By Greg Glendell. Adapted from an article originally published in Parrots magazine 2009.
All birds have a large range of behaviours, which are essentially innate; they are born with the ability to carry out these behaviours; though there will be variation in how each individual bird carries out each behaviour. In grey parrots there are a range of calls, postures and actions which the birds use to communicate detailed information to each other. This relates to the bird’s fears, likes, dislikes and methods of avoiding harm (predator avoidance). Many of the behaviours are carried out by very subtle combinations of raising or lowering certain feathers, particularly the feathers on the head, back and neck. The process of determining accurately the purpose of each behaviour is not easy to achieve. First, you need a group of birds of the same species which you can observe as they interact with each other. It is important that the birds cannot see you while you are recoding their behaviours, as you should not influence their behaviour. Next, each behaviour is described in some detail and given a name. Finally, you need to carry out some tests so as to determine accurately what the purpose of each behaviour is. You should then be able to predict interactions between the birds and between birds and people. This is what I have done this for this species. The result is the decoded ‘language’ for the species studied, called an ethogram. It cannot be transferred to other species. Each species has their own complete set of signals which is different from other species of parrots, though some behaviours may be similar to closely related species.
The 34 signal/behaviours have all been seen in Timneh grey parrots and most (but not all) have been seen in African greys. In most cases the birds were not aware of being watched by people while they gave the signals. The observations come from birds observed over 16 years in bird parks, cages and aviaries of bird-keepers, birds at liberty and in caged birds offered for sale. In most cases an attempt has been made to interpret the function of each behaviour. Most behaviours can be classified as either affiliative (Af) (friendly, social behaviour) or agonistic (Ag) (anti-social, aggressive, or assertive). Some behaviours are termination behaviours, performed as a way of signalling the end of another activity. A few are ‘commencement’ behaviours; these are performed where the bird is preparing itself to carry out some other task. Some behaviours are neutral (N) or I have not been able to determine their function. Some of these interpretations are only provisional. The signals are listed in alphabetical order of given name. I have not been able to observe many behaviours which may occur while birds are in sustained flight. All of the behaviours below are innate behaviours; every grey parrot is born with the ability to do these behaviours, and, given the stimulus, will carry them out as appropriate. They are not ‘learnt’ behaviours or ‘tricks’. They are part of this species’ behavioural repertoire and they form a valuable key into understanding your bird’s likes and dislikes, fears and degree of contentment. It is vital to back away immediately from any bird if it ever shows fearful behaviours such as growling.
1.Aighr! Aighr! Bird makes loud, repeated, medium pitched “Aighr, aighr” noise while (usually) flying in an excited, erratic or eccentric manner.
Interpretation: Af. invitation to play?
2. Attack. Most body and head feathers raised as in Mantling (No. 17). Bird walks or runs towards source of stimulus with head lowered and bill half open, may blaze eyes (see No. 6). ‘Opponent’ may adopt a similar stance, or fly away. Where opposed, both birds may fight bite attempting to bite eachothers eyes or beak, as their eyes blaze wildly (No 6).
Interp: Ag; behaviour regarding space, food, or threat to one’s mate.
3. Chuck, chuck. Bird makes a soft “chuck, chuck” sound on alighting a perch after having been flying. Call not repeated more than twice.
Interp: Af; Short distance contact call? Termination signal?
4. Clicking. Bird makes clicking sound, 1 to 4 times, by snapping the lower mandible against a notch in the upper mandible. All feathers usually held down though may raise feathers on back (but never on rump) very briefly.
Interp: Ag. Warning/assertiveness/irritation. Bird does not wish to be disturbed, or interact with another. May blaze eyes (see No. 6) if further provoked.
5. Drawing. Bird touches any surface it may be stood on, and with its beak ‘draws’, making erratic or semi-circular movements, pausing to raise its head occasionally (not seen in Af grey).
Interp: Af/Ag? Assertiveness/confidence, desire to initiate some action, impatience, desire for play?
6. Eye blaze. Pupils contract rapidly but briefly while head (usually but not always) held forwards and lowered. Contraction/dilation may be repeated 2 or 3 times. Sometimes, some head and neck feathers are raised, and bird may “Click” (No. 4).
