Psittacus erithacusgrey parrot

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. (Melo and O'Ryan, 2007)

Habitat

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. ("Psittacus erithacus, Linnaeeus, 1758", 2008; Athan and Deter, 2000; Melo and O'Ryan, 2007)

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. (Athan and Deter, 2000; Melo and O'Ryan, 2007)

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. (Athan and Deter, 2000; Melo and O'Ryan, 2007)

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 (Athan and Deter, 2000; Melo and O'Ryan, 2007)

  • Sexual Dimorphism
  • sexes colored or patterned differently
  • Average mass
    407 g
    14.34 oz
  • Average length
    33 cm
    12.99 in
  • Range wingspan
    18 to 20 cm
    7.09 to 7.87 in

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. ("African Grey Parrots", 2006; "Psittacus erithacus (African Grey Parrot, Congo African Grey Parrot, Grey Parrot)", 2008; Athan, 1999; Pepperberg, 2001)

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. ("African Grey Parrots", 2006; "Psittacus erithacus (African Grey Parrot, Congo African Grey Parrot, Grey Parrot)", 2008; Athan, 1999; Pepperberg, 2001)

  • 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

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. ("African Grey Parrots", 2006; "Psittacus erithacus (African Grey Parrot, Congo African Grey Parrot, Grey Parrot)", 2008; Athan, 1999; Pepperberg, 2001)

  • 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

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). ("African Grey Parrots", 2006; "Psittacus erithacus, Linnaeeus, 1758", 2008; Ryan, 2002)

  • 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

Behavior

Wild African grey parrots are very shy and rarely allow humans to approach them. They are highly social and nest in large groups, although family groups occupy their own nesting tree. They are often observed roosting in large, noisy flocks calling loudly during mornings and evenings and in flight. These flocks are composed of only African grey parrots, unlike other parrots that are often found in mixed flocks. During the day, they break into smaller flocks and fly long distances to forage. They often roost in trees over water and are said to prefer roosting on islands in rivers. Young birds stay with their family groups for a long period of time, up to several years. They socialize with others of their age in nursery trees, but remain in their family group within the larger flock. Young African grey parrots are cared for by older birds until they are educated enough and old enough to become independent flock members. Young exhibit appeasement behaviors towards older members. As they mature, birds become more aggressive with conspecifics. African grey parrots in the wild must learn a complex set of skills. They need to learn how to separate desirable food plants from toxic plants, how to defend territory, how to recognize and avoid predators, how to find safe water, and how to rejoin their families when separated. Also, they must learn how to develop role-appropriate behaviors such as competing and defending nest sites and raising offspring. Competition for nest holes during mating season makes the species extremely aggressive. Because African grey parrots are partial ground feeders, there is a series of behavioral events that occur before landing and safe consumption takes place. Groups of parrots gather at a barren tree until it is completely filled with hundreds of birds that partake in preening, climbing, vocalizing, and socializing. Eventually the birds make their way down to the ground in waves with the entire group never being on the ground at the same time. Once on the ground, they are extremely vigilant, reacting to any movement and/or sound. ("African Grey Parrots", 2006; Athan and Deter, 2000; Athan, 1999; Galef, 2004; Luescher, 2006; Wright, 2002)

Studies have found that African grey parrots have complex cognition and are considered one of the most intelligent species of animal. They test and form ideas about the world. In a study preformed by Irene Pepperberg (2007), African grey parrots were tested on insightful behavior and imitative competence. The results showed that the two parrots with limited vocabulary immediately acted out the correct physical, insightful task. The parrots that had received training in referential English speech attempted instead to manipulate their trainer. They engaged in deliberate communication as a problem-solving strategy, which is an advanced stage of development, even for human infants. The most famous African Grey Parrot, Alex, exhibited cognitive capacities comparable to those of marine mammals, apes, and 4 to 6 year old children. Some of Alex’s accomplishments included the ability to label 50 different objects, 7 colors, 5 shapes and quantities up to and including six. He would combine these labels to identify, request, refuse, categorize, and quantify about 100 different objects. Alex also had functional use of phases and had a concept of category. African Grey Parrots have behavior patterns that match some non-human primates and that parallel combinatory development. In an experiment performed by Galef (2004), African grey parrots were observed to copy a variety of actions involving six different body parts and to associate each action with its appropriate label. This is a form of social-learning and imitation. (Galef, 2004; Pepperberg, 2001; Pepperberg, 2006; Pepperberg, 2007)

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. (Bottoni, et al., 2003; Luescher, 2006; Pepperberg, 2000)

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). (Athan and Deter, 2000; Faye, 2006)

  • Animal Foods
  • insects
  • Plant Foods
  • leaves
  • seeds, grains, and nuts
  • fruit
  • flowers

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. ("African Grey Parrots", 2006; Athan and Deter, 2000)

Ecosystem Roles

African grey parrots may disperse the seeds of fruits they eat. They act as definitive hosts to both tapeworms and blood parasites. ("African Grey Parrots", 2006; Athan and Deter, 2000)

Commensal/Parasitic Species
  • tapeworms (Cestoda)
  • blood parasites

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. ("Psittacus erithacus, Linnaeeus, 1758", 2008; Fahlman, 2002; Juste, 1995; Melo and O'Ryan, 2007)

Economic Importance for Humans: Negative

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

Conservation Status

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. ("CITES species database", 2008; "The IUCN Red List of Threatened Species", 2008)

