PANDA REPRODUCTION AND CUB RAISING

PANDA BREEDING

Infant and mother In the wild, pandas generally don't have any problem breeding. A female panda usually mates with the dominate male in her range and sometimes after she mates she has to climb trees to get away from other male pursuers.

Females reach sexual maturity when they are around five; males when they are around six or seven. Females generally give birth three or four times in their lifetime but can be able to reproduce for more than 10 years. It appears to be a myth that pandas are lousy lovers. A long-term field project, run by Chinese scientists, according to The Telegraph, has revealed that they are actually extremely good at reproduction. According to Chinese scientists: “In the wild, the female giant pandas will be first in heat at the age of 6.5 years old, and they won't mate and give birth to babies until they are 7.5 years old. The pandas bred in captivity will be premature. They can begin to "have a love affair" at the age of 3.5, "get married" and give birth to baby pandas at the age of 4.5. [Source: Science Museum of China kepu.net.cn]

Female pandas can only conceive during their three or four day day estrous period, which occurs just once a year in the spring. The nonprofit organization Pandas International says that females are fertile for just 24 to 36 hours a year. They are reported to be very choosy when selected a mate. Females giver birth are about the same rate as North American brown bears: once every other year for about 15 years. Males have extremely small penises and this contributes to low insemination rates in the wild. Only one in five panda females are capable of producing fully developed ova at a given time. Sometimes male pandas fight for the chance to mate with available females. Dominant males often fight to control four or five females. When a fight occurs the female often climbs a tree and waits until one of the male emerges victorious.

Panda Courting

Pandas usually mate in the spring. Females usually go into heat in April and they are generally only fertile for about 72 hours. They indicate their readiness to mate with moans, bleats and barks. Males gather, chase and fight each other for access to females. In the weeks before a female becomes receptive she is very restless, endlessly rolling and rubbing the ground, bathing more than other times. She chirps, bleats and grunts more and leaves here scent by running around constantly. Her nipples and genitals begin to swell and redden.

When a female is receptive she advertises the fact through emitting a distinctive sound, scattering chemical signals in her urine in bamboo thickets and forests over a large area, and rubbing a gland near her tail against the ground to deposit a sticky substance with an odor detectable to other pandas. Her sexual organs change color: turning red, then white. High estrogen levels in her urine indicate she is fertile.

Females usually wait in an area for males to arrive and often mate with several males. Chinese naturalist Pan Wenshi of Beijing University told National Geographic, "In the Qin Ling mountains, individuals of both sexes coexist in areas usually covering about two square miles. But before spring mating, males expand their ranges to about five square miles, encompassing the area of several females. A dominant male may control his mating grounds for three or four years. Most other males keep their distance, and combat is rare."

Courting information includes: 1) scent information — a smear of the secretion of the circumanal gland onto the basal of the trunk, onto the stones or the extrusive ground as the scent sign; 2) auditory information — at different stages of the courting process are marked by different sounds that include “love songs” of the giant pandas on the ground or in the trees to attract attention; 3) visual information — to attract the attention of a partner includes restlessness and grasping and biting branches and leaving clear marks on the trees and gnaws on branches. [Source: Science Museum of China kepu.net.cn]

Panda Mating

Pandas often mate while frolicking in the snow in March or April. The panda courting ritual involves chasing one another around and up trees. The female performs a strange kind of backward walking in which she backs up a few steps and tosses and shakes her head. As the time to mate nears the female becomes more passive and even makes advances to the male with her tail up and her head down. If the male doesn’t respond she may fall onto to her back and raise her paws playfully to attract his attention.

The mating of the giant pandas often takes place on mountain slopes or in clearing. Some giant pandas mate in the trees. The noises they make are mainly baas or chirps. During copulation the male stands almost upright behind the female who is on all four with her rear up and her head slightly down. The male bleats and makes mouthing gestures and mounts and dismounts numerous times before actually completing the act. One group of researchers counted 48 mounts in a three day period, with only one four-minute intromission during that time. After a day or two of this the pandas separate and return to their solitary lives.

Usual panda mating ranges from 30 seconds to five minutes, experts say. Even though the penis of an adult giant panda males is only about three centimeters long with pandas size matters. One male 150-kilogram male panda at a zoo in Chiang Mai, Thailand was deemed too fat to mate with a 115-kilogram female at the zoo and put on a diet of bamboo leaves. It has been estimated that in the wild only 28.6 of adult giant pandas produce offspring. This is mainly because only a few of them can mate under natural circumstances.

