Polar Bear Facts

Tag: Polar Bear Cubs

  • How often Do Polar Bears have Cubs? – Polar Bear Giving Birth

    In this article we are going to discuss about polar bear giving birth to its cubs as well as the bear’s birth interval.

    How often Do Polar Bears have Cubs?

    Studies indicate that most females wean their cubs after two and a half years, which suggests that they can afford to mate once every three years. According to scientists, the female bears inhabiting Beaufort Sea are thought to mature earlier than those living in other areas. The weaning time and the birth interval of Beaufort Sea population is the same.

    In 1990s

    In rare instances, scientists have also observed female polar bears keeping their babies for as long as three and a half years. In the 1990s, a few individuals reported to wean after three and a half years in the Viscount Melville Sound. Even so, another female reported to have her cubs around her for up to four and a half years. According to Ian Stirling the likely reason could be that bears were probably living in less productive habitats where multiyear sea ice didn’t occur as much. Plus, the ringed seals weren’t abundant in the Viscount Melville Sound. As it turns out, a less accessible food might have probably slowed the growth rate of polar bear cubs, resulting in a delay in the age at weaning.

    Another explanation for the delay in weaning (in 1990s) could be due to overharvesting in adult males. The adult males could have been less frequent which would drive away the cubs from their mother. However, Viscount Melville Sound isn’t protected by multiyear sea ice anymore perhaps due to climate change therefore; polar bears can afford to hunt ringed seals.

    In 1980s

    If we go back to the 1980s we observe 40% of all polar bear females could successfully wean their cubs at only one and a half years of age in the western coast of Hudson Bay. As it turned out, nearly all females would breed every two years which may have allowed them to produce 30% more litters in their entire lives.

    Nonetheless, when scientists compared the mortality rate in yearlings that were weaned right on time against those which took additional time, they found interestingly no major difference. Both had lived more than their average lifespans. They also observed that the survival rate of one-year-old cubs in the Hudson Bay was probably the same as that of two-year-old cubs inhabiting rest of the Arctic.

    Why the Hudson Bay Females are more Productive than others

    1. Studies indicate that some of the females in the western coast of Hudson Bay have successfully raised their cubs so that the yearlings hunt on their own. The reason behind is that the snowdrifts in the Hudson Bay melts relatively earlier, and as it softens, the yearlings which are probably not too heavy to break the ice, can hunt ringed seals at their breathing holes.
    2. Another reason as to why Hudson Bay females produce more frequently than others is that the Hudson Bay itself is biologically productive. The rivers that end up with the Hudson are thought to bring many nutrients which indeed attracts large seal population. Since they are the primary food of arctic bears, the bears of all ages might have less difficulty catching food.
    3. Studies have also shown that the Hudson Bay is home to a large number of bearded seals. The bearded seal is nearly five times the size of a ringed seal. The larger food source means larger carrion remaining on the sea ice. Yearlings often find it hard to hunt and so they mostly rely on left-over carrion. They are going to eat seals by scavenging the kills until they are big enough to hunt on their own

  • Polar Bear Cubs Facts – Interesting Facts about Baby Polar Bears

    We have gathered some of the most amazing and unbelievable polar bear cubs facts which you probably don’t know. Just to let you know that all these facts about baby polar bears are real. Although polar bears are one of the largest land carnivores in the world yet baby polar bears are only the size of a ground squirrel when they are born. However they will grow pretty fast in the first couple of months. Let’s take a look at the baby polar bear facts.

    Polar Bear Cubs Facts

    Polar Bear Cubs have Fluffy Furs

    The cubs are well protected with fluffy white fur even when they are only weeks old. While polar bear cubs can survive the frigid arctic weather they are most likely suffer from hypothermia if they get wet. Therefore, mother bear doesn’t encourage her cubs to swim longer distances.

    Polar Bear Cubs can Climb Trees

    Believe it or not, baby polar bears can climb trees. Although there are very few trees in the Arctic but when a polar bear family gets close to the trees, the cubs often climb up the trees during playing. Adult male or a female bear cannot climb for they are too heavy to lift their weight.

