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Species: Gorilla

Use: General Activity

Authors: T. duBois, J. Mead, C. Cox, L A Zoo.

Methods: N/A

Publications/Presentations: N/A

Masturbation

Manual: An animal rubs its genitals repeatedly with hands.

Pelvic rub: A female back up to an object (tree, rock, etc.) and rubs anogenital area against it.

Haunch-bounce: While in a squatting position, a female bounces up and down on her haunches. (Referred to as EvieÕs ÒhiccuppingÓ).

Coo vocalization: Pursed lip vocalization sometimes given when females masturbate.

Anogenital touch: An animal examines or fondles the anogenital region of another.

Anogenital sniff: An animal sniffs the anogenital region of another, excluding occasions when the latter animal has just defecated or has feces on fur.

Stare: A female stands motionless while intensely observing the male.

Head jerk: While staring, a female intermittently jerks head to the side. The body is relaxed and lips are not compressed. (Referred to as Òthe come hither lookÓ).

Extended arm invitation: A female extends her arm with open palm toward the male.

Ground or object tap: While orienting toward the male, a female repeatedly taps ground, rock or log with both hands (as if playing a drum).

Haunch-scoot: While squatting, a female uses her arms to propel herself on her haunches toward the male.

Quadrupedal bounce: While standing on all fours and facing another animal, a female bounces hindquarters up and down. (Similar to haunch-bounce but done while animal is standing Ð may be form of masturbation as well as sexual solicitation).

Pronk: While standing on all fours and facing another animal, a female hops about in a jerky fashion. The hindquarters are slightly elevated. (Behavior ÒinventedÓ by Cleo).

Pronk-mount: A female pronks while grasping another animal around the waist.

Present: A female stands quadrupedally and orients anogenital region directly towards another animal; hindquarters are slightly elevated (but not an exaggerated display as in some primates).

Back into: While presenting, a female walks backward directly into another animal.

Play present: A female presents in a playful context. Form is generally exaggerated, e.g., animal bends way over the head close to the ground and rump in the air. (May occur only in young animals).

Spread-legs display: A female slides on an incline past another with legs spread widely apart. Occurs in a playful context.ÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊÊ

Crouch: A female bends low to the ground with her limbs pulled in. Another animal may then mount dorso-ventrally.

Lie prone: An animal lies flat on the ground face downward during a sexual encounter.

Lie supine: An animal lies flat on the ground face upward during a sexual encounter.

Dorso-ventral mount: An animal mounts another from behind.

Ventro-ventral mount: An animal mounts another from the front. (Both animals face each other).

Ventro-ventral mount of infant: An adult animal stands quadrupedally over a supine infant and thrusts without making contact.

Awkward mount: An animal mounts another, but orientation is improper, e.g., mounts from side, etc.

Mount and thrust: An animal mounts another and thrusts, but intromission does not occur.

Copulation: An animal mounts another and intromission occurs (hard to determine whether ejaculation occurs).

Coo vocalization: Pursed lips vocalization given by female which may occur before, during or after copulation.

Reach and touch: During copulation, a female reaches around with one arm and touches male on the head.

Social play: Repetitive, exaggerated, disjointed, and seemingly non-purposeful behavior involving two or more animals. May have both gentle and aggressive components. The list is almost infinite but includes the following:

Climb or stand on another, turn circles around another, piggy back ride, peek-a-boo, mouth, tickle, foot dangle (an animal dangles foot in front of another), tap on another, dangle (an animal an infant by its hands and allows it to dangle in the air), arm shake, run-away (one animal runs away from another as an invitation to chase), chase or play tag, swagger walk, chest beat, beat or slap other body part, ground or water slap, object wave, shake, or brush on ground (usually a branch), object throw/hit, object tug/grab, swat, push or nudge, grab/pull, kick, wrestle, bite, play-face (relaxed open mouth expression with teeth exposed).

Approach: An animal draws closer to another: because of context and relaxed body posture, motivation presumed to be friendly.

Follow: An animal walks behind another; because of context and relaxed body posture, motivation presumed to be friendly.

Muzzle-muzzle: An animal places its face directly in front of another (within 6 inches).

