Overview

Brief Summary

Biology

The African grey parrot feeds on a variety of fruits, seeds and nuts, particularly those of the oil-palm, Elaeis guineensis. It is also known to do damage to maize crops (3) (8). The species can travel considerable distances in search of fruiting trees (3), and may also make seasonal movements out of the driest parts of its range during the dry season (2). The African grey parrot often roosts in large groups, and forms large, noisy flocks, the birds calling to each other with a variety of squawks, whistles, shrieks and screams, both at rest and in flight (7). In addition to its ability to mimic human speech, this parrot has also been found to mimic other bird and mammal calls in the wild (12). Nests are generally a simple cavity, high in a tree (3). Usually, two to three eggs are laid, and hatch after an incubation of between 21 and 30 days, the young leaving the nest around 80 days later (3). Captive individuals may live up to 50 years (13). In recent years, research on a captive African grey parrot known as 'Alex' has highlighted the impressive intelligence of this species. As well as learning the names of over 50 objects, Alex was able to use English words to identify colours, shapes and quantities up to six, as well as to demonstrate an understanding of concepts such as bigger / smaller, same / different, and absence, and to use words and phrases to make simple requests. Such studies suggest that the intelligence of African grey parrots is comparable to that of marine mammals, apes and even young children (14).
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Description

Famous for its intelligence and ability to mimic human speech, the African grey parrot is one of the most popular of all avian pets (2). One of the largest parrots in Africa (5), the plumage is pale grey, with whitish edges to the feathers on the head and neck, which give a lacy or 'scalloped' appearance. The flight feathers are darker grey, the rump pale and the short tail a striking red. The beak is black, and on the face a large area of bare white skin surrounds the pale yellow eye (3) (6) (7). Both males and females are similar in appearance, while juveniles can be recognised by a dark grey or black eye, grey-tinged undertail-coverts and a darker red tip to the tail (6) (7). Two subspecies are currently recognised: Psittacus erithacus erithacus, sometimes known as the red-tailed African grey parrot or the Congo African grey parrot, and Psittacus erithacus timneh, also known as the Timneh African grey parrot (2) (8) (9). P. e. timneh is smaller, with darker plumage, a dark maroon rather than red tail, red on the upper part of the beak and a distinctive call (2) (6) (7). There is thought to be very little interbreeding between the two subspecies, and some would prefer to have them classed as separate species (3) (10). A separate population of African grey parrots on the island of Príncipe in the Gulf of Guinea was previously considered a third subspecies, Psittacus erithacus princeps, but is now included with P. e. erithacus (4) (11).
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Comprehensive Description

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.

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Distribution

Range Description

Psittacus erithacus has been split into P. timneh and P. erithacus. P. erithacus has a distribution extending from southeastern Côte d'Ivoire east through the moist lowland forests of West Africa to Cameroon, and thence in the Congo forests to just east of the Albertine Rift (up to the shores of Lake Victoria) in Uganda and Kenya and south to northern Angola (Juniper and Parr 1998), as well as on the islands of Principe (Sao Tomé and Principe) and Bioko (Equatorial Guinea). Preliminary calculations based on forest cover and country-level population estimates (Dändliker 1992a, 1992b, Collar 1997, Fotso 1998b, JRC 2000), subtracting estimates for P. timneh, suggest a global population of between 560,000 and 12.7 million individuals (Pilgrim et al. in prep.). Population declines have been noted in Burundi, Cameroon, Ghana, Kenya, Nigeria, Rwanda, São Tomé and Príncipe, Togo, Uganda and parts of Congo and the Democratic Republic of the Congo. In all of these declines, trapping for the wild bird trade has been implicated, with habitat loss also having significant impacts throughout West and East Africa. From 1982 to 2001, over 657,000 wild-caught individuals of erithacus and timneh (the vast majority erithacus) entered international trade (UNEP-WCMC 2003). Considering estimates for pre-export mortality, the number of birds extracted from the wild during this period may well have numbered over 1 million (A. Michels in litt. 2012). Cameroon accounted for 48% of exports from 1990-1996 (Waugh 2010), and estimates that c90% of trapped birds died before reaching Douala airport suggest, although quotas remained at 12,000, over 100,000 birds were being captured in Cameroon annually during this period (F. Dowsett-Lemaire in litt. 2012).
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Geographic Range

