Polar Bear Nutrition: Considerations for Wild and Captive Bears
Polar bears are viewed as the black sheep of the bear family; their semiaquatic lifestyle sets them apart from all other bear species. Unlike the seven other species of bear, polar bears are classified as marine mammals (Dierauf & Gulland, 2001). The unique way they balance their life between the land and sea means that their dietary requirements and the food that is available to them is highly specialized to their environment. Polar bears that live in captivity have similar nutritional requirements to their wild counterparts, but the way they receive those nutrients is very different. It is important to understand that the nutritional requirements of polar bears, both in the
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In the wild, they prey primarily on the ringed seal but polar bears will also consume whales, walrus, reindeer, sea birds, and vegetation (Lintzenich et al., 2006). Their dietary intake is seasonally dependent. AZA Bear TAG (2009) explains that polar bears use the sea ice as their hunting grounds and when that ice melts, polar bears can be restricted to land for up to 6 months. During this time they may be forced to fast or have very limited food intake. Their survival during this time is dependent on the fat stores they were able to build prior to the warmer season (Dyck & Morrin, 2011). Polar bears live a very active lifestyle so the consumption of high energy food is important. The most important nutrients that need to be included in their diet are protein, fat, carbohydrates (plant material), vitamins (Vitamin A, Vitamin B, etc.), minerals (Iron, Zinc, Copper, etc.), and water (Lintzenich et al., …show more content…
As stated by AZA Bear TAG (2009), polar bears in these life stages have higher protein requirements. Typically, polar bears will only consume the skin and blubber of a seal; in order to increase their protein consumption, they will consume the entire seal carcass (Dierauf & Gulland, 2001). Once a female has been mated, she will increase her food consumption and begin storing at least 200 extra pounds of fat before giving birth (Dierauf & Gulland, 2001). Polar bear cubs consume their mother’s milk, which is high in fat content, for 18 to 30 months; as they get older, they will also eat the seal carcass after the mother has removed the blubber (AZA Bear TAG,
Williams, C. T., Goropashnaya, A. V., Buck, C. L., Fedorov, V. B., Kohl, F., Lee, T. N., and Barnes, B. M. (2011). Hibernating above the permafrost: effects of ambient temperature and season on expression of metabolic genes in liver and brown adipose tissue of arctic ground squirrels. J Experi Biol. 214, 1300-1306.
The Arctic region is home to a variety of valuable animals and plants, including polar bear, seal, and so on. The ecosystem of the Arctic region is fragile because these animals are evolved to live in extreme conditions. With the climate change, many animals are endangered. Ice is the habitat of polar animals because they have to rely on sea ices for resting, food, and reproduction. With the climate change and the decrease of sea ice, the number of polar animals is decreasing and their health is threatened. For example, the average weight of female polar bears in 1980 was about 650 pounds, but the number reduced to about 500 pounds in 2004 (Djoghlaf 15). The earlier breakup and later condensation of sea ice shortens the hunting season of polar bears. Polar bears mainly feed on seals that indwell icy land. The melting ice reduces the number of seals and food intake of polar bears. In addition, polar bears are used to living in ice caves. The rising temperature causes the collapse of ice caves, which can kill baby bears. The climate change is negatively affecting the biodiversity in the region and will definitely harm the ecosystem
grizzlies will hibernate when there is a seasonal shortage of food, low environmental temperatures, or when there’s snow arrival. Grizzly bears hibernate five to seven months each year. The grizzly will enter into hibernation in October or November. During this time the grizzly bear must prepare a den and consume as much food as possible to last their hibernation period. While searching for a den the grizzly may travel many miles until it finds a suitable area that it likes. The dens are usually at elevations above 1,800 m (5,900 ft) on north-facing slopes. The reason why bears have to eat as much food as possible is because they need the energy from the food to last through the entire winter. They may eat up to 90 lbs of food per day, while trying to put on as much weight as possible. When it’s time for grizzlies to hibernate; will enter their den, and fall into a “deep” sleep. During this time the grizzlies won’t eat or drink; but instead they digest their stored up fat; (the fat used to last them through their entire hibernation.) The bear also will not urinate or defecate, but will reabsorb their urine and feces into proteins. The bear can use 25-40% of their body weight during hibernation; the bear’s heart rate and body temperature may also drop. By March or April, male grizzly bears usually emerge from the den and the females emerge in late April or May. When bears emerge from hibernation they’re
The tundra is located at the top of the world near the North Pole. This huge habitat covers one fifth of the earth's surface.
