Polar bear morphology and adaptability

[oldgreengrolar]

I will add some info later.

[oldgreengrolar]

[oldgreengrolar]

"In an ideal world there would be no polar bears in zoos, for if ever there is an animal that doesn’t belong in a zoo it’s the polar bear."


www.bearconservation.org.uk/polar-bears-in-zoos

[oldgreengrolar]

The size of polar bears in captivity:
Unlike the brown bear, polar bears in captivity are rarely overweight or particularly large, possibly as a reaction to the warm conditions of most zoos.
www.projectnoah.org/spottings/11801217

Captive polar bears.


In an ideal world there would be no polar bears in zoos, for if ever there is an animal that doesn’t belong in a zoo it’s the polar bear.

These Arctic giants have huge ranges in the wild, traveling many of hundreds of miles in their search for food. They have evolved over millennia to exist and thrive in the harsh environment of the Arctic. It is our belief, based on considered scientific evidence, that polar bears are a species that should never be bred in captivity, nor should they be actively sourced for captivity from the wild. However, even if this ideal state were to be achieved, there would still be problems and issues around what to do with cubs found orphaned in the wild and “problem bears” captured in populated areas.

Sadly, most captive polar bears are kept in facilities, and often in climates, which are totally unsuitable. Only a very few facilities provide sufficient space for the bears to live anything approaching a contended and fulfilling life. So it is not surprising that many captive polar bears manifest symptoms of extreme stress, such as continually shaking their heads, pacing up and down their enclosures or swimming in a stereotypical fashion.

Captive polar bears, along with orcas and other cetaceans, suffer from more sickness and psychologically related illness than any other animals kept in captivity.

We are compiling a comprehensive directory of all the polar bears currently kept in captivity and of the facilities where they are kept. If you would like to help with this work then please get in touch.

We have three main goals:

An end to all captive polar bear breeding programmes. Many of the cubs born in captivity die within a few years, or even months, of birth. Breeding polar bears in captivity can never “save the bears” from extinction, nor repopulate the wild. No captive-born polar bear has ever been successfully released into the wild; indeed to do so would be contrary to IUCN regulations.
The upgrading and improvement of substandard facilities holding captive polar bears to provide modern, state of the art “off exhibit” and “on exhibit” areas that meet the highest possible standards for housing, enrichment, general welfare and veterinary services. Air conditioning, water features and a total area of at least 8,000 square metres (2 acres) per animal are, we believe, the minimum essential for high welfare standards to be maintained.
Where the above cannot be achieved facilities must be closed, with the polar bears transferred to modern, high standard facilities in sanctuaries or zoos.

www.bearconservation.org.uk/polar-bears-in-zoos/

[oldgreengrolar]

Polar Bear Fur Is Completely See Through.

You may not believe it but Polar bear fur is actually completely see-through, though this doesn’t mean they will be green if they stand on a green lawn. They will appear white because of the way light scatters when reflecting off their transparent fur. Okay we lied, they do sometimes look green! But only because when it gets really too hot, polar bears have been known to stick green algae on themselves to keep cool.



Ask anyone what color a polar bear is and they will probably quickly reply that they are white. However, the truth is that their fur is transparent and has no color at all. They appear to be white to the naked eye because their fur reflects the visible light.



Due to their transparent fur, if you were to try to take a photo of a polar bear in infrared light then they would barely show up at all. Though perhaps the most surprising thing is that their skin color is actually black. To creatures and humans that can only see visible light, polar bears are the perfect predator that is able to blend in almost perfectly into their environment.



However, one mammal has evolved to deal with this situation: deer have a visual system that can outsmart the polar bear’s tricky fur. Deer can actually see in ultraviolet light which allows them to see polar bears extremely easily when they appear on top of an icy white backdrop.



When you see a polar bear at the zoo you may be mistaken for thinking they are yellow or green, but this is due to dirt and age. Or unfortunately, in humid and hot temperatures where polar bears are not native, they sometimes start to see algae growing on their skin. And it can also depend on their diet, for example, when they eat a lot of seals then their fur can start to turn yellow due to the seal’s oil.

insidetonight.com/polar-bear-fur-is-completely-see-through/

[oldgreengrolar]

Do polar bears have strong teeth?