Groom/inspect: Using the hands or mouth, an animal grooms or examines anotherÕs body parts, excluding the anogenital region when feces being removed.

Active contact: Friendly contact behaviors which occur outside of play context. Includes the following:

Touch (excluding the genitals), grasp, sniff (an animal sniffs anotherÕs body parts, excluding anogenital region unless feces are obviously being sniffed), mouth, kiss (an animal puckers its lips against head or face of another), pat or caress, hug or embrace, hold, huddle (animals sit in groups of two or more with bodies in close contact).

Passive contact: An animal sits, lies, or sometimes walks with body in contact with another. Behavior is not as Ò intimateÓ as active contact, e.g., animal may sit with only feet touching.

Inside with: Two or more animals, excluding infants being carried, are inside cave or planter together and are not visible to the observer; assume association to be affiliative, although specific behaviors not visible.

Food offer: An animal offers food, browse, or regurgitate to another.

Rock: A mother supports her infant in arms or on lap and rocks it back and forth.

Jiggle-bounce: A mother supports her infant in lap or on legs and bounces and jiggles the infant.

Dangle-groom: A mother dangles her infant by one ankle and grooms the anal area.

Flex-manipulate: An animal bends and manipulates the infantÕs body parts.

Coax: A mother places her infant on the ground and then walks away and stands or sits at a distance. The mother observes the infant intensely, seemingly encouraging it to approach.

Retrieve: An animal picks up an infant when infant is alone.

Restrain: An animal holds an infant firmly when the infant attempts to leave.

Shield: An animal uses its arms or body to shield an infant from another animal or potential danger.

Climb on or over: An infant climbs on or over another animal.

Nose/eye poke: An infant pokes its finger in anotherÕs nose or eye.

Manipulate motherÕs nipples: An infant pulls at or handles motherÕs nipples (not to be confused with rooting behavior).

Distress vocalization: An infant whines or cries when alone; appears to be an attempt to get mother to return.

Agonistic: An animal turns away from another in order to avoid, but does not vacate its spot.

Avoid: An animal moves away from or gets out of path of another.

Crouch: An animal crouches when threatened or attacked by another.

Hide: An animal presses itself against a surface so that it is hidden or partially hidden from the view of another.

Supplant: One animal approached another and the latter moves away. The approaching animal then takes that spot.

Stare: A fixed, unwavering stare at another with brow furrowed and facial muscles tense.

Tight-lip face: A facial expression in which the lips are tightly compressed and the head diverges from side to side.

Stiff stance: An animal stands with the legs held rigidly and the body stiff and erect; tight lip face often accompanies.

Strut-walk: While in the stiff stance, an animal walks with stiff, short steps.

Directed chest beat: An animal chest beats while orienting toward another gorilla in the same exhibit.

Directed object slap: An animal orients toward another and slaps ground, rock, wall, inside door, or makes loud splash in the pool.

Bluff charge: An animal runs on the diagonal past another but does not make contact.

Rush charge: An animal rushes up to and stops just short of another.

Charge with chest beat: While charging, an animal beats its chest.

Charge w/object display: While charging, an animal waves or throws an object or slaps ground with an object (usually browse).

Charge and hit: While charging, an animal hits another with an object (usually browse).

Leg kick: An animal kicks its leg in the air at the end of a charge, chest beat or object display.

Object grab: An animal snatches an object or browse away from another.

Object drop or throw: An animal drops an object down on another from above, or throws an object at another.

Hit with object: An animal hits another with an object.

Hit/slap: With hands.

Push

Grab/pull

Chase

Open-mouth threat: A tense, open-mouth expression with lips raised and pulled back so that canines are exposed; muscles and the forehead are taut and drawn back.

Soft pant-hoot: A quiet vocalization in which an animal makes rapid exhalations through ÒoÓ shaped lips. The abdomen may be seen heaving up and down.

Scream

Pig grunts: Short, rough, guttural grunts.

Growl: A deep, guttural noise similar to a dogÕs growl.

Bark: A deep, gruff noise similar to a dogÕs bark.

Roar: A loud explosive outburst given by a male silverback.