Panda Sex Stamina Record — 18-Minutes

In April 2015, a male “Lu Lu, a male panda, broke records for longest known panda mating session. A live stream of his achievement was widely watched in China, where he was given the nickname "Enduring Brother." William Wan wrote in the Washington Post: “The video of his 18-minutes-and-3-second romp has gone viral in China, with bloggers praising the panda named Lu Lu for his enthusiasm, technique and — above all else — stamina. [Source: William Wan, Washington Post, April 6, 2015]

“Lu Lu — a bear Chinese scientists rescued from the wild in 1999 — set the first of his two recent records late last month. His passionate encounter with a female named Zhen Zhen lasted 7 minutes and 45 seconds, according to experts at the China Research and Conservation Center of the Giant Panda in Sichuan. “Lu Lu's accomplishment was hailed far and wide, including the Communist Party's flagship paper People's Daily. But that was all just prelude, it turns out, to his even greater record-shattering performance just a few days later.

“This time around it was with a female named Xi Mei. Xi Mei has a good record as mate, having given birth to eight cubs since 2005. At first, scientists tried to set her up with another male panda named Yi Bao because the two on paper shared such genetic compatibility. But when the time came, Yi Bao couldn't be less interested. They brought in a second male, named Bai Yang, who turned out even worse, outright attacking Xi Mei. A zookeeper had to pour cold water simply to separate the two. So in the end, scientists turned to their stud-in-residence: Lu Lu.

““Like humans, animals have feelings too," the scientists noted in a surprisingly animated live posting on Chinese social media as Lu Lu's session began. "Xi Mei is a bit timid and seems to be avoiding," they posted, as if still traumatized by the earlier attack. "Lu Lu is very respectful, although hesitant. After calming down for a while, he finally decided to stay by Xi Mei's side! Applause for the brave Xi Mei and the gentle Lu Lu!”

“The two soon launched into an 18-minute marathon that Chinese officials would later describe in restrained terms simply as "quite successful." And because the zoo officials had just set up a "iPanda Channel" to live stream their pandas, Lu Lu's record-breaking sexual exploits were on full display to the world.

Pregnant Pandas and Floating Eggs

The gestation period for a giant panda ranges from 80 days to 200 days, with an average of around 160 days. A fertilized panda egg becomes a 16-cell embryo which free-floats in the womb for one to five months before attaching itself to the wall of the uterus. The period is much longer than for other mammals (that usually have eggs that attach to the wall right away) and make artificial insemination difficult. It is very difficult to tell if a giant panda is pregnant because females give many false signs.

Panda experts that it is impossible to accurately predict when a cub will be born because fertilized eggs often float in the womb for a while and there is no firm time for implantation. The egg only attaches to the wall 45 days before the cub’s birth. Some scientist say the reason for this is that pandas take in so little nutrients that they can’t support the fetus for much longer than 45 days. This also explains why panda’s are so small when they are born.

After becoming pregnant a female make a den in a hollowed-out standing tree or cave, where she usually gives birth. After three to five months of pregnancy, often in early autumn, the giant panda mother begins to ill look for a dark and windless place for a den. To prepare, to prepare for the birth she often makes a bed with dry bamboo leaves.

Sometime nonpregnant females go through “pseudo-pregnancies" in which they display behavioral and hormonal changes similar to a pregnant female but are not pregnant. Sometimes when observers think captive female pandas are pregnant, there are in fact just hungry. The phenomena is referred to by scientists as “phantom pregnancy”. One expert at the panda center in Chengdu told AFP, “pregnant pandas receive more buns, fruits and bamboo, so some clever pandas have used this to their advantage to improve their quality of life.”

Panda Births and Newborn Cubs

A female usually gives birth in her den in a hollowed-out standing tree or cave, sometimes letting out a loud squawk when an infant is born. At birth infant pandas weigh only 100 grams (ranging from 36 to 200 grams, roughly one to seven ) and are bleating, pink and hairless and look like tiny, pink, blind mice. A three-day-old panda cub is smaller than a human hand and weighs less than a coffee cup. No other non-marsupial animal gives birth to smaller offspring in relation to its size.

A newborn panda cub is very vulnerable. Its eyes are closed and has a red body sparsely covered with white hair. Weak and slim, the cub cannot even stand by itself. The average new-born weight of a cub is about 1/1,000 its mother's weight. In any other species it would be a premature delivery. Except kangaroos, no other mammal has such a weak cub. But at least a kangaroo baby has a poach. A panda cub is exposed and would soon die without its mother. You can also see how difficult it is for a mother to raise a cub to its maturity [Source: Science Museum of China kepu.net.cn]

Females usually give birth to panda cubs in September or October. Often one cub is born; sometimes two are; and rarely three. Many panda females give birth to twins. Because one infant requires so much attention, the mother generally chooses one of the twins and let the other die. Mothers often decide within minutes after birth which one they keep and which they reject. One fieldwork study uncovered a dead cub near a mother that was taking care of a healthy cub. Even for the chosen cub the survival chances are not that good. Many pandas die young.

Infant pandas spend much of their first year of life in their dens, on a floor cushioned with pine boughs. Young pandas generally do not begin walking around until they are four months. At six months they weigh around 22 pounds and are able to climb trees and play with their mother. At the age of nine months, young pandas weigh about 50 pounds and are agile tree climbers.

