Giant Panda (Ailuropoda melanoleuca) Fact Sheet: Behavior & Ecology

Active day and night

• General activity
  • Inactive for long period
    • May spend 41% of the day at rest, c. 9.8 hours
    • Most rest periods last 2-4 hours
  • Activity peaks at dawn and dusk (crepuscular)
    • Some activity occurs throughout all times of the day and night
    • Accounts for c. 59% of the daytime hours, c. 14.2 hours
    • Activity increases in June and November, though levels are also associated with variation in weather
• Do not hibernate
  • Unlike other bears
  • Constant access to food makes dormant period unnecessary
  • Bamboo is a poor nutrient source; pandas can't eat enough to gain fat deposits needed for hibernation
• Drink at least once/day
  • Consume water from puddles or streams
• Behavior supports energy conservation
  • Avoid travel up steep slopes
  • Communicate with scent rather than undertaking direct confrontation
  • Do not defend territorial boundaries
  • Remain within in small ranges

Daily activity pattern

• Activity in the wild, one study (Schaller et al. 1995)
  • Rest 41% of time
  • Feed 55% of time
  • Travel 2% of time
  • Other actions (scent-marking, grooming) 2% of time
• Activity in managed care (Mainka & Zhang 1994)
  • Sleep 40% of time
  • Rest 21% of time
  • Feed 25% of time
  • Walk 13% of time
  • Socialize 1% of time

Home range size

• Males with larger ranges than females (Schaller et al. 1985; Yong et al. 2004; Zhang et al. 2014)
• Extreme values 5-18 km² (as reported in Garshelis 2004; Zhange et al. 2014)
  • 4-6.5 km², one study, though authors recognize the value is likely an underestimate of the true range size (Schaller et al. 1985)
  • c. 11.5 km², estimate based on newer technology, high-resolution GPS telemetry (Zhang et al. 2014)

Use of range

• Inhabit only a fraction (10%) of range each month
• Usage seasonally variable
  • Descending slowly to lower elevations for winter, studies in Foping Nature Reserve, China; transition time lasting c. 36 days (Yong et al. 2004)
  • Returning to summer ranges more quickly; <1 month, though observations of as little as 2-3 days reported (Yong et al. 2004; Zhang et al. 2014)
  • Degree of seasonality may be dependent on population location (Yong et al. 2004)
  • Winter home range size larger than in summer, though individual variability is considerable (Yong et al. 2004; Zhang et al. 2014)

Range overlap

• Home ranges overlap, but direct encounter between pandas are rare (Wei et al. 2015)
• Male ranges overlap extensively (Schaller et al. 1985)
  • One large male appears to dominate the use of the territory
  • Frequent chemical marking at "scent-stations" and travel routes help individuals avoid each other
  • Combat between males generally rare; though commonly observed at certain times, when females are in estrous (Nie et al. 2012)
• Female range perimeters often overlap those of others, female and male (Schaller et al. 1985)
  • In practice, however, females stay in a core area that has no overlap with other females
    • Female/female competition may be driven by access to limited den sites (Schaller et al. 1985)
    • Surprisingly, GPS-collared female recently shown to move up to 50 km (31 mi) out of her home range during mating season (Swaisgood et al. 2009)

Fidelity to core habitat

• Returning to same foraging areas suggests a well-developed spatial memory (Swaisgood et al. 2016)

Solitary most often

• Female remains alone, unless caring for young
• Breeding interactions brief and infrequent
  • Interactions last only a few days
  • Strong competition may occur between males in a breeding season

Polygynous mating system

• A single males will mate with multiple females (Schaller et al. 2002)

Adapt reproductive behavior to soliary context

• Exhibit considerable flexibility communication cues (e.g., signaling reproductive status) (Owen et al. 2016b)

Displays/visual signals

• Striking coloration may send signal to other members of the species
• Direct confrontation involves body posture and vocalization
  • Lowered head stare and head-bobbing may be accompanied by growl and/or roar
  • Ears do not move as in other species
• Aggression
  • Swatting with forepaws
  • Lunging
  • Grappling
  • Biting
• Lack of aggression
  • Turning head
  • Dropping head
  • Covering eyes and muzzle with paws