Interp: Ag + Af; Bird is excited (negatively or positively). This signal should not be confused with the bird’s focussing at close distance. In close-focussing, the bird contracts its pupil (iris) to increase depth of field to be able to focus at near-beak distances; e.g. while feeding.
7. Flapping. Stance similar to v-wings (No. 30 below). While perched, bird flaps wings 3-5 times in stereotypical manner while perched with an upright stance; head held forwards. Feathers on back may be raised.
Interp: Af to mate. Ag to others? Territorial? Advertisement of presence to birds known by the signaller (peers and/or mate).
8. Flight Attack. All body feathers held down tightly; bird is always standing on both feet and looks very alert with staring eyes. Bird flies at opponent with no discernible warning (either audibly or visually) usually trying to gain height over the opponent and striking with feet and/or beak while in flight.
Interp: Ag. Intention to drive another bird away.
9. Fluffed up. Bird has upright stance and may rest on one foot only. Most body feathers (but never any wing feathers) are slightly raised, but relaxed. Feathers around chin/cheeks, forehead and back of head (but not neck) clearly raised but feathers on middle of top of head are flattened.
Interp: Af/N. Bird is relaxed, sleepy; may not wish to interact with other birds/people.
10. Growl (fear). Bird makes loud, throaty continuous growling sound. Body feathers held down tightly.
Interp: Ag; Bird is fearful, not aggressive.
11. Growl (threat). As fear growl, but most body feathers including wing coverts are raised. Bird may Click (No. 4) as well.
Interp. Ag; fearful, but not as fearful as in No. 10. Bird wishes to remain where it is while repelling an intruder.
12. Hackles. All feathers on back of neck and upper back raised and lowered very briefly.
Interp: Ag/N; Mild aggression or determination/mild frustration or ’commencement activity’ while bird prepares to do something which requires extra attention, such as fly to an unfamiliar perch, or approach a new object. Shows bird is concentrating/determined?
13. Head pumping. Head is moved up and down vertically and rhythmically 2-6 times while body is motionless.
Interp: Af to mate; Ag. To others? Conspicuous show of assertiveness, confidence, territorial display?
14. Hollow whistle. Bird leans forward and downwards while making single hollow-sounding whistle.
Interp: Af to mate; Ag to others: Bird is alert, confident, but not alarmed. Mild threat/provocation to other greys except mate?
15. Kissing (in mated/bonded pairs only). Birds gently lock beaks briefly, one bird’s beak at 90 degrees to the other; heads sometimes dipped together several times. May proceed to mutual feeding (see 18).
Interp: Af; Greeting between a bonded pair.
16. Knocking. Bird uses front of bill to tap 2 to 6 times on any surface that may produce a resonant sound, e.g. nestbox, windowpane.
Interp: Af to mate; Ag to others. Territorial display?
17. Mantling. Feathers on back, dorsal side of neck and back of head are raised; may also raise feathers on upper wing-coverts. Eyes appears wide and staring, never sunken in. May blaze eyes; may spread/fan tail (rare).
Interp: Ag; Threat/warning of intention to attack the source of the stimulus by walking (not flying). May follow this by Attack (No. 2).
18. Mutual feeding. As kissing, but one bird (usually the male?) passes regurgitated food to the female. Female further stimulates male by pumping her head rhythmically up and down during food exchange, and ‘kissing’ the male.
Interp: Af. Courtship, foreplay, maintains pair bond?
19. Mutual preening. One bird preens the other. Invariably this is confined to the head or upper neck area only. Both birds are usually relaxed with eyes sunken in; most head feathers are raised but ‘relaxed’ on the receiving bird. Body feathers may also be slightly raised on receiving bird.
Interp: Af. Maintains pair bond/courtship in paired birds? Af in non-bonded birds/siblings/peers?
20. Ostrich/fear huddle. (Only seen so far in caged birds while in the company of humans). Bird attempts to hide by facing away from source of stimulus, hiding its head in corner of cage on the floor. Bird remains stationary. May growl if disturbed. Often seen in a group of birds who all congregate in a ‘fear huddle’ in the same corner of the cage.
Interp: Ag. Extreme fear response in highly stressed birds.
21. Rasping. Lower bill rubbed/vibrated repeatedly by being drawn inwards against inside of upper bill, producing a rasping or purring sound. Bird is stationary, relaxed and may stand on one foot only. Often done at or before roosting or during afternoon ‘siesta’. The only sound likely to be heard during darkness. Body and appearance as in ‘Fluffed up’.