they are at the top of the food chain of the grassland plants and animals. Grizzly bears are powerful, top-of-the-food-chain predators, yet much of their diet consists of nuts, berries, fruit, leaves, and roots. Bears also
As summer approaches, blue whales migrate to feeding grounds near the north or south poles. Concentrations of krill are greatest in these areas during the summer, and it is then that the whales eat huge amounts of food. Groups of blue whales can be seen at this time, especially around Antarctica. In the fall, after feeding for half a year, the whales begin to swim toward warmer water to mate and to give birth to their young in the warmer, calmer water. Females give birth to one calf every two or three years. Newborn calves are about 23 ft long and weigh almost 6000 lbs. The hungry babies may drink more than 50 gal of rich milk from their mothers daily, and grow very quickly, gaining up to 200 lbs a day.
The diet of a Greenland will eat almost anything that it will come across. With its
Out of an Ice Age emerged one of our most majestic creatures in the world the polar bear. From its brown bear ancestry, the predator evolved to be a master of a harsh and unwelcoming ice kingdom. Intelligent, adaptable and fierce, the polar bear learned how to survive in a place that offers few comforts to any creature. But now that very environment is in flux. And so is the polar bear’s fate (Nature). Polar Bears are very different from other bears. Polar bears are very large bears compared to Black bears. Polar bears weigh anywhere between 330-1700lbs and Black bears weigh anywhere between 150-600lbs. They have strong legs with large, flattened feet with some webbing between their toes that help with walking on ice and swimming. The wide paws prevent sea ice from breaking by distributing weight while walking. Their paws allow them to pull a 600 pound seal out of its breathing hole (Rosing, 20). The webbed feet results in making polar bears, unlike other bear species to be considered as marine mammals along with seals, sea lions, walruses, whales and dolphins (Polar Bear). According to Rosing Polar bears are excellent swimmers and have been known to swim up to six miles an hour and as far as 60 miles at a stretch. The bears paddle with their front feet and steer with their back feet. They often overheat. Sometimes they venture into the waters just to cool off. When a bear climbs on an ice floe, it shakes itself off because it is trying to prevent ice from forming on its fur (22-23). Because of climate change and hunting of polar bears are now becoming an endangered species which is affecting the food chain. We can fix this by going green, banning polar bear hunting and keep creating these new hybrid bears that are mixed with griz...
animals such as the polar bear, to mate and to prepare for the once again
In recent decades, the global warming threat has captured the attention of the nation and the world. While the main focus began with concentrating on the effects this long-term natural crisis would have on the human population, select groups have worked to approach the topic in a manner that entails prevention in order to help other animal and plant species around the globe. One such organization is the National Oceanic and Atmospheric Administration, which has played a major role in the conservation of the polar bear species, one of the mammals most adversely affected by the recent climate changes. As more research has been conducted regarding the polar bears, scientific name Ursus Maritimus, the conclusions have been shocking. In 2008, the Department to the Interior listed the polar bear species as “threatened” under the Endangered Species Act of 1973 awarding it some protections mandated by the federal government (Wolfe). However, on January 5, 2011, Representative Donald Young proposed a bill in Congress in order to delist the polar bears as threatened, thus decreasing and even removing the conservation efforts that have been set in place over the past three years. The polar bear Species should remain listed under the Endangered Species Act because ice thickness has decreased 40 percent during the past 30 years thus reducing the polar bears’ critical environment, if current conditions continue the polar bear populations around the world may decrease by two thirds by mid century, and since the species has been protected under the Endangered Species Act the worldwide populations have experienced stabilization or growth in most circumstances.
