Giant pandas turn out to be a lot more social - and flirtatious - than anyone had ever imagined, according to new research.
The study, published in the latest issue of the Journal of Mammalogy, provides evidence that the iconic black and white bears are not always solitary creatures, as was once thought, but instead have rich and complex social lives.
"Pandas are such an elusive species and it's very hard to observe them in wild, so we haven't had a good picture of where they are from one day to the next," co-author Vanessa Hull of Michigan State University said in a press release.
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Hull and her colleagues placed GPS collars on five giant pandas at the Wolong Nature Reserve in China. Caretakers there have named the pandas: Pan Pan, Mei Mei and Zhong Zhong (three adult females), Long Long (a young female), and Chuan Chuan (a male).
The pandas, wearing their new high tech bling, were released back into the reserve.
"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," co-author Jindong Zhang said.
Hull added, "Once we got all the data in the computer we could see where they go and map it. It was so fascinating to sit down and watch their whole year unfold before you like a little window into their world."
The researchers determined that two of the adult females, Chuan Chuan and Mei Mei, hung out together for long periods during the fall and outside of the spring mating season. With them was little Long Long, the young female panda.
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As for the male Chuan Chuan, he traveled much more than the females did, but frequently came back to check on them. As he did so, he would advertise his presence with scent marking, meaning that he rubbed his smelly glands against nearby trees. The females seemed loyal to him, so the smell was definitely not a turn off.
Could male pandas in the wild keep harems? The researchers are still learning about giant panda sex lives. The Chinese government is protective of its endangered pandas, and for more than a decade banned putting GPS collars on them, so data is still relatively scarce.
From this latest study, the scientists also found that pandas spend a lot of time munching bamboo in up to 30 favorite areas.
"They pretty much sit down and eat their way out of an area, but then need to move on to the next place," Hull explained.
The GPS tracking revealed that the five pandas returned to their favorite dining spots after being gone for long spans of time, up to six months. This suggests that they remember successful feasting experiences, and return in anticipation of regrowth.
The researchers add that specific locations may also have other importance for pandas to return to if the bears are communicating with neighboring pandas at certain vantage points.
While the wild panda population has increased nearly 17 percent to 1,864 pandas, the bears are still threatened by habitat fragmentation, human impacts and climate change.
Photo: Giant panda eating bamboo, Credit: Chen Wu, Wikimedia Commons
While the giant panda is known for its finicky breeding habits in captivity, its distantly-related cousin, the red panda is known to breed particularly well in zoo. As such, the Smithsonian National Zoo welcomed four red panda cubs this summer -- bringing the total number of red panda births here to more than 100 cubs since 1962. But while the zoo is celebrating these bright-eyed and bushy-tailed arrivals, they're also suffering a bit of disappointment. Staff had suspected the zoo's resident giant panda, Mei Xiang, was pregnant; but the hormonal fluctuations they had been monitoring turned out to be merely signs of a false pregnancy.
Two of the cubs were born at the National Zoo and two more were born at the zoo's sister facility in Virginia. All four cubs are female. The two pictured above are the offspring of the National Zoo's proud red panda parents, Shama and Tate. Shama gave birth in her den on June 17. When she didn't respond to the usual calls from zoo keepers, the staff suspected that she had given birth. A quiet squeal from the den was the first hint of cubs. But it would take another week before the zoo keepers were able to do a "cub check" to confirm.
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Tiny from birth, red pandas generally grow to be seven to 14 pounds. In comparison, giant pandas grow to about 200 pounds. These cubs will spend the next 90 days in the den and won't leave their mothers for up to year. Red pandas are considered a vulnerable species by the International Union for Conservation of Nature. There are estimates that the mature wild population is as low as 2,500 individuals.
The red panda's particularly bushy tail helps it stay balanced as it climbs trees. And, while it's predominantly a reddish-brown color to match its surroundings, it inhabits some of same territories as the giant panda: China, the Himalayas, and Myanmar. They also have a similar diet -- with a few additions. Red pandas mainly feast on bamboo but also eat berries, blossoms, and bird eggs, according to the National Zoo.
Veterinarians are careful to wear gloves and take necessary precautions when handling the cubs. Many times staff will wear a second set of gloves that have been rubbed with nesting material and the mother's feces in order to cover their own human scent. Each of the cubs has gotten a clean bill of health from zoo veterinarians.
Mei Xiang, the zoo's female giant panda had her sixth psuedopregnancy -- a common occurrance for pandas. Mature pandas ovulate once a year and either conceive or don't, but they still experience the same signs of pregancy: decreased appetite, excessive grooming and spending more time in the den. Mei Xiang had also been showing signs of hormonal changes in her urine, but veterinarians had been unable to observe a fetus during ultrasound exams. Now, after several weeks of her hormone levels declining, zoo keepers can officially declare it a psuedopregnancy. Panda births are rare in captivity. Mei Xiang gave birth to one cub in 2005.
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