    Polar Bear Cubs Mimic their Mother

    Baby polar bears are often seen mimicking their mother, it’s like monkey see monkey do. They will try to drink water, eat food, or stretch in a way their mothers do. The cub’s mimicking habits probably makes easy for their mother to teach them hunting techniques.

    Polar Bear Cubs are Curious

    Baby polar bears are highly curious especially in the first six months. They will wander far from mom and each day they likely bring about a bit more independence. However, cubs rarely go too far from their den and also their mother mostly keeps a close eye on them.

    Polar Bear Cubs’ Weight

    The average weight of captive polar bear cubs is somewhere in between 570 grams and 750 grams (1.2 to 1.6 lbs) at birth. In the wild habitat, they often hardly weigh more than a pound at birth. However, they will attain 7.7 pounds in just 30 days after birth.

    Polar Bear Cubs Stay Inside the Den

    They will stay inside the den for as long as 60 days after birth. While maternity den the polar bear cubs not only stay safe from predators, they also get warm. Once they reach 2-months age, they will leave the den. By the time baby polar bears leave their dens, they weigh 10 – 15 kg (22 – 33 pounds).

    Polar Bear Cubs are Born Blind

    Baby polar bears are completely helpless and they are blind at birth. They are highly vulnerable to potential predators at this stage. Arctic foxes usually hunt baby polar bears inside the den.

  • How Many Babies Can a Polar Bear Have? – Polar Bear Litter Size

    Do you have any idea how many babies do polar bears have at a time? In this article, we’ll try to explain just about anything on the reproductive biology of polar bears. The polar bear litter size generally depends on quite many things which is why each polar bear population has its own litter size. Twins are common throughout much of the polar bear range. Triplets are extremely rare.

    How Many Babies Can a Polar Bear have?

    Ian Stirling, a leading polar bear scientist, suggests that more than two-thirds of the litters consist of twins. It’s fairly common for a female polar bear to produce two cubs at time. While twins are almost the norm, about 20% to 30% of the polar bear’s reproduction produces a single cub.

    Scientists have rarely observed triplets because the litter size generally depends not only on the time frame—it also rests on the geographic distribution. In 1908s, Ian Stirling had examined 119 litter sizes in the Western Hudson Bay out of which 20% mainly consisted of twins; only 12% were triplets, and he witnessed a single case of four cubs.

    When scientists examined the litter sizes in the Canadian High Arctic, Svalbard, Beaufort Sea, and the Baffin Island, they observed that only 1 to 3% of all litters were triplets.

    However, when scientists examined the litter sizes in the Canadian High Arctic, Svalbard, Beaufort Sea, and the Baffin Island, they observed that only 1 to 3% of all litters were triplets. The litter sizes in these areas were four times lesser than the one observed in the Hudson Bay.

    Over the past 15 years, the triplets have become less frequent as they were in 1980s. They are still recorded nevertheless.

    Read More: Polar Bear Cub

    A mother polar bear with her twins. How many babies can a polar bear have?. Photo by Arctic Mission

    What are the Factors that Determine the Polar Bear Litter Size?

    It’s a pretty tough ask to measure the polar bear litter sizes because scientists mostly count when polar bear cubs emerge from the dens. They just can’t find out how many cubs are unable to make it outside the den before they are weaned. Scientists do however aware that the litter size might be greater than they initially anticipated since a few cubs likely die of natural causes inside the den.

    Read More: How Do Polar Bears Reproduce?

    The average number of polar bear babies in the spring season ranges from 1.5 to 1.9 depending on the location. Andrew Derocher, a leading polar bear researcher, claims that there seems to be no real relation between the litter sizes and latitude. It is quite possible that different litter sizes are observed in different time periods. Therefore, it is logical to assume that the litter sizes primarily depend on the availability of food as well as other environmental conditions instead of latitude. As a rule of thumb, the litter size decreases as more cubs die naturally. Still, scientists find it pretty hard to measure the original litter size when they see a female polar bear with her cub. That single cub doesn’t tell anything about its siblings which might have possibly died before weaning.

    In the winter of 1937, Father Van de Valde had obtained data on the polar bear litter sizes from various sites he traveled along the way. He observed the average litter size of 1.88 to 2.0 cubs from December to February.