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.
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Range

The species has a wide distribution across tropical Africa, from Guinea-Bissau east to Kenya and Tanzania, and south to Angola (2), including populations on the islands of Príncipe and São Tomé (3). P. e. timneh is restricted to the western part of this range, from Guinea to Ivory Coast, with isolated populations in Guinea-Bissau and southern Mali (3) (6).
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Physical Description

Morphology

Physical Description

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

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Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
Although typically inhabiting dense forest, they are commonly observed at forest edges, clearings, gallery forest, mangroves, wooded savannah, cultivated areas, and even gardens (Juniper and Parr 1998), but it is not clear whether these are self-sustaining populations. At least in West Africa, the species makes seasonal movements out of the driest parts of the range in the dry season. It is highly gregarious, forming large roosts at least historically containing up to 10,000 individuals (Juniper and Parr 1998). Feeding takes place in smaller groups of up to 30 birds and the diet consists of a variety of fruits and seeds, while the nest is in a tree cavity 10-30 m above ground (Juniper and Parr 1998). Nesting is usually solitary, but can take place in loose colonies, for example in Principe, while the breeding season varies across the range (Juniper and Parr 1998).


Systems
  • Terrestrial
  • Freshwater
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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

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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.

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Lowland moist forest, both primary and secondary; also observed at forest edges and clearings, and sometimes mangrove forest, gallery forest, savanna woodland and in cultivated areas. The African grey parrot is often found in areas of oil-palms (Elaeis guineensis), on which it likes to feed, and commonly roosts in raphia palms overhanging watercourses, or on offshore islands (2) (3).
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Trophic Strategy

Food Habits

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

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Associations

Ecosystem Roles

African grey parrots may disperse the seeds of fruits they eat. They act as definitive hosts to both tapeworms and blood parasites.

Commensal/Parasitic Species:

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Predation

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.

Known Predators:

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Life History and Behavior

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.
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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.

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Life Expectancy

Lifespan/Longevity

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).

Range lifespan

Status: captivity:
40 to 60 years.

Average lifespan

Status: captivity:
45 years.

Average lifespan

Status: wild:
22.7 years.

Typical lifespan

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.
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Lifespan, longevity, and ageing

Maximum longevity: 49.7 years (captivity) Observations: There are claims of animals living 73 and 93 years (Flower 1938). The most reliable longevity record, however, is a specimen that was still alive after 49.7 years (Brouwer et al. 2000).
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Reproduction

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.
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Molecular Biology and Genetics

Molecular Biology

Barcode data: Psittacus erithacus

The following is a representative barcode sequence, the centroid of all available sequences for this species.


No available public DNA sequences.

Download FASTA File
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Statistics of barcoding coverage: Psittacus erithacus

Barcode of Life Data Systems (BOLDS) Stats
Public Records: 2
Specimens with Barcodes: 5
Species With Barcodes: 1
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Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
VU
Vulnerable

Red List Criteria
A2abcd+3bcd+4abcd

Version
3.1

Year Assessed
2013

Assessor/s
BirdLife International

Reviewer/s
Butchart, S.

Contributor/s
Bellamy, D., Boyes, S., Dowsett-Lemaire, F., Gilardi, J., Hall, P., Hart, J., Hart, T., Lindsell, J., Michels, A., Phalan, B., Pomeroy, D. & Rainey, H.

Justification
This species has been uplisted to Vulnerable because the extent of the annual harvest for international trade, in combination with the rate of ongoing habitat loss, means it is now suspected to be undergoing rapid declines over three generations (47 years).