They are designed to allow the Polar Bear a way to easily dig and to scoop the ice. Polar Bears have a mouth full of 42 extremely sharp teeth. Since they are carnivorous, they need them to kill their prey as well as to consume it. Their teeth are longer and sharper than those of the Brown Bear.





www.polarbear-world.com/polar-bear-anatomy/

[oldgreengrolar]

Body Type.

Polar bears have a heavy stout body with strong muscular legs and well-developed neck muscles. Compared to other bears, the head of a polar bear is proportionally smaller. The necks of polar bears are longer than their nearest kin, the brown bear. This adaptation makes it easier for them to keep their heads above water when swimming. They have short, fur covered ears and a very short tail. Polar bears have large paws compared to body size, reaching 30 cm (12 in.) in diameter. The large paws of a polar bear act like snowshoes, spreading out the bear's weight as it moves over ice and snow. The forepaws are round, and the hind paws are elongated. The partial webbing between their toes, polar bears are able to use their front feet much like paddles to propel them rapidly through the water. The hind feet are slightly smaller. On both the front and hind feet, the bottoms are covered with dense fur, which affords better traction when moving on ice. Each toe has a thick, curved, nonretractable claw. The claws are used for grasping prey and for traction when running or climbing on ice. The sole of a polar bear's foot has thick, black pads covered with small, soft papillae (dermal bumps). The papillae create friction between the foot and ice to prevent slippage. Long hairs growing between pads and toes also help prevent slippage. Polar bears walk in a plantigrade manner (i.e., in a manner similar to humans with both heel and toe make contact with the ground when walking). On land, they are not as quick as brown bears and appear to have traded off speed for their extremely massive forelegs which they use to break through seal dens or flip a large seal out of the water. They are able to attain speeds of 40 kilometers per hour (25 miles per hour) for short distances.


myweb.facstaff.wwu.edu/~brilla/PBear.htm

[oldgreengrolar]

Hibernation







Hibernating means to pass the winter in a dormant or lethargic state. Animals that hibernate store body fat when food is plentiful. When food is scarce, they hibernate, living off their stored body fat. Polar bears do not enter deep hibernation. Deep hibernation applies to an animal whose body temperature drops to 5C (41F) for a period of days or weeks. Deep hibernators also show a marked drop in heart rate, and are slow to wake up when disturbed. Only pregnant female polar bears hibernate. Polar bears are not deep hibernators, but enter a state of carnivore lethargy. Though hibernating females sleep soundly, they are easily and quickly aroused. The female polar bear's heart rate slows to about (8-12 bpm at a low) 27 beats per minute from a normal resting heart rate of about 46 beats per minute.When hibernating, a female's body temperature may drop slightly, perhaps to 35C (95F), or it may remain normal at 37C (98.6F). Unlike many other animals who hibernate, its body temperature only undergoes a minor reduction of 3 to 7 degrees Centigrade (5 to 9 degrees Fahrenheit). Its metabolism slows down by half. Unlike most other hibernators, female polar bears give birth while hibernating. High body temperature is needed to meet the demands of pregnancy, birth, and nursing. Researchers have found that nonhibernating polar bears, during times of food scarcity, can efficiently utilize their energy reserves much like hibernating bears. During the period of hibernation, the polar bear will neither pass urea or solid fecal waste. While urea poisoning causing death would occur in all other animals within a week, bears have developed a unique process of recycling the urea into usable proteins. During the hibernation period, all bears lose a great deal of weight. It is not uncommon for a female polar bear with newborn cubs to lose as much as 40% of her weight.





myweb.facstaff.wwu.edu/~brilla/PBear.htm



Judging from the sentence underline, it shows that polar bears with 50% fat are pregnant females.

[oldgreengrolar]

[oldgreengrolar]

Appearance:

Polar bears are extremely well-adapted to their arctic environment. They have the thickest fur of any bear species. It’s composed of two layers. The layer closer to the body, the undercoat, consists of thick, plush hair that retains heat. The outer layer provides extra insulation and repels cold water and ice. This layer of “guard hairs” is not hair at all but is rather composed of clear, hollow tubes. The tubes trap air for insulation and also reflect all the visible wavelengths of light in their hollow airspace, which combine to make the fur look white, though it is in fact colorless. The white coloring provides excellent camouflage for the bears, allowing them to blend in with their snowy surroundings.