    In 1970s, the largest litter sizes were recorded long the southwestern coastlines of Hudson Bay. Dick Robertson and Dale Cross had observed the litter sizes from the air. The average litter size was found to be 2.0 which were probably the greatest. Paul Prevet and George Kolenosky also tracked polar bears along the northern Ontario coast somewhere between 1974 and 1978. They also found the litter size to be 2.0.

    How Many Babies Can a Polar Bear have? – Video

  • When Do Polar Bear Cubs Leave their Mother?

    In this article we’ll be studying how long do polar bear cubs stay with their mom and when do they leave her. Female polar bear is an extremely dedicated mother in that she prefers to have cubs around her for as long as 2 to 3 years after birth. That’s a pretty long period isn’t it? During the long nursing period, the mother teaches her cubs just about everything including hunting and swimming. Let’s see when do baby polar bears leave their mother.

    When Do Polar Bear Cubs Leave their Mother?

    The typical weaning period of polar bear cubs is about 2.5 years but it also varies. Sometimes the cubs leave their mother around 2 years while at others they wean later than 2.5 years. But normally cubs will stay with their mother for no more than 2.5 years.

    Sometimes it so happens that a female polar bear doesn’t find her mating partner when the time is due. In that case, the cub likely stays with its mother until the mother actually abandons it herself. Researchers have yet to understand fully the phenomenon of weaning yearlings in polar bears. It’s pretty challenging for a mother to wean her present cubs for she must prepare herself for another litter by storing enough fats.

    How Does the Mother Decide to Leave her Cubs?

    It depends on numerous factors such as;

    • The size of offspring;
    • Availability of food;
    • Maternal condition, and
    • Willingness of a mating partner.

    The mother bear assesses all the above factors to decide for the ideal weaning time. When the mother is in estrous, the adult male likely chases the young and attempts to drive it away from her mother. The young polar bear soon learns that it’s time to live an independent life on its own as it is no longer wanted.

    Read More: How Do Polar Bears Reproduce?

    A mother walks alongside her cubs. When do polar bear cubs stay with their mother? Photo by Natural World Safaris
    • While it may seem odd in the first place the family break-up is quite natural in polar bears. Cubs play, fight, and eat under the watchful eye of their mother until they come of age by which they’ll gain independence.
    • When they attain 2 years of age, they’ll walk away. Now they can hunt on their own and they owe much to the efforts of their mother. Perhaps this is a significant part of the weaning process.
    • The strong bond between the mother and her cubs weakens as the latter grow older. If a mother intends to leave her young she just walks away from her offspring straightaway.
    • Young bear can follow the mother and track down her but soon they realize that they must start hunting instead of searching for their mother. However, sometimes the young just doesn’t listen to their mother’s warning and they prefer to stay.
    • As it turns out, the mother briskly chases the young to tell him that it must walk away. Mother and young often travels for months before they fall apart.

    Back in 80s, the polar bear population in the Hudson Bay used to leave their mother as early as 1.5 years. Studies claimed that around 55% of all cubs became independent of their mother before reaching 2 years age. That is however an exception rather than the rule. Scientists have not been to understand as to why polar bear cubs leave their mother so early.

    1. The early weaning might be due to the condition of their mothers as well as the sex of young bears.
    2. There can be another possibility which is that seals could be widespread in the early 80s—helping the young bears to grow quickly.
    3. On the Hudson Bay three different polar bear populations may have mixed. Adult males might have possibly taken the females away from their young too early.
    4. Or females may have faced food scarcity in autumn and they stopped nursing before coming to estrous again in the following year.
    5. Females may choose to have more litters in their lifetime and so they abandon their current offspring.

    Grizzly mothers usually nurse their cubs for one extra year if they feel like their yearlings are not old enough to live on their own. They do so in order to increase the likelihood of their survival. Polar bear mothers do not treat their cubs like grizzlies yet they (yearlings) manage to survive just fine. While they cannot become expert hunters they do nevertheless become scavengers to make a living. Currently, weaning before 2 years of age is probably not common. Furthermore, the sea ice in the Hudson Bay is disappearing relatively earlier forcing polar bear mothers to wean their cubs for until they reach 2.5 years of age.

