas; et. al (April 2012). "Context-related vocalizations in African grey parrots (Psittacus erithacus)". ACTA ETHOLOGICA 15 (1): 39–46. doi:10.1007/s10211-011-0106-9.
- Giret, Nicholas; Albert, Nagle, Kreutzer, Bovet (April 2012). "Context-related vocalizations in African grey parrots (Psittacus erithacus)". ACTA ETHOLOGICA 15 (1): 39–46. doi:10.1007/s10211-011-0106-9.
- See BirdLife International (2007a. b).
- See Juniper, T. and M. Parr. 1998. Parrots: A Guide to Parrots of the World. Yale University Press, New Haven and London.
- See Clemmons, J.R. 2003. Status Survey of the African Grey Parrot (Psittacus erithacus timneh) and Development of a Management Program in Guinea and Guinea-Bissau. CITES, Geneva, Switzerland.
- Dändliker, G. 1992. The Grey Parrot in Ghana: A population survey, a contribution to the biology of the species, a study of its commercial exploitation and management recommendations. CITES, Lausanne, Switzerland.
- See UNEP-WCMC CITES Trade Database.
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- The IUCN Red List of Threatened Species: Psittacus erithacus (Retrieved 6 July 2011)
- BirdLife International (2007a): [ 2006–2007 Red List status changes ]. Retrieved 26 August 2007.
- BirdLife International (2007b): Grey Parrot – BirdLife Species Factsheet. Retrieved 26 August 2007.
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- Schmid, R. Doherr, M G. Steiger, The influence of the breeding method on the behaviour of adult African grey parrots (Psittacus erithacus). Applied Animal Behaviour Science 2005, see www.elsevier.com/locate/applanim
- Linnaeus, Carolus (1758): Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. (10th edition, vol.1). Laurentius Salvius, Holmia (= Stockholm).
- Mancini, Julie R. (1998): The African Grey. Howell Book House, New York. ISBN 0-87605-443-2
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