Bears do not eat, drink, urinate, or defecate while in the den. Fat is metabolized to produce water and food, but instead of defecating or urinating to eliminate waste, bears recycle it. Their kidneys shut down almost completely and urea, a major component of urine, is recycled into proteins that maintain a bear’s muscle mass and organ tissues.
How do Bears get rid of waste?
Waste products are produced, however, instead of disposing of their metabolic waste, bears recycle it. The urea produced from fat metabolism (fatal at high levels) is broken down and the resulting nitrogen is used by the bear to build protein, which allows them to maintain muscle mass and organ tissues (Rogers 1981).
What happens to urea in hibernating bears?
Urea is degraded, again by an unknown mechanism: one theory is that urease-producing bacteria in the gut aid in breakdown. Nitrogen is also thought to be shunted toward protein anabolism. The amazing result is that blood from hibernating bears does not contain an elevated level of urea, uric acid, amino acids, or ammonia.
How does urine get reabsorbed through the bladder?
A small amount of urine, about 100 mL, is produced, and the water and nitrogenous breakdown products are reabsorbed through the bladder. How does this happen? No idea. Urea is degraded, again by an unknown mechanism: one theory is that urease-producing bacteria in the gut aid in breakdown.
Can urine be recycled into fertilizer?
The Gotland project is part of a wave of similar efforts worldwide to separate urine from the rest of sewage and to recycle it into products such as fertilizer. That practice, known as urine diversion, is being studied by groups in the United States, Australia, Switzerland, Ethiopia and South Africa, among other places.
How do bears survive in the winter?
When do bears hibernate?
What is the normal temperature of a bear?
Do bears sleep in the winter?
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How do bears turn urine into protein?
Instead, bears are able to literally turn their pee into protein through a urea recycling process. The urea produced by their fat metabolism is broken down and the nitrogen is re-used by the bear to rebuild protein.
How do bears excrete waste?
"Bears don't eat, drink, urinate or defecate for six or seven months," he says. They make their own water, probably by metabolizing fat, and they get rid of wastes by breaking them down internally.
How do bears recycle waste during hibernation?
Grizzly bears and black bears generally do not eat, drink, defecate, or urinate during hibernation. Bears live off of a layer of fat built up during the summer and fall months prior to hibernation. Waste products are produced, however, instead of disposing of their metabolic waste, bears recycle it.
How do bears get rid of fecal plug?
Bears have been observed licking and chewing on their own footpads during the later months of hibernation, and bits of this dried callused skin has been found in fecal plug material. Fecal plugs are expelled by the bear upon waking in spring, usually near the entrance to the den.
When animals hibernate do they poop and pee?
Even those hibernators that don't eat or drink anything at all sometimes defecate and urinate during hibernation (metabolizing stores of fat does produce waste), but these animals expel only a tiny amount during hibernation. Hibernating bears, on the other hand, can go the whole winter without going to the bathroom.
How do bears not drink during hibernation?
Hibernating bears enter a shallow torpor with a decrease in body temperature of only 10 degrees. It's metabolism and hear rate slows down. But it doesn't need to eat, drink or pass waste. In order to survive, fat in the bear's body breaks down into water and calories for the body to use.
Do bears have to pee when they hibernate?
Hibernation for bears simply means they don't need to eat or drink, and rarely urinate or defecate (or not at all). There is strong evolutionary pressure for bears to stay in their dens during winter, if there is little or no food available.
How do bears recycle urea?
Fat is metabolized to produce water and food, but instead of defecating or urinating to eliminate waste, bears recycle it. Their kidneys shut down almost completely and urea, a major component of urine, is recycled into proteins that maintain a bear's muscle mass and organ tissues.
Why can't humans hibernate?
Firstly, our evolutionary ancestors were tropical animals with no history of hibernating: humans have only migrated into temperate and sub-arctic latitudes in the last hundred thousand years or so. That's not quite long enough to evolve all the metabolic adaptations we would need to be able to hibernate.
Why do bears poop on the road?
Bears leave scat on trails, in feeding areas, near where they're bedding, but they also defecate when they're stressed or scared. Bears often relieve themselves when unexpectedly spooked or right after they've been shot. Sometimes bears leave scat when they're walking up a hill and their body is stressed.
How big is bear poop after hibernation?
1½ to 2½ inchesDuring 5-7 months in dens, bears accumulate feces in the lower 7-15 inches of the intestine to form a “plug” 1½ to 2½ inches in diameter. The fecal plug is simply feces that have remained in the intestine so long that the intestinal walls have absorbed the fluids out of it, leaving it dry and hard.
Do bears clog their butt?
Bears usually don't eat, drink, urinate or defecate while hibernating. They produce a faecal plug in their colon, a dry and hard mass consisting of dead intestinal cells, hair and bits of plant-based bedding materials. When the bears wake up in spring, they eject the faecal plug just outside their den.
How does bear country deal with garbage?
Always place trash in bear-resistant dumpsters in campgrounds or in bear-resistant containers at campsites (storage lockers/bear boxes), and close and lock after each use. Never leave scented items unattended in campsites, tents, or vehicles.
Do bear dumps still exist?
Visitors were getting too close to the bears and getting injured, and the park realized it had to make some changes. It ended all bear feeding shows in the 1940s and closed the dumps in 1970.
What is a bear dump?
Bear dumps once made that pretty easy. Now, you have to smother your wife and daughter in a combination of peanut butter and marshmallows and leave them in the woods overnight while one observes from a safe distance away.
How do bears sweat?