    How Long Do Polar Bear Cubs Stay with their Mother? – Video

  • What Do You Call a Baby Polar Bear?

    A baby polar bear is no different from a baby brown bear, baby black bear, or a baby Kodiak bear. The baby polar bear is called a cub in pretty much the same way as lion’s baby. We often use the term cubs for most mammals’ offspring. Polar bear is just another land mammal. A baby polar bear remains a cub for the first few months since it grows quite rapidly in its initial days.

    Polar bear cubs are way too smaller in comparison to polar bear adults. In fact, they resemble the size of an adult ground squirrel. That is why the mother polar bear keeps a close eye on her cub for as long as it doesn’t reach adulthood. A baby polar bear stays for the most part of its life in a den not only to remain safe from predators—they stay warm inside the den.

  • How Much Does a Baby Polar Bear Weigh?

    Baby polar bears are way too small as compared to adult bears. They are usually born in November and February. At birth, the baby polar bear typically shows light down fur which is probably not dense enough to protect it from the chilling cold of the Arctic. Now let us see how much do polar bear cubs weigh at birth.

    How Much Does a Baby Polar Bear Weigh?

    The newborn baby polar weighs only 2 pounds or 0.9 kilogram—nearly the weight of an adult ground squirrel. It is curious that an animal weighing only a couple of pounds at birth reaches the size of the biggest land carnivore in the world. However small it is at birth, the baby polar bear grows pretty quickly especially in the initial days of its birth. The polar bear cub stays in a den for up to mid-April after which the cubs leave the den. By the time the cubs leave the den they weigh 22 to 33 pounds.

    A polar bear cub. How much does a baby polar bear weigh?. Photo by DailyMail

    Scientists wonder why do baby polar bears are born so little at birth. One probable reason (according to researchers) might be that the female polar bear doesn’t eat anything during the hibernation-like state so the baby polar bear comes out just as weak. The mother starves for months in dormancy period which indeed renders the baby polar bear rather feeble.

    How Much Does a Baby Polar Bear Weigh? – Video

    You Might Like to Read!

    • How Do Polar Bears Reproduce? – Polar bears are polygynous creatures in that their cubs may or may not belong to the same father…
    • How Do Polar Bears Communicate? – When polar bears growl it means that they are extremely angry. A deep growling may also suggest the mother bear is protecting her food..
    • How Do Polar Bears Adapt to their Environment? – Thanks to the physiological, structural, and behavioral adaptations of a polar bear that allow her not only to survive but also to live like many Arctic mammals…
    • Female Polar Bear – Female polar bear is less than half the size of a male polar bear. She is also much less in weight as compared to their mating partners…

  • What Does a Baby Polar Bear Look Like? – Baby Polar Bear Description

    While adult polar bears are perfectly insulated by the dense white fur, baby polar bears develop lighter furs in the initial days following the birth. A baby polar bear has fluffy white fur which protects the cub from extreme Arctic chill. However the cub’s fur is not thick enough to prevent them from cold if they get wet. That is to say that baby polar bear cubs likely develop hypothermia if they swim in cold water. Let us see now what do polar bears look like when they are born.

    What Does a Baby Polar Bear Look Like?

    The baby polar bear weighs only 2 pounds at birth—nearly the size of a ground squirrel. It is curious that they become the largest terrestrial carnivores from a ground squirrel. Polar bear cubs grow pretty quickly.

    A baby polar bear which is about to leave the den is relatively more fluffy and is covered with short woolly fur than the one at birth.

    A baby polar bear which is about to leave the den is relatively more fluffy and is covered with short woolly fur than the one at birth. At this age, they likely develop wavy guard hairs and tawny coat. The density of cub’s fur varies—even between the real brothers. While some baby bears show beige coat the first time they emerge from the den, others are absolutely white.

    Read More: What Do Polar Bears Look Like?

    ©MICHELLE VALBERG/National Geographic

    Unlike adults, the baby polar bears have pink skin and it remains pinkish for as long as 450 days after the birth. The skin turns black with age. Adult polar bears show absolutely black skin. Baby polar bears have tiny black eyes just like the adult’s.

