Athan and Deter, ; Melo and O'Ryan, Psittacus e. 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. 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, ; Melo and O'Ryan, 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.
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.
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. 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 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.
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 , 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. He would combine these labels to identify, request, refuse, categorize, and quantify about 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 , 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, ; Pepperberg, ; Pepperberg, ; Pepperberg, 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. Two 2'' x 4'' perches inserted in construction brackets, affixed with stainless steel nuts and bolts, make changing perches an easy task. Essentially half of the cage is protected from the elements.
One end includes a perch to the nestbox, nestbox, and feeding station. The back half of the cage with one perch is open to Mother Nature. The same basement nestboxes are being used. Two of the more restless pairs of African Greys were offered two nestboxes. Many of our greys are nervous and immediately head into the nestbox when anyone enters the bird yard. We rarely get to see them unless we peek out of the house through a window.
These birds still produce regularly. Neighboring birds are a mixed variety of psittacines, some of which are directly opposite the row of grey parrots.
Although the individual pairs cannot see one another, they do communicate by whistling. Whistling is intensified at night during breeding. Approximately two weeks after the chorus begins, we know to check our nestboxes. It has been unusual to have only one pair of birds on eggs or chicks at a time. In Florida, our African Greys' nesting season generally begins in December and continues through June. During this period, we will get up to two clutches per pair.
It appears that our hens do the incubating while the males provide the hens with food in the nestbox. We do know that we have one hen that does leave her eggs or chicks to receive her daily share of approximately ten sunflower seeds. We no longer use rabbit feeders for containing the pellets.
The humidity and frequent summer rains prevent this convenience from being efficient. Each pair of birds is offered one half cup of Lafeber's Special Needs pellets with approximately one level tablespoon of sunflower seed-based parrot mix sprinkled on the top. No other supplements are provided. Egg laying will use up a great deal of calcium.
African Grey parrots usually become sexually mature by 7 years old. They usually lay eggs per year. You cannot rely on tail feathers to determine sex unless your grey is 18 months of age or older. African Grey Parrots reach sexual maturity by four years of age. We have had third generation Timnehs produce fertile eggs at three years. Commercial breeding operations primarily occur in South Africa, where more Greys are reared than in the whole US combined. If your Parrot lays an egg, leave it alone for a few days.
Watch your bird to see if she shows any interest in the egg. She may ignore it as first. Parrots often take a few days to lay a full clutch of eggs.
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