Giant Panda (Ailuropoda melanoleuca) Fact Sheet: Diet & Feeding

Bamboo

• Eat bamboo, almost exclusively (Garshelis 2009b)
• Over 99% of diet is bamboo (Schaller et al. 1985; Hu and Wei 2004; Garshelis 2009b)
• Early studies from managed care settings; diet in the wild may be more flexible (Long et al. 2004)
• Diets of other bear species also high in plants, except for polar bears
• Pandas primarily eat about 35 bamboo species (Garshelis 2009b)
• But more than 60 bamboo species known from across their full geographic range (6 mountain ranges) (Chu and Long 1983, cited by Schaller et al. 1985; Garshelis 2009b)
• See Hu and Wei (2004) for which bamboo species consumed in different mountain ranges
• Amount of food eaten
• For an average-sized panda (weighing 100 kg, or about 220 lb):
• Consume 12 to 15 kg (26 to 33 lb) of bamboo leaves and stems, or 23 to 38 kg (50 to 84 lb) of bamboo shoots per day (Pan and Lü 1993)
• Eating a lot of food quickly compensates for a diet that is not energy or nutritionally dense (Schaller et al. 1985)
• Handle and process foods quickly (break, crush, chew, swallow) (Schaller et al. 1985)
• Also see “Digestion and scat”
• Select bamboo to maximize nutrient intake (Hu and Wei 2004)
• Prefer high-quality bamboo plants (Swaisgood, Wang, et al. 2016)
• Select nutritious parts of bamboo plants (Swaisgood, Wang, et al. 2016)
• Pandas change where they forage and on what bamboo species they eat to improve their nutrition, seeking out protein, amino acids, minerals, etc. (Hu and Wei 2004; Nie et al. 2015)
• Eat different parts of bamboo plants at different times of year (Garshelis 2009b)
• Eat different species of bamboo growing at different elevations, during different seasons (Garshelis 2009b)
• Depends on the bamboo’s growth stage (Garshelis 2009b)
• See “Seasonal changes in feeding,” below
• Panda populations in the wild may be most influenced (and growth limited) by the seasonal availability of nutrient-rich bamboo leaves (Li et al. 2017)

Other diet items (rarely eaten)

• Plants other than bamboo
• Eat from herbs, vines, shrubs, trees (Chu and Long 1983, cited by Schaller et al. 1985; Schaller et al. 1985)
• Consume leaves, stems, roots, fruits, and barks in very small amounts (Morris and Morris 1966; Chorn and Hoffman 1978 citing Giant Panda Expedition 1974; Schaller et al. 1985; Hu and Wei 2004; Garshelis 2009b)
• Meat and carrion (dead animals)
• Appears to be opportunistic
• Small animals, such as rodents (Garshelis 2009b)
• Opportunistically scavenge on dead hooved animals (deer, boar) (Hu and Wei 2004; Garshelis 2009b)
• Eat animal bones and hides (Long et al. 2004)
• Feed on pig bones thrown away by humans (Long et al. 2004)
• Eating carrion and bones most commonly observed in pregnant or lactating females, according to Long et al. (2004)
• May have nutritional benefits (eg, additional vitamins), but needs more research (Long et al. 2004)
• Sand or soil
• Observed, but rare (Long et al. 2004)
• Perhaps for absorbing plant toxins or for mineral content (Long et al. 2004)
• Crops (if bamboo is scarce) (Hu and Wei 2004; Garshelis 2009b)
• Eat crops, including pumpkin, beans, wheat [reported from Minshan range] (Hu and Wei 2004)
• Some individuals seek crops out, even when bamboo is available (Garshelis 2009b)
• Domestic animal feeds
• Observed to eat pig food (Hu and Wei 2004)
• Human trash (food waste) (Garshelis 2009b)
• Some individuals seek out, even when bamboo is available (Garshelis 2009b)

Feeding behavior

• Activity patterns
• Spend more than 50% of their time foraging (Swaisgood, Wang, et al. 2016)
• Feed up to 14 hours per day (Pan and Lü 1993)
• Also see Behavior
• Plant choice
• Select bamboo stems in diameters that are easy to hold and chew (Garshelis 2009b)
• Body posture
• Usually sit or recline on haunches, leaving feet free to hold/manipulate bamboo (Chorn and Hoffman 1978; Schaller et al. 1985; Garshelis 2009b)
• Adaptations
• With front feet, grasp bamboo leaves or stem between palm and thumb-like digit (e.g., Jones 1939; Endo et al. 1999)
• Grasp bamboo stalk with teeth and insert into corner of mouth (Schaller et al. 1985; Garshelis 2009b)
• Then repeatedly bite off sections, about 2 to 5 cm long
• Move forepaws up and down to help break the stem (Schaller et al. 1985)
• Chew little (Garshelis 2009b)
• Strong teeth tear off tough outer layer of bamboo stem and back molars grind down (Chorn and Hoffman 1978)
• Also see Front feet

Seasonal changes in feeding

• Parts of bamboo
• Shift between eating leaves and shoots, and stems and branches (Garshelis 2009b)
• Quality and amount of high-quality bamboo available to eat changes seasonally (Swaisgood et al. 2016; Li et al. 2017)
• Prefer shoots, when seasonally available in spring; later, eat leaves (Swaisgood, Wang, et al. 2016)
• Stems eaten more commonly during winter, when less bamboo available (Swaisgood, Wang, et al. 2016)
• Spend more time foraging in late winter and early spring, when good-quality bamboo is scarcer (Li et al. 2017)
• Also see Bamboo, above

Drinking

• Frequency of water consumption
• Not well studied
• Yong (1981) (cited by Schaller et al. 1985) concluded that giant pandas drink at least once per day; based on limited evidence
• Water sources
• Streams, pools, and puddles (Schaller et al. 1985)
• Water lost through feces; pandas must replace water through drinking or bamboo with a high water content (during rainy season) (Schaller et al. 1985)

Digestion and scat

• Gut anatomy
• Stomach
• Simple in structure (see Loeffler et al. 2006)
• “Thick-walled and muscular, almost gizzard-like” (Chorn and Hoffman 1978)
• Intestines
• Remarkably short for an herbivore (Loeffler et al. 2006)
• Only about 4 to 5 times its body length (Chorn and Hoffman 1978; Loeffler et al. 2006)
• Length more similar to that of meat-eating carnivores than herbivores (Loeffler et al. 2006)
• Little differentiation (separation) between small and large intestines (Loeffler et al. 2006)
• Digestion
• Digestive tract adapted for extracting bamboo cell contents quickly (Chorn and Hoffman 1978; Schaller et al. 1985)
• Do not digest plant cell fibers or cell walls, as other herbivores do (Loeffler et al. 2006; Li et al. 2010)
• Difficult for giant pandas to digest cellulose (Zhu et al. 2011)
• Physical adaptations, plus gut microbes, allow pandas to live on a mostly bamboo diet (eg, Zhu et al. 2011)
• Gut passage time
• Food not retained in digestive tract for long (Schaller et al. 1985)
• Takes food about 5 to 13 hours to pass through (Schaller et al. 1985)

Nearly 99% of a giant panda's diet is bamboo.

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

Hu & Wei (2004)
Pan & Lü (1993)
Schaller et al. (1985)
Li et al. (2017)