History
  • 2012
    Vulnerable
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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

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Status

Classified as Near Threatened (NT) on the IUCN Red List (1) and listed on Appendix II of CITES (4).
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Population

Population
Gatter (1997) estimated two breeding pairs/ km2 of P. timneh in logged forest north of Zwedru, Liberia. McGowan (2001) provided similar estimates of nest densities in Nigeria of 0.5-2.1/km2, believing the higher end to be more accurate. This would indicate 4.2 breeding birds/km2 plus non-breeding birds (the remaining 70-85% of the population, as estimated by Fotso (1998b), giving estimates of 4.9-6.0 birds/km2. These estimates are substantially higher than those of 0.3-0.5 birds/km2 in good habitat in Guinea (timneh) and 0.9-2.2 birds/km2 (in evergreen forests) or 0.15-0.45 birds/km2 (in semi-deciduous forests) in Ghana. Using these density estimates, the overall P. timneh population was estimated at 120,100-259,000 birds, and the West African population of P. erithacus at 40,000-100,000 birds, although central African populations of this subspecies are much larger. Using a global land cover classification, a digitised map of the species's range from Benson et al. (1988), and estimates of density 0.15-0.45 birds/km2 in semi-deciduous forest (including deciduous forest) and 0.3-6.0 birds/km2 in evergreen forest (including swamp forest and mangrove), supplemented by post-1995 published national estimates where available, an initial coarse assessment of the global population of this species (subtracting estimates for the now-split P. timneh) is 0.56-12.7 million individuals.

Population Trend
Decreasing
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Threats

Major Threats
It is one of the most popular avian pets in Europe, the United States, and the Middle East due to its longevity and unparalleled ability to mimic human speech and other sounds. Demand for wild birds is also increasing in China, and increased presence of Chinese businesses in central Africa (particularly for mining, oil and logging) may increase illegal exports of this species (F. Maisels in litt. 2006, H. Rainey in litt. 2006). From 1982 to 2001, over 657,000 wild-caught individuals of both erithacus and timneh (the vast majority erithacus) entered international trade (UNEP-WCMC 2005). Considering estimates for pre-export mortality, the number of birds extracted from the wild during this period may well have numbered over 1 million (A. Michels in litt. 2012). In the late 1990s and early 2000s Cameroon exported an annual quota of 10,000 birds; estimates that c90% of trapped birds died before reaching Douala airport suggest that some 100,000 birds per year were being captured in Cameroon during that period (F. Dowsett-Lemaire in litt. 2012). Official statistics give exports of 367,166 individuals from Cameroon in the period 1981-2005, and the country accounted for 48% of exports between 1990-1996 (Waugh 2010). Up to 10,000 wild-caught birds from the Democratic Republic of the Congo are apparently imported into South Africa each year (S. Boyes in litt. 2011). Because it concentrates in traditional roosting, drinking and mineral lick sites, it is especially vulnerable to trapping pressure. Habitat loss is undoubtedly having significant impacts, particularly throughout West and East Africa. In addition to capture for international trade, there is an active internal trade in live birds for pets and exhibition (McGowan 2001, Clemmons 2003, A. Michels in litt. 2012). The species is also hunted in parts of the range as bushmeat and to supply heads, legs and tail feathers for use as medicine or in black magic (Fotso 1998, McGowan 2001, Clemmons 2003, A. Michels in litt. 2012).

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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.

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Habitat loss (particularly the loss of large nesting trees) is likely to be having a significant impact on African grey parrot populations. However, the main threat is the capture of large numbers of wild individuals for the international pet trade (2) (10). Estimates suggest that up to a fifth of the global population may be harvested annually to be sold as pets, though actual numbers captured are likely to be higher than those officially recorded, due to the number of birds that die during capture or transport, and due to illegal trade (2) (10). Worryingly, there also appears to be an increasing market for parrot heads and tail feathers, which are being harvested for purported medicinal purposes, and which are more easily stored and transported than live birds (15).
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Management

Conservation Actions

Conservation Actions
Conservation Actions Underway
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.