“Killer whales are the largest of the dolphins and one of the world's most powerful predators” (Killer). It does not take much thought and research to know a killer whale’s diet do not consist of buckets of frozen fish. Killer whales “feast on marine mammals such as seals, sea lions, and even whales…” (Killer) The question now is how do the killer whales in captivity even live with the unfulfilling diet they are put on? After reading about a killer whale’s diet, I came across horrifying research an author wrote about, it includes SeaWorld adding supplements to killer whales’ diets in order to keep the whales alive and healthy. The text I found includes “…supplements are even added to
In an article titled “Energy Digestibility of Giant Pandas on Bamboo-Only and on Supplemented Diets”, the goal of this study was to figure out the energy digestibility of bamboo by giant pandas using digestibility trials and through analysis using bomb calorimetry. An energy budget is a numerical statement that measures the amount of energy collected and the placement of the energy to various functions. Energy budgets can be described using the equation: E=M+P+U+F (where E is the total amount of energy consumed, M is the energy used for maintenance and activity, P is the energy used for production (which includes growth and reproduction), U is the energy lost in urine, and F is the energy lost in feces.). The total energy consumed minus the energy lost in feces is the digestible energy and shows the ability of the digestive system to process consumed food.
To begin with, the melting of polar ice caps has caused polar bears to swim long distances. According to Bryan Walsh of TIME Magazine the melting of the ice caps have caused polar bears especially the young cubs to swim longer distances which has caused a “ forty-five percent mortality rate” (Walsh). In the article Walsh, writes about a study that showed that younger cubs because of low fat and strength were more likely to die due to the long di...
Polar bears don't just live on ice, they use the ice as an advantage to catch prey such as seals. Polar bears have adapted to living on ice and being able to withstand the cold weather. Now that the climate is changing at a fast pace, polar bears are losing their land because its melting, leaving them with no place to walk, sleep and taking away their way of hunting prey. (polar bears international, 2015) This is all happening so fast that there is no way polar bears will be able to adapt to the new environments, causing extinction. The arctic is warming twice as fast as the rest of the world is due to the build up of greenhouse gases in the atmosphere, making it a problem happening very rapidly. (Bagley, 2015) Temperatures in the Arctic region have risen 7 degrees Fahrenheit over the last half century. (Bagley, 2015) Population among polar bears has decreased up to 40% in some areas. (Bagley, 2015) With the climate getting warmer, ice is melting earlier every spring, and takes longer to freeze every winter which is disrupting the feeding and breeding cycles of many different arctic species. (Bagley, 2015) Polar bears have adapted ways to survive in the cold harsh arctic environment including having the ability to cool down their outer skin to keep their vital organs warm when they are submerged in cold water. Though this may help the delay of hypothermia as they have to swim greater distances from ice shelf to ice shelf, that doesn't mean polar bears can swim forever. (Bagley, 2015) One bear that a scientist studied swam 500 miles over nine days, but lost 22% of her body weight, and lost her cub.(Bagley, 2015) Many different scientists have been studying the behaviour of the polar bear to see if it could adapt in any way to survive. Eight U.S scientists made a hypothesis consisting that polar bears could lower their metabolic rates enough to survive as food
White Bear, an episode of the TV series “Black Mirror”, can be seen as a critique of today’s criminal justice system. The eye-for-an-eye mentality seen in the show prevents society from improving after a tragic crime and concurs with the concept of capital punishment. Criminals should be rehabilitated in attempt to make them better citizens as opposed to suffering at cost of retributive justice. Sentencing offenders to retribution is very counterintuitive and does more harm than good and the episode “White Bear” can be seen as evidence of this concept. In addition, it is not doing Victoria, the main character, any good having the public ridicule her. The customers of White Bear are so bored with their own lives they find joy in watching others