Herd/herded

Herd: A silverback male controls the movement of a group by following at a close distance (formally called pursue; may be an attempt to keep females together and in sight).

Herded: Refers to a group being herded by a silverback male. Animals appear to be avoiding the male as they move away whenever he approaches.

Observe: An animal watches another gorilla in the same exhibit.

(The following behaviors are directed to gorillas in

1. An adjacent exhibit,

2. In night quarters, or to

3. ÒmissingÓ gorillas (gorillas which have recently been sent out).

Observe: An animal watches another gorilla in an adjacent exhibit.

Display: Includes behaviors such as chest beating, object throwing, waving, etc., which are directed toward gorillas in an adjacent exhibit.

Bang door: An animal bangs on the inside door when there are group members kept inside night quarters.

Search: An animal travels about exhibit or goes in and out of cave seemingly looking for a missing group member.

Hoot series vocalization: Low pitched Òhoo hoo hoosÓ which can build up to more plaintive sounding, higher-pitched ÒhoosÓ. Vocalization often terminated by banging on door and has been heard only when group members are missing.

Head toss: An animal repeatedly tosses its head in circular fashion; sometimes followed by regurgitation and reingestion.

Arm fling: While sitting, an animal repeatedly flings its arm out for no obvious reason.

Hair pluck: An animal plucks hair from its own body, usually the facial region.

Self-flagellation: While sitting, an animal flogs itself with browse.

Regurgitation and reingestion: [Refers to behaviors in which food is brought up from the stomach to the mouth and then eaten. Gorillas tend to use idiosyncratic methods].

Reg. Into cupped hand: An animal regurgitates into hand and then eats out of hand.

Reg. Onto substrate: An animal bends over, regurgitates onto ground and then ingests directly from ground.

Bent-arm regurgitate: An animal lifts and bends arm at elbow while regurgitating in a jerky fashion into cupped hand.

Suck-regurgitate: An animal brings lips into extreme sucking position and brings regurgitate up into mouth.

Backward neck stretch regurgitate: An animal leans head backward with neck stretched taut, then regurgitates with mouth closed.

Regurgitate into mouth: An animal makes ÒoÓ shape with lips and brings regurgitate up into mouth.

Head jerk regurgitate: An animal jerks head in circular fashion while bringing up regurgitate.

Bend over regurgitate: While sitting, an animal bends over with mouth close to the ground and regurgitates into mouth.

Self-play and object explore

Self-play: Includes all solitary play behaviors which are not directed to other animals or to the zoo patrons, including:

Rock body, roll on ground or grass, somersault, turn circles, thigh slap/pat, chest pat (very mild chest beating), lip flap (using fingers), clap hands, manipulate body parts (exaggerated body or head rubbing, pulling on toes, etc.), water play (wading, splashing, etc.), object play (waving branches, tossing leaves in the air, playing with tubs, burlaps sacks, etc.).

Object explore and manipulate: Refers to all behaviors in which an animal uses its hands to investigate or handle objects, excluding those which are preparatory to feeding, including:

Browse manipulate, browse or object wear (an animal drapes browse, burlap sack, etc., over back, shoulders, head), other vegetation inspect/manipulate (rubbing grass on body, throwing grass clumps in air, etc.), manipulate feces or regurgitate (not associated with ingestion), poke at dirt/dig holes, rub self with dirt, mouth objects (including biting, sucking, licking, chewing, or manipulating with tongue), manipulate miscellaneous objects (such as drain covers), items thrown by patrons etc., observe objects (visual examination of an object which is being held or which is within reach), sniff objects, and carry objects (in mouth, hand, or small of back).

Food getting and ingestion

Ingest: Includes the following: eat browse, eat grass, weeds, leaves, bark, flowers, or other vegetation, eat miscellaneous food items (including food thrown in by keepers and patrons), spit food out, drink, eat food out of another animalÕs mouth (seen in infants).

Forage: Behaviors which are preparatory to feeding. Includes the following: gathering, carrying, or dragging browse, bark stripping, gathering and eating seeds, picking and/or carrying grass, weeds, leaves, bark, flowers, or other vegetation or food items.