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Conservation

The African grey parrot is still numerous and found over a wide range, and occurs in a number of protected areas such as Salonga National Park in the Democratic Republic of Congo, a World Heritage Site and the largest tropical rainforest reserve in Africa, although political instability here makes protection difficult (16). However, despite trade being monitored to some extent under the Convention on International Trade in Endangered Species (CITES) (4), current levels are considered unsustainable and the African grey parrot is now in decline (2) (10). Conservation measures proposed include reducing quotas and banning exports from some countries, as well as attempting tighter control of trade and increased monitoring and research (2) (10). BirdLife International have recommended that the subspecies be treated separately in terms of their status and conservation, particularly considering the greater scarcity of P. e. timneh (10), while others also suggest that the population on Príncipe, which is heavily harvested, should also be treated separately (11). Conservation of this isolated, and perhaps unique, population should be aided by the fact that it is the symbol of the island (11). The import of wild-caught African grey parrots is now banned in the USA under the Wild Bird Conservation Act of 1992, and in Europe under the EU Birds Directive of 2007 (9), and this may further help to decrease the level of trade in this highly intelligent bird. However, more research may now be needed into the trade in parrot heads and feathers if this emerging threat is to be effectively countered (15).
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Relevance to Humans and Ecosystems

Benefits

Economic Importance for Humans: Negative

There are no known adverse affects of Psittacus erithacus on humans.

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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.
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Wikipedia

African grey parrot

The African Grey Parrot, grey parrot or Congo African Grey Parrot (Psittacus erithacus) is an Old World parrot in the family Psittacidae.

Description[edit]

The African Grey Parrot is a medium-sized, predominantly grey, black-billed parrot which weighs 400 g, with a length of 33 cm[1] and an average wingspan of 46–52 cm.[2] The tail and undertail coverts are red, in comparison to the maroon of the smaller Timneh Parrot. Both sexes appear similar.[1]

The colouration of juveniles similar to that of adults, however the eye is typically dark grey to black, in comparison to the greyish eyes of the adult birds. The undertail coverts are also tinged with grey.[1]

Distribution and habitat[edit]

The African Grey Parrot is endemic to the Congo, Africa.

Behaviour and ecology[edit]

Breeding[edit]

African grey parrots are monogamous breeders which nests in tree cavities. The hen lays 3-5 eggs, which she incubates for 30 days while being fed by her mate. Young leave the nest at the age of 12 weeks. Little is known about the courtship behaviour of this species in the wild.[2]

Food and feeding[edit]

The African grey parrot is primarily a herbivore, feeding on fruit, nuts, leaves, bark and flowers. However it will also eat insects.[2]

Threats to survival[edit]

Humans are by far the largest threat to wild African grey populations. Between 1994 and 2003, over 359,000 African grey parrots were traded on the international market. Mortality amongst imported birds is high.[3] As a result of the extensive harvest of wild birds, in addition to habitat loss, this species is believed to be undergoing a rapid decline in the wild and has therefore been rated as vulnerable by the IUCN.[4]

Relationship to humans[edit]

The species is common in captivity and is regularly kept by humans as a companion parrot, prized for its ability to mimic human speech. However, it may be prone to behavioural problems due to its sensitive nature.[3]

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African Grey Parrot

Psittacus is a genus of African parrots in the subfamily Psittacinae. It contains the two species; the Congo African Grey Parrot (Psittacus erithacus) and the Timneh African Grey Parrot (Psittacus timneh).

For many years, the Congo African Grey Parrot and Timneh African Grey Parrot were classified as subspecies; the former as the nominate the latter as P. e. timneh. However in 2012 the taxa were recognized as separate species by BirdLife International on the basis of genetic, morphological, plumage and vocal differences.[1][2]

These parrots are found in the primary and secondary rainforest of West and Central Africa. They are 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 inclination and ability to mimic speech and other sounds have made them popular pets.