Other Comments

In captivity, African grey parrots often suffer medical problems such as obesity, hypovitaminosis A, hypocalcemia, amino acid imbalance, or micromineral deficiencies. Problems are often associated with poor diets composed of seeds and nuts with supplemented fruits. These food sources contain high levels of carbohydrates. African grey parrots can also have calcium deficiencies which can lead to seizures. They can suffer from respiratory ailments caused by fungal diseases, bacterial infections/pneumonia, and nutritional deficiencies. Other health issues observed are; hyperkeratotic swellings, malignant tumors, tapeworm and blood parasites. They are also susceptible to Psittacine Beak and feather Disease (PBFD). ("African Grey Parrots", 2006; "Psittacus erithacus, Linnaeeus, 1758", 2008; Ryan, 2002)

In captivity, African grey parrots are prone to certain behavioral problems. For example, feather picking in response to social stress. Territory issues can also arise and are more common in males than females. (Athan and Deter, 2000; Faye, 2006)

Captive African grey parrots thrive on a diet of seeds, grain, pellets, and fruits and vegetables. It is suggested that pet owners supplement the diet with calcium in the form of dark leafy greens, calcium-rich vegetables, fruits, oatmeal, almonds, walnuts, hazelnuts, and sesame seeds. Flax seed and sunflower seed are also strongly recommended. Recent studies have suggested that pelleted diets are considered nutritionally superior to homemade diets and seed mixtures and may reduce the risk of abnormal grit consumption. (Athan and Deter, 2000; Faye, 2006)

Contributors

Tanya Dewey (editor), Animal Diversity Web.

Rachel Holman (author), Northern Michigan University, Alec R. Lindsay (editor, instructor), Northern Michigan University.

Glossary

Ethiopian

living in sub-Saharan Africa (south of 30 degrees north) and Madagascar.

World Map

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

altricial

young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.

arboreal

Referring to an animal that lives in trees; tree-climbing.

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

choruses

to jointly display, usually with sounds, at the same time as two or more other individuals of the same or different species

colonial

used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.

crepuscular

active at dawn and dusk

diurnal
  1. active during the day, 2. lasting for one day.
ecotourism

humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.

endothermic

animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

frugivore

an animal that mainly eats fruit

granivore

an animal that mainly eats seeds

herbivore

An animal that eats mainly plants or parts of plants.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

migratory

makes seasonal movements between breeding and wintering grounds

mimicry

imitates a communication signal or appearance of another kind of organism

monogamous

Having one mate at a time.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

omnivore

an animal that mainly eats all kinds of things, including plants and animals

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pet trade

the business of buying and selling animals for people to keep in their homes as pets.

riparian

Referring to something living or located adjacent to a waterbody (usually, but not always, a river or stream).

scrub forest

scrub forests develop in areas that experience dry seasons.

seasonal breeding

breeding is confined to a particular season

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

social

associates with others of its species; forms social groups.

suburban

living in residential areas on the outskirts of large cities or towns.

tactile

uses touch to communicate

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

tropical

the region of the earth that surrounds the equator, from 23.5 degrees north to 23.5 degrees south.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

2006. "African Grey Parrots" (On-line). Accessed April 10, 2008 at Eliteparrotsclub.com/articles/species/mediumsmall/africangreyparrots.html.

2008. "CITES species database" (On-line). CITES. Accessed April 14, 2008 at http://www.cites.org/eng/resources/species.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.

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.

2008. "The IUCN Red List of Threatened Species" (On-line). Accessed April 15, 2008 at http://www.iuncredlist.org/search/details.php/47991/clss.

Athan, M. 1999. Barron's Guide to Companion Parrot Behavior. New York, New York: Barron's Educational Series.

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.

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.

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.

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.

Galef, B. 2004. Social Learning and Imitation. Biology of Behavior, 4: 261-269.

Hallander, J. 2001. "Flock Behavior: How it Affects our Companion Parrots" (On-line). The Grey Play Roundtable, African Grey Info. Accessed April 10, 2008 at africangreys.com/behavior/flocks.htm.

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.

Luescher, A. 2006. Manual of Parrot Behavior. New York, New York: Blackwell Publishing.

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.

Pepperberg, I. 2000. The Alex Studies, Cognitive and Communicative Abilities of Grey Parrots.b. Boston, Massachusetts: Harvard University Press.

Pepperberg, I. 1991. A Communicative Approach to Animal Cognition: A Study of Conceptual Abilities of an African Grey Parrot. Pp. 153-186 in C Ristau, ed. Cognitive Ethology, the Minds of Other Animals, Essays in Honor of Donald R. Griffin. Mahwah, New Jersey: Lawrence Erlbaum Associates.

Pepperberg, I. 2007. When Training Engenders Failure to Imitate in Grey Parrots (Psittacus erithacus). Proceedings of the 4th International Symposium on Imitation in Animals and Artifacts: 0-10.

Pepperberg, I. 2006. cognitive and Communicative Abilities of Grey Parrots. Applied Animal Behavior Science, 100: 77-86.

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.

Ryan, T. 2002. Grit Impaction in Two Neonatal African Grey Parrots (Psittacus erithacus erithacus). Avian Medicine and Surgery, 16: 230-233.

Wright, M. 2002. "Understanding the Wild Nature of our Dreys" (On-line). Accessed April 10, 2008 at http://www.lafeber.com/Laferber-Library/Articles/wright/wildnature.asp.