By Dr. Becker
Giant pandas, with their striking black-and-white fur and irresistibly cuddly appearance, are one of the most beloved bears in the world. They're also among the most at risk. With only an estimated 1,864 giant pandas left in the wild,1 and about 100 living in zoos, these animals are critically endangered.
While researchers have been able to observe giant pandas' behavior in zoos, they are rarely spotted in the wild. Giant pandas live only in mountainous regions in China, where they spend their days in the high bamboo forests, munching on their favorite food (bamboo).
Giant pandas may climb to elevations up to 13,000 feet. Because they're so elusive, little is known about how giant pandas behave in the wild – a crucial piece of the puzzle to helping prevent their potential extinction. As noted in the Journal of Mammalogy:2
"One of the most fundamental questions in animal ecology concerns the activity patterns of animals and the environmental and intrinsic factors that influence such dynamics. Activity patterns of the elusive and endangered giant panda (Ailuropoda melanoleuca) are not well understood."
GPS Collars Reveal Surprising Facts About Giant Pandas — They're Not Really Solitary!
Researchers from Michigan State University placed GPS collars on five giant pandas living at the Wolong Nature Reserve in China. The pandas were then allowed to roam freely, giving researchers an inside glimpse into their behavior. Study co-author Jindong Zhang told Discovery News:3
"This was a great opportunity to get a peek into the panda's secretive society that has been closed off to us in the past."
Giant pandas have long been considered solitary creatures, but the new study suggests otherwise. Two of the adult female pandas spent long periods of time together, along with another young female panda.
There was one adult male in the group, and he traveled widely but came back to check on the females often. He regularly marked trees with his scent as he came and went. The giant pandas also had about 30 different areas where they liked to eat bamboo.
Once the bamboo was gone in one area, they'd move on to the next. However, every six months or so, they would travel back to past dining spots, likely because they were anticipating the bamboo's regrowth.
They may also revisit certain locations due to communications with nearby pandas, although this is still being explored.
How Do Giant Pandas Survive on Only Bamboo?
Bamboo is a woody, low-nutrient plant, presenting a quandary of how it's able to sustain giant pandas, who eat it exclusively. Adding to the conundrum, the bacteria living in the pandas' digestive tract have relatively few strains that are helpful in digesting fibrous plants like bamboo.
Instead, surprisingly, most of the pandas' gut microbiome consists of bacteria normally found in meat-eaters.4 Another study using GPS trackers may shed some light on the issue.
Researchers from the Chinese Academy of Sciences in Beijing analyzed chemicals excreted in the feces of five captive and three wild giant pandas. The analysis revealed pandas expend only 38 percent of the energy a typical animal of that size would expend.5
Only the Australian rock rat and the golden mole are known to expend less energy than the giant panda. According to senior author Fuwen Wei, a professor of zoology, in Discovery News:6
"We thought the metabolism of the panda would be low because the bamboo diet contains low energy … But it is very surprising that it is this exceptionally low, equal to the three-toed sloth, and much lower than the koala."
The pandas conserve their energy in a number of ways, including:
- Not moving much: Captive pandas move around about one-third of their day, wild pandas about one-half
- Moving slowly: When giant pandas move around it is very slow, about 50 feet an hour
- Smaller organs, including the brain, liver and kidneys, relative to their size: Smaller organs require less energy to function
- Low levels of thyroid hormones: Captive giant pandas have about half the level of thyroid hormones that regulate metabolism than other animals of similar size (even lower levels than found in hibernating black bears).
The pandas' thyroid hormone levels were similar to those of the gray seal, which conserves energy while diving by lowering its metabolism.
According to the study, which was published in the journal Science:7
"A giant panda–unique mutation in the DUOX2 gene, critical for thyroid hormone synthesis, might explain these low thyroid hormone levels. A combination of morphological, behavioral, physiological, and genetic adaptations, lead."
Giant Pandas Are the Rarest Bears on the Planet
Understanding more about how giant pandas live and what makes them thrive is important for their conservation.
Giant pandas play an important role in the bamboo forests, helping to spread seeds and promote the growth of vegetation in areas home to many wildlife species (some endangered), like the golden monkey and crested ibis.
Habitat loss is one of the greatest threats facing the pandas. Not only are roads and railways invading their native homeland (which may prevent the animals from mating), but the forest is also being destroyed, putting their access to bamboo at risk.
According to the World Wildlife Fund (WWF), more than 50 panda reserves have been established in China, but only 61 percent of the country's wild pandas are protected by these areas.8