Taxonomy and systematics[edit]

Two species are accepted:[3]

  • African Grey Parrot, Grey Parrot or Congo African Grey Parrot (Psittacus erithacus, previously 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.[3] 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 Parrot or Timneh African Grey Parrot (Psittacus timneh, previously Psittacus erithacus 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[4] and it was classified as Vulnerable.[5]

Some aviculturalists recognize third and fourth subspecies, but these are not distinguishable in scientific studies.[6]

Illness and Disease[edit]

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.[7] 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.[8] 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.[9] 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.[10] 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.[11] 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.[12]

Behavior and ecology[edit]

Breeding[edit]

The African Grey Parrots are monogamous breeders which nests in tree cavities. The hen lays 3-5 eggs, which she incubates for 30 days while being fed by her mate. Young leave the nest at the age of 12 weeks. Little is known about the courtship behaviour of this species in the wild.[13]

Longevity[edit]

Like many large parrots, African Greys are long-lived birds. 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,[14] whereas the World Parrot Trust lists a longevity of 50–60 years for an African Grey in captivity.[15] 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.[16]

Intelligence[edit]

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.[citation needed]

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.[18] As well as labeling objects, Alex could express what his wants were, suggesting that African Grey parrots know the difference between features and feelings.[19] 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.[20] 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.[21]

Pet Congo African Greys may learn to speak within their first year, but many don't say their first word until 12–18 months old.[22] Timnehs are generally observed to start speaking earlier, some in their late first year.[23] 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.[24] 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.[25] 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.[26]

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.[27]

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. [28]

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.[29]

Noises[edit]

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.[30]

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.[31]

Status and conservation[edit]

Timneh African Grey Parrot (wings clipped)

More rare than previously believed, the Congo African Grey was uplisted from a species of Least Concern to Near Threatened in the 2007 IUCN Red List.[32] A recent analysis suggests up to 21% of the global population may be taken from the wild annually,[32] primarily for the pet trade. In 2012, the species was further uplisted to Vulnerable.[5] As they are good in talking The species is endemic to primary and secondary rainforests of West and Central Africa.[33] 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.[34] The relationship between the status of the species and the status of primary forest is positive:[35] where the forests are declining, so too are populations of grey parrots.[34]

Congo African Grey Parrot in a bird park

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,[36] 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[edit]

Aviculture[edit]

A pet Congo African Grey Parrot

These intelligent mimics can make interesting pets and companion parrots. They have a devoted following among parrot owners. However, the same qualities mean they 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 stimulated and busy by 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 chewable toys. If not provided with these items, these parrots can quickly develop unpleasant behaviours and may eventually develop health problems (such as feather-plucking) that are difficult to remedy.

Even the healthiest, happiest pet parrot 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 usually only one or two generations removed from its wild predecessor. Despite this, there is a long history of these parrots being kept at pets by the ancient Greeks, wealthy Roman families, King Henry VIII, Portuguese sailors, and others.

Cultural depictions[edit]

  • 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

See also[edit]

References[edit]

Footnotes[edit]