Infant Pandas and Their Mothers

After a panda cub is born the mother doesn't leave its side — neither eating, drinking or defecating — for a period of five to 25 days. A typical, captive, panda mother will stay with her infant straight for seven days and then leave just for three minutes to get a drink, and not leave to eat for 17 days. Panda infant are vulnerable to cold, rain and attacks from martens, leopards and black bears.

The pregnant female eats a lot of bamboo to store nutrition for the birth and raising the cub. She raises the cub in the den after birth, only leaving to defecate and pee. The panda mother almost always has the cub in her arms, warming it with her body, kissing and licking it until it can walk by itself. Only when the cub reaches the age of one month does she venture out for food and drink — but only for short periods of time.[Source: Science Museum of China kepu.net.cn]

The infants are very small and delicate and are easily crushed by their 200-pound mothers, who handle their young with extraordinary gentleness. Much of the time the mother cradles the infant against her chest. After the crucial 5 to 25 day period is over the mother leaves for hours at a time to eat and regain her strength. This behavior was originally thought to be abandonment.

Young Panda Cubs

Newborn pandas are about 18 centimeters long. Since they are born in a premature state, it is hard to identify the gender even after birth. Newborn cubs are so small and delicate they can easily be crushed under the much larger mother. They can cry quite loudly for such small creatures. At one week black patches appear on the skin. At two weeks black hairs begin to grow. Infant pandas spend their time crying, sleeping and suckling. At three weeks, baby pandas begins to crawl. At one month the eyes start to open and they are better at regulating their own body temperature. At two months baby pandas stop crying and suckle three to four times a day. [Source: Washington Post, September 2012]

Pandas develop their patches of distinctive white and black fur at about two weeks and reach the weight of a half a kilogram (a pound) after three weeks. At about six weeks the cubs weigh around two kilograms (four or five pounds). Their teeth emerge at four weeks, their eyes open at around seven weeks, and their nose turns from pink to black at six months. When they reach the age of two months they are cute white and black fur balls that weigh between two and five kilograms (five and 12 pounds).

Young pandas sleep a lot and do not begin eating bamboo until they are around one year old. They begin crawling around four months and usually nurse for about a year but may nurse until they are 1½ years old. The mothers often have to eat for 14 hours a day to produce enough milk. At the age of nine months cubs begin chewing on bamboo shoots just for practice. As they develop they flip around from back to front; makes puppy-like cries; and leave scent markings.

Panda Cub Growth

At three months young pandas can stand and walk a little; teeth are emerging; eyesight and hearing are improving; and they suckle two to three times a day. At four months their activity increases and they climbs on their mother’s back to play. At five months young pandas trot behind their mother; imitate her eating bamboo; and climb and sit in trees. At six months they begins to eat solid food and suckle one to two times a day. At one year young pandas lose their baby teeth. At two years young pandas in the wild leave their mother and begins fending for themselves.

When the cub reaches three month of age, the young cub can walk and has normal eyesight. In the spring, the weight of a six–month-old cub has reached to about 13 kilograms. At this period, the cub begins to learn how to eat bamboo and how to live alone in the wild. The cub also drinks milk for nutrition sometimes.

In the wild the cub stays in the den for four to six weeks and then rides on mothers back and ambles along side her at six months. It is believed its mother teaches the cub how to defend itself — mostly against other pandas — and locate the best arrow bamboo. Captive adolescent pandas are quite active and social. Ones at Wolong climb trees, wrestle, hang from branches, fall off branches, push each other off rocks, wack each other in the head.

Adolescent pandas often sleep in the safety of trees while their mother forage for food. Sometimes the mother will leave them alone for as long as 52 hours. In the past young pandas found by researchers or hikers were believed to have been abandoned. At one time 35 of the 113 pandas in China’s captive breeding program were "rescued" in the wild. An effort is being made to stop this practice since in all likelihood most of these were cubs seeking safety while their mothers were foraging.

Adolescent Pandas

The weight of a panda cub reaches over 50 kilograms when he/she is one and a half years old. At this time, the cub says goodbye to his/her mother and begins to live independently. Free from hard work of pregnancy and baby caring, the panda mother could once again "fall in love" and "get married".

Panda cubs may stay with their mothers for more than two years. At the age of 18 months young pandas weigh about 120 pounds and are nearing the size of their mothers. Sometimes when a young panda is at this age, it is left to fend for itself after the mother mates. Other times pandas cubs have been observed living with their mothers before they mates and then leave.

Pandas are regarded as adult when they reach sexual maturity around the age of 5 years old.

Image Sources: Panda images: WWF and CNTO; Red Panda images: ailarus

Text Sources: New York Times, Washington Post, Los Angeles Times, Times of London, National Geographic, The New Yorker, Time, Newsweek, Reuters, AP, Lonely Planet Guides, Compton’s Encyclopedia and various books and other publications.

Last updated July 2022