    References

    Derocher, Andrew E. (2012). Polar Bears—A Complete Guide to their Biology & Behavior: 18–22.

    Kazlowski, Steven; Stirling, Ian (2010). Ice Bear: The Arctic World of Polar Bears. Seattle, WA: The Mountaineers Books.

  • Polar Bear Cub | Polar Bear Cub Description, Size, Weight, Growth

    Polar bear cubs are born blind, toothless, and virtually helpless in den. They have extremely short and light down hair at birth. Cubs lack subcutaneous fat which is what makes them vulnerable to the outside cold. As a result, the mother bear will not allow cubs to leave the material den until the right time. Couple of weeks later she will expose her cubs to the outside world.

    The critical temperature of polar bear cubs is –30◦C. The increase in oxygen consumption at 45◦C is estimated at 33%. However the overall temperature (of the cubs) remains the same. If they jump into the icy water (given the present conditions) the body temperature is going to be dropped. However the bear cubs are absolutely ready to join mother on the land but they are too weak to dive into the water.

    Polar Bear Cub – Baby Polar Bear Cubs

    Polar bear cubs weigh as little as 0.6 kilograms at birth. However they grow fast and in few days’ time cubs may become 10 – 12 kg in weight. This is the time when cubs leave maternal den but remain under the watchful eye of their mother. Polar bear cubs will continue to gain weight since the day they left den. That is to say the cubs gain weight twice as much (in the second year) as they had on their first birthday.

    Read More: Polar Bear Cubs Facts

    The cubs will suckle the fat-rich milk from their mother. Unlike other bears’, the polar bear’s milk contains the highest quantity of protein and fat. The polar bear cubs are lucky enough to receive milk even after the second birthday. This is quite unique in many other terrestrial mammals. Then again the two-year-old cub doesn’t seem to rely on milk as much. Sometimes however mothers leave suckling during the middle period after the first birthday.

    How Many Babies Can Polar Bears have?

    The reproductive biology of polar bears is nearly the same as that of other bear species. Cubs are typically born in November to February. The female gives birth to twins but three litters are also common in much of its range. In the Hudson Bay region, three newborn polar bear cubs are usually born. The captive polar bear cubs are born as early as in October.

    The polar bear cub is likely to stay inside the den from February to the mid-April. During this period the mother starves but she continues to milk her cubs. After 12 – 14 days the cubs begin to emerge with their mother. Cubs will walk, run, and play but remain close to their mother. The mother remains busy in grazing vegetation.

    Cute polar bear cub just outside its den. Polar bear cub. Photo by Mother Nature Network.

    In the Hudson Bay the female bears give birth after a relatively shorter interval which indeed makes them more prolific than the rest of the populations. In Canada, Svalbard, and Alaska, the mean litter sizes are 1.9, 1.81, and 1.61 respectively. In the Hudson Bay area, the production rates in each female is about 0.45 litters which is quite high. That is to say nearly half of females living in the Hudson Bay are reproductive each year. The rate is 0.25 in the Beaufort Sea which means that one fourth of all females are reproductive. The difference in rates clearly reflects the high productivity of polar bear population in the Hudson Bay area.

    How Long Do Polar Bear Cubs Stay with their Mother?

    • Polar bear cubs stay with their mothers for as long as 26 – 29 months. The typical weaning period lasts about two years. The mother bear is likely to go through strategic weaning in which there is a limited suckling. She will then be able to breed again. This makes the reproductive interval of 3 years in polar bears.
    • The cubs are thought to imitate mother’s hunting methods even though they are too young to hunt.

    Polar Bear Cubs Mortality

    • The mortality rate in polar bear cubs is extremely high in the first year of their birth. This is so because newborn cubs are highly vulnerable not only to the external environment but also to the potential predators. Arctic land predators are likely to prey on cubs.
    • Sometimes it so happens that the mother bears cannot feed two cubs at a time (due to starvation). As it turns out, she prefers one over the other.
    • Adult males are highly aggressive and if they find female with her cubs they might kill baby polar bear.

    Polar Bear Cub – Video