  1. ^ "Grey Parrot (Psittacus erithacus) has been split into Grey Parrot (P. erithacus) and Timneh Grey Parrot (P. timneh): are both eligible for uplisting?". Birdlife International (2011). Retrieved 27 March 2014. 
  2. ^ "Trade in Africa’s Grey Parrots and Timneh Parrots is currently not sustainable". BirdLife International. Retrieved 27 March 2014. 
  3. ^ a b Forshaw & Cooper (1978).
  4. ^ "Grey Parrot (Psittacus erithacus) has been split into Grey Parrot (P. erithacus) and Timneh Grey Parrot (P. timneh): are both eligible for uplisting?". Birdlife International (2011). Retrieved 18 June 2012. 
  5. ^ a b "Recently recategorised species". Birdlife International (2012). Retrieved 18 June 2012. 
  6. ^ Jean Pattison (2006). "An Introduction and Overview of the African Species". Wings Central. Wings Computer Consulting Inc. Archived from the original on 28 October 2007. Retrieved 26 November 2007. 
  7. ^ Costa, T; et. al (Aug–Oct 2013). "Endogenous Lipid Pneumonia in an African Grey Parrot (Psittacus erithacus erithacus)". JOURNAL OF COMPARATIVE PATHOLOGY 149 (2-3): 381–384. 
  8. ^ Beaufrere, Hugues; et. al (June 2011). ": Plasma Osmolality Reference Values in African Grey Parrots (Psittacus erithacus erithacus), Hispaniolan Amazon Parrots (Amazona ventralis), and Red-fronted Macaws (Ara rubrogenys)". JOURNAL OF AVIAN MEDICINE AND SURGERY 25 (2): 91–96. 
  9. ^ Juan-Salles, c; et. al (May 2011). "Congestive Heart Failure in 6 African Grey Parrots (Psittacus e erithacus)". VETERINARY PATHOLOGY 48 (3): 691–697. doi:10.1177/0300985810377071. 
  10. ^ Julian, Laurel (2013). "Extensive recombination detected among beak and feather disease virus isolates from breeding facilities in Poland". JOURNAL OF GENERAL VIROLOGY 94: 1086–1095. doi:10.1099/vir.0.050179-0. 
  11. ^ Madani; Peighambari (Feb 2013). AVIAN PATHOLOGY 42 (1): 38–44. doi:10.1080/03079457.2012.757288. 
  12. ^ Kirchgessner, Megan; Tully, Nevarez, Guzman (March 2012). "Magnesium Therapy in a Hypocalcemic African Grey Parrot (Psittacus erithacus)". JOURNAL OF AVIAN MEDICINE AND SURGERY 26 (1): 17–21. 
  13. ^ Holman, Rachel. "Psittacus erithacus". Animal Diversity Web. Retrieved 18 March 2014. 
  14. ^ "Longevity, ageing, and life history of Psittacus erithacus". The Animal Ageing and Longevity Database. Retrieved 7 September 2011. 
  15. ^ "Grey Parrot (Psittacus erithacus) | Parrot Care". World Parrot Trust. Retrieved 7 September 2011. 
  16. ^ Wood, Gerald (1983). The Guinness Book of Animal Facts and Feats. ISBN 978-0-85112-235-9. 
  17. ^ 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.
  18. ^ "Stray Japan parrot talks way home". BBC News. 22 May 2008. Archived from the original on 2 April 2010. Retrieved 23 April 2010. 
  19. ^ 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. 
  20. ^ 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. 
  21. ^ 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. 
  22. ^ Bono, Lisa. "African Grey Parrots: Myths & Facts". birdchannel.com. Retrieved 2014-03-17. 
  23. ^ Deter, Dianalee (2000). The African Grey Parrot Handbook. Hauppauge, New York: Barron's. ISBN 0-7641-4140-6. 
  24. ^ 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. 
  25. ^ Nkisi Audio Text 1
  26. ^ [1]
  27. ^ Gill, Victoria. "Parrots choose to work together". BBC Nature News. Archived from the original on 20 May 2011. Retrieved 19 May 2011. 
  28. ^ 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. 
  29. ^ 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. 
  30. ^ 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. 
  31. ^ 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. 
  32. ^ a b See BirdLife International (2007a. b).
  33. ^ See Juniper, T. and M. Parr. 1998. Parrots: A Guide to Parrots of the World. Yale University Press, New Haven and London.
  34. ^ a b 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.
  35. ^ 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.
  36. ^ See UNEP-WCMC CITES Trade Database.

Sources[edit]

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