Audience interaction

Audience interaction: Includes all behaviors in which an animal interacts with humans (keepers, patrons, etc.), or vehicles drawn in front of an exhibit. Includes: approach/observe, extend arm (animal stretches arm outward toward audience, probably begging for food), point at, clap hands, arm shake, blow kisses, self-play behaviors (which are obviously directed to audience), chest pats, splash water, object throw (including feces, dirt clods, rocks, etc.), threaten audience (animal directs agonistic behavior toward humans, including growl, roar, open-mouth threat, bluff charge, chest beat).

Carry/cling or ride

Ventral carry/cling: While standing or moving quadrupedally an animal carries an infant who clings to the ventrum.

Dorsal or lateral carry/cling: While standing or moving quadrupedally an animal carries an infant on the back, side, neck, shoulders or head.

Leg drag: An infant grasps anotherÕs ankle and clings while the latter animal walks about.

Extended arm carry: An animal carries an infant in palm of outstretched hand and walks tripedally (the Òfootball carryÓ).

Tripedal walk: An animal holds infant against the ventrum and walks tripedally.

Locomotion: [Includes all forms of movement and travel occurring outside of a friendly/social or agonistic context. Also excludes self play and occasions when an animal is carrying an infant.]

Walk quadrupedally: An animal walks on four legs.

Walk tripedally: An animal walks on three legs.

Walk bipedally: An animal walks on two legs.

Stand quadrupedally

Stand bipedally

Climb

Scoot

Slide

Roll

Jump

Hang by arms

Swing by arms

Run: (In agonistic context).

Change stance: Go from sitting to standing position, etc.

Special Locomotor behaviors observed in infants

Arm/leg flail: An infant jerks its arms and/or legs about in a seemingly random fashion.

Root: An infant gropes and moves head about motherÕs ventrum in search of motherÕs nipple.

Crawl: An infant drags its prone body along the ground.

Toddle: An infant walks quadrupedally with short, uncertain steps.

Rest and body maintenance

Rest: Periods of quiet repose in which any of the following behaviors may occur: Sit/lie without performing other behaviors, sleep, yawn, stretch, cough, comfort movements (slight position shifts or rolling over while resting).

Self-exploration and body maintenance: Includes the following behaviors: Groom/self-inspect (an animal picks at or examines its toes, hands, or any other body parts), oral explore (an animal mouths or licks its body parts), scratch, nose-pick, sniff self, rub eyes, pick teeth, rub self, poke anus/remove feces.

Urinate/defecate

Vomit: (When not part of R/R).

Look out/ look about: An animal sits or lies quietly but appears to be observing environment, although specific object of focus is not apparent (same as Òstationary alertÓ).

Special rest behaviors seen in infants

Nurse: An infant suckles at its motherÕs breast (it is often hard for an observer to tell whether an infant is nursing or sleeping, se we are including ÒnurseÓ under rest behaviors).

Other: [These include behaviors which do not readily fall into any category or whose functions are unclear].

Non-directed agonistic: Includes agonistic behaviors such as chest beat, growl, object slap, etc., which do not appear directed toward other gorillas or to audience, and which occur outside of play context.

Interspecific agonism: An animal directs agonistic behavior toward animals other than gorillas or humans (e.g. swiping at insects, chasing peacocks, etc.).

Visual explore environment: Includes the following: visual attention toward objects in environment which are not within reach (such as planes, helicopters, etc.), and observe animals other than gorillas or humans (such as peacocks, insects, etc.).

Eat feces

Drink urine

Eat anotherÕs regurgitate

Monitor/search: An animal looks about exhibit as if to locate the whereabouts of other group members.

Armpit sniff/touch/manipulate: An animal sniffs or touches own armpit, or manipulates area under armpit.

Nipple rub: An animal repeatedly rubs its own nipple.

Self-directed lactating behaviors: Behaviors shown by lactating mothers including: Manipulate nipples, squirt milk from nipples, and bend over to drink milk from own nipples.

Escape/escape attempt: An animal attempts or succeeds in climbing out of exhibit. May stand on back of another gorilla to reach handhold.

Nest-build: An animal manipulates browse around itself to form a crude, circular nest.

Not visible: An animal is not visible to the observer excluding cases of inside with.