Polar bears molt in the summer months and grow a new coat. By the next spring, the coat may look yellowish from seal oil stains. They sometimes wash their fur in ice or snow during or after feeding.



Underneath their fur, polar bears have black skin which absorbs the heat of the sun, and below the skin is a thick, 4-inch layer of blubber. This blubber layer is particularly beneficial while polar bears swim, keeping them warm in the cold water and increasing buoyancy.



Polar bears also have fur on the bottoms of their paws, providing extra warmth and creating traction on the ice. The bottoms of their paws are also covered with small bumps called papillae. The paws are broad to distribute their weight as they walk across ice and snow, and tipped with long, powerful claws to help grip the ice.



Compared to other bears, the polar bear has an elongated body with a particularly long neck and a narrow skull. These features streamline the bear, making it an efficient swimmer. Large, flat, and partially webbed paws, functioning like oars, also help them navigate the water.


www.pbs.org/wnet/nature/blog/polar-bear-fact-sheet/

[oldgreengrolar]

First 'tropical' polar bear put down after five-year health battle




www.google.com/amp/s/www.independent.co.uk/news/world/asia/singapore-polar-bear-inuka-dead-health-arthritis-dental-problems-ear-infections-latest-a8321121.html%3famp

Old news but it shows polar bears become sick outside their natural environment. The warmer it gets, the sicker they generally become .

[oldgreengrolar]

www.eatsleepswimcoach.com/muscles-during-freestyle/

Swimming does involve using the muscles no other forms of exercise does. Weight lifting might get one bulkier but it does not exercise the whole body.

Kodiak bears have strong forearms due to digging and possibly flipping rocks but polar bears which swim more often might exercise certain muscles more.

[oldgreengrolar]

Animal Super Parents

www.bbc.co.uk/programmes/articles/2RQsPdD6zXjS02zgwksR4Yp/polar-bears

Polar bears

Polar bears mate on the sea ice in April or May, and cubs are born between late December and early January.

The pregnant female survives the 7-8 months or fasting by using stored body fat – they may lose up to 40% of their body mass during this time.

Newborn polar bears have no fat layer and short fur when they are born, so can’t emerge from the den until they can cope with the cold.

By the time a cub leaves the den, it has grown to 10 kg in weight. It has thicker fur than a newborn, but still has very little subcutaneous fat.

Small cubs survive the cold by having a high metabolic rate, fuelled by the fat content of mum’s milk.

Polar bear milk is 31 to 35% fat. (Cow milk is 4% fat).

Most cubs are nursed until they are two years old, though some are weaned after their first year. They are dependent on their mothers for their first two years – during this time they learn survival skills and hunting techniques.

Polar bears can weigh 50% more at the end of the good season (seal hunting) than they do at the end of summer (lean times – seals out at sea).

Polar bears put on most of their fat reserves between late April and mid-July.

An average polar bear can consume 4.4 pounds of fat a day (2 kg of fat a day).

Why not eat the meat?

Fat is more energy rich that protein. So they eat the blubber, not the meat. To break down and digest large amounts of protein, you need to get rid of the excess nitrogen in the protein by peeing it out in your urine. However, to produce lots of urine, you have to drink lots of water.

There is no drinking water on the polar ice cap! To get drinking water the polar bears would have to eat snow, or eat specific bits of icebergs (sea ice and sea water are too salty and would make them thirstier than they started out). Eating snow or ice would lower the polar bear’s body temperature, which is not a good idea. For comparison, Inuit/Eskimo peoples’ traditional diet of seal and whale meat meant that they had to drink a lot of water. They got it by melting ice and snow in pots fuelled by seal oil.

So eating too much meat in a cold climate is a bad idea for a bear – stick to the fat.

[oldgreengrolar]

Do polar bears have strong teeth?

They are designed to allow the Polar Bear a way to easily dig and to scoop the ice. Polar Bears have a mouth full of 42 extremely sharp teeth. Since they are carnivorous, they need them to kill their prey as well as to consume it. Their teeth are longer and sharper than those of the Brown Bear.


www.polarbear-world.com/polar-bear-anatomy/

[Bolushi]

Feb 19, 2023 9:38:00 GMT oldgreengrolar said:

I've seen some polar bears live in zoos before in the USA even in southern areas (online) and they were OK?