Vocalization

• Vocalization is infrequent
  • Associated with courting, social interactions
  • Not similar to the roars and growls of other bears, in general (Loeffler et al. 2006)
    • Black ear and giant panda both moan to indicate slight aggression
    • A high-pitched chirp (yip) may be unique for giant pandas (Schaller et al. 1985)
• Females utter distinctive chirps that advertise their fertile phase (Charlton et al 2009)
  • In an experimental setting, males are much more attracted by fertile phase chrips
• Male pandas bleats provide information about their testosterone levels (Charlton et al 2010)
  • Male vocalizations were recorded and matched with the caller's hormone profile
  • Higher testosterone levels correlated with longer lasting bleats and changes in sound quality
  • Females can use this information to choose between males
  • Males can use these cues to avoid potentially dangerous rivals
• 11 distinctive vocal and unvoiced (jaw-pop) sounds identified (Kleiman & Peters 1990)
  • Bleat is social/friendly; conveys information about caller identity (studies by Charlton et al.)
  • Huff, snort, chomp indicate apprehension
  • Honk, squeal indicate distress
  • Growl, roar indicates aggression
  • Moan, bark, yip, chirp may be emitted in varying combinations and with varying intensities
• Giant pandas are the only bears that do not hum (Peters et al. 2007)

Olfactory signals

• Sophisticated sense of smell (White et al. 2003) (Swaisgood et al. 2002) (Swaisgood et al. 2004)
  • Can detect sex, age, reproductive condition of scent maker
  • Able to distinguish identity of individuals
  • Can tell kin (related individuals) from nonkin using urine and body odor (Swaisgood et al. 2016)
    • Females interested in scents of unrelated females
  • May differentiate time since deposition of scent mark
• Leave both anogenital gland and urination scent marks (from White et al. 2003)
  • Deposit scent on surfaces of trees and rocks
• Mark environment at communal scent stations and along established travel routes
  • Bark stripping (by biting or clawing)
  • Ground pawing
  • Rubbing and rolling
  • Tree scenting with secretions from anogenital glands
  • Urination
• Chemical communication in pandas in managed care reveal (Swaisgood et al. 2000) (White et al. 2002):
  • Four marking postures by pandas possible, at various heights:
    • Squat (deposits scent on ground) - most commonly used by females
    • Reverse (leaves scent by backing up to vertical surface) - most commonly used by adults
    • Legcock (leaves scent with one leg raised against vertical surface) - used more often by males
    • Handstand (scent and urine marks left high on vertical surface) - used by adult males (Swaisgood et al. 2000)
  • Individuals respond depending on height of odor mark
    • Highest marks caused more investigative behavior
    • High marks may indicate male's competitive abilities and aggressive intent
  • Females also convey competitive status by making high-placed scent marks
    • Females don't compete with each other over males or food resources, but perhaps over rare denning sites

Participants

• Primarily an activity of young

Forms of play

• Tumble and roll
• Partial and complete somersaults
• Lateral rolls
• Body twisting
• Slide down snowy slopes

Gait similar to other bears

• Extremely agile
  
• Stride of pandas is typically longer
• Walk with a rolling gait
  
• Described as "ambling", "pigeon-toed", or "waddling"
• Head held low
• Limbs on the same side move forward and backward at the same time
• Rarely gallop
• Rapid movement through thick bamboo is difficult
• Climb into trees
• Move into trees to sun, rest, and escape danger
• Individuals may move into trees to avoid sexual advances
• Young climb more easily than adults
• Offspring often remain in a tree while mother forages (Lü et al. 1994)

Travel

• Speed of travel
  
• Move c. 2-3 km/hr
• Cover short distances each day, typically
• May travel less than 1 km/day
• Most movement related to foraging

Competitors

• Mammalian "stem and leaf" eaters
• Golden monkeys, takin, red pandas, Asiatic black bears, and many pheasants live in the same geographic areas as giant pandas
• Red panda and bamboo rats also consume bamboo
• Monkeys consume leaves
• Ungulates unlikely to greatly impact panda numbers as they are few in number
• Sambar deer, serow, and tufted deer live in the same geographic areas as giant pandas
• Presence of some may impact the number of pandas an area can support

Predators

• Juveniles and young most susceptible
• Yellow-throated marten, weasel, golden cats, dholes prey on juvenile giant pandas

Pandas are adept tree climbers when seeking a bit of sun, some peace and quiet, or safe refuge.

Image credit: © San Diego Zoo Wildlife Alliance. All rights reserved.

Catton (1990)
Charlton et al. (2009)
Charlton et al. (2010)
Garshelis (2004)
Hagey & MacDonald (2003)
Kleiman & Peters (1990)
Lü et al. (2008)
Mainka & Zhang (1994)
Nie et al. (2012)
Schaller et al. (1985)
Swaisgood et al. (2000)
White et al. (2002, 2003)
Zhang et al. (2014)