Interp: Af. Close contact/ reassurance call? Self-comforting behaviour? Other bird(s) reply by rasping as well.
22. Scratching. Bird scratches the floor, first with one foot, then the other in a rhythmic, rather stereotypical manner. The head is held low, never above the height of the bird’s back, the beak usually touching the floor, or holding on to the cage wire. Not often seen in adults but usually in immature birds.
Interp: Ag; Frustration at confinement? Substitute nest-excavation behaviour?
23. Scratch Request. Head held low and brought forward (bill may be touching perch) while head and some upper neck feathers are raised. ’Chin’ feathers always raised. Eyes may be partially closed or appear sunken in. Bird stands quite still.
Interp: Af; Invitation for mutual preening/head scratch. Pro-social/friendly (submissive when displayed to an aggressor?)
24. Screech. Bird makes screeching/screaming sound, usually once only. May blaze eyes.
Interp: N/Ag; Excitement mixed with irritation or frustration (at self/object or other bird?).
25. Squawk. Single loud, harsh note, repeated 2-6 times, sometimes more. All feathers held down tightly. Often given on sight of a cat or dog, or unfamiliar/close approach of unfamiliar person or object. Bird may fly immediately in panic.
Interp: Ag. Contact call when produced at low volume and not repeated. But fear/alarm call when volume increased and call repeated. Invitation to take flight? Predator escape response? Or sight of some other threat to self, mate or peers?
26. Strutting. Bird walks in exaggerated, pompous manner; swaggers and stomps each foot down as it walks with the head held upright. Not seen on Af. grey.
Interp: Af to mate; Ag to others? Assertiveness/territorial display?
27. Swaying. Bird’s feet remains in fixed position while swinging its head and sometimes whole body conspicuously in an eccentric manner several times. Often this behaviour is a prelude to, and associated with Strutting. Not seen in Af. Grey.
Interp: Af to mate; Ag to others. Assertiveness, intimidation, or invitation to play?
28. Tailshake. Tail shaken rapidly but only briefly from side to side, sometimes accompanied by shaking of body feathers.
Interp: Af/N; Bird is relaxed and ready or keen to do something. Commencement activity. And/or termination activity seen after bird has carried out some other familiar activity. Also sometimes seen after ‘kissing’ when bonded birds greet each other.
29. Turn away. Bird turns sideways to another (opponent?) lowers head and usually walks briskly away. May use a side-step/skipping action, keeping head down and eyes out of sight of opponent. May raise ‘chin’ feathers.
Interp: Af/N; Appeasement/submissiveness. Bird wishes to avoid conflict?
30. V wings. Head is drawn in to shoulders, wings raised up over back by extension of humerus/shoulder joint, and primaries flicked out and in 2 to 4 times by extending and flexing at wrist. Usually performed when the bird sees another familiar bird (or human) after a short absence.
Interp: Af. ‘Greeting’ given to birds (or humans) known to the bird?
31. Wing-drop/chuckle. Wings held down and out from body; body feathers held down tightly, beak partly open, tongue may be seen moving. Bird may make chuckling sound. Mating may follow in bonded pair.
Interp: Af; Courtship; bird is sexually aroused.
32. Wing flip. Bird flips one wing out and then back in by sudden extension at shoulder joint only, producing a single, soft flicking or clapping sound. May repeat this with other wing or same wing within a few seconds of first flip. Bird never flips both wings at the same instant. Body feathers held flat down but not always tightly. This identical behaviour is seen in a range of other parrot species.
Interp: N/Ag. Termination activity and/or bird does not wish to be disturbed? Bird may object to being disturbed by another, which it may then threaten, following a wing-flip. Self-comforting behaviour?
33. Wing-stretch. Both wings raised together once only, by extension from shoulder joint only (primaries not extended). May be followed by synchronous stretching of left or right limbs.
Interp: Af; Greeting offered to known bird (or human)? Commencement activity?
34. Yow! Bird makes sudden, irritated “Yow!” sound and adopts an upright stance. All feathers held down. Not seen in Af grey.
Interp: Ag; Bird objects (and rejects) something that has happened to it. Occurs during minor squabbles or rough play with another bird.