Bears, like dogs, do not have sweat glands. Because of this, they must cool themselves through other means: Balancing energy expenditure and food intake.
What happens to a bear's renal function when it goes into hibernation?
The details behind what does happen to renal function and nitrogenous waste disposal in hibernating bears is unfortunately not fully worked out yet, but what is known is a fascinating example of adaptive physiology.
How long do bears hibernate?
Bears hibernate in spans of a few weeks to several months, depending on the species, the weather, and available food stores. During that period, their metabolism drops to about a third of normal. There is a shift away from protein and carbohydrate metabolism toward fat breakdown.
Do bears have nitrogen?
Nitrogen is also thought to be shunted toward protein anabolism. The amazing result is that blood from hibernating bears does not contain an elevated level of urea, uric acid, amino acids, or ammonia. They replenish the water lost via respiration via lipolysis, where water is an end product.
Do bears go into ketosis?
They replenish the water lost via respiration via lipolysis, where water is an end product. Interestingly, despite increased fat metabolism, bears do not develop a ketosis. Again, not sure why (may be related to increased glycerol metabolism).
Do bears have renal function?
The simple answer to the headline question is: no, they do not. The details behind what does happen to renal function and nitrogenous waste disposal in hibernating bears is unfortunately not fully worked out yet, but what is known is a fascinating example of adaptive physiology.
Why can't bears hibernate?
They experience metabolic suppression and some data suggests that adult-sized bears can reduce their metabolic rate some 75% below normal. So while other hibernators drop their body temperatures way down (and bears don’t), bears still can do some pretty remarkable things with their body to survive the winter. Not to mention bears can recycle their urine.
Why do bears wake up at 9 a.m.?
It takes them a long time to get their bearings … speaking of bearings, bears can wake up in an instant, because they’re not in as deep a recessive state as hibernators, thus you shouldn’t go poking around bears in the winter.
Why do bears use nitrogen?
The urea produced from fat metabolism (fatal at high levels) is broken down and the resulting nitrogen is used by the bear to build protein, which allows them to maintain muscle mass and organ tissues (Rogers 1981). Bears lose fat and may actually increase lean-body mass while hibernating due to this nitrogen recycling (Wickelgren 1988).
What do bears cover their den with?
After completion of a den (which consists of an entrance, a short tunnel, and a chamber) bears will cover the chamber floor with bedding material ranging from spruce boughs to duff.
What is the hibernation of bears?
Hibernation is an adaptation to a seasonal shortage of food, low environmental temperatures, and snow cover on the ground (Craighead and Craighead 1972; Tietje and Ruff 1980). Bears hibernate during the winter months in most areas of the world. Duration of winter denning is dependent upon latitude and varies from a few days or weeks ...
When do bears go into dens?
Movement to dens is correlated to weather and snow conditions with most movement usually occurring from late October to mid November (Judd et al. 1986). However, Craighead and Craighead (1972) found hibernation onset varied by as much as one month depending on weather conditions. Latitude also influences den entrance, with bears in northern latitudes denning earlier and longer than bears in southern latitudes (Haroldson et al. 2002). Bears will remain in the area of their den for a few weeks and enter a state of lethargy during which they eat nothing and sleep frequently (Craighead and Craighead 1972). According to Craighead and Craighead (1972) and Servheen and Klaver (1983), final den entry occurs during severe snowstorms. In theory the fresh snow will hide any tracks or other evidence of where the bear's den is located. Pregnant females usually enter dens first, followed by females with young, subadults, and lastly, adult males (Haroldson et al. 2002, Linnell et al. 200). Grizzly and black bears breed from May through July but embryonic implantation does not occur until around December, about one month after solitary females den. The cubs are born in late January or early February and are naked, blind, and helpless (Rogers 1981). They measure only about 8 inches (20 cm) long and weigh from 8 - 12 ounces (224 - 336 g). The newborn cubs do not hibernate. They sleep next to their mother, nurse, and grow rapidly. When black bear cubs emerge from the den at about three months of age, they weigh about 4 - 8 pounds (1.8 - 3.6 kg) and are able to follow their mother around in search of food (Rogers 1981). At ten weeks of age, grizzly bear cubs weigh 10 - 20 pounds (4.5 - 9.0 kg) (Brown 1993).
Where do grizzly bears dig?
In the Yellowstone ecosystem, grizzly bears tend to dig or locate dens on the mid to upper one-third of 30°-60° slopes with northern exposures between 6,562-10,006 ft, =8103 ft (2,000-3,050 meters, =2,470 m) in elevation (Judd et al. 1986). Pregnant females den at higher elevations than other females and male bears (Haroldson et al 2002). Black bears locate or excavate dens on 20°-40° slopes (=27.8°) with northerly aspects between 5,800-8,599 ft, =7,346 ft (1,768-2,621 meters, =2,239 m) in elevation (Mack 1990).There are several different types of dens utilized by bears. Black bears tend to excavate dens, den under windfalls, in hollow trees or caves, and in previously occupied dens (Jonkel 1980). Grizzly bears tend to excavate dens at the base of large trees often on densely vegetated north-facing slopes. This is advantageous in the Yellowstone ecosystem due to prevailing SW winds which accumulate snow on northerly slopes and insulate dens from temperatures which often drop as low as -40°F to -60°F (-40°C - -51°C) (Craighead and Craighead 1972; Jonkel 1980; Vroom et al. 1980). Grizzly bears in YNP usually dig new dens but on occasion, dens (especially natural cavities) are re-utilized (Craighead and Craighead 1972; Judd et al. 1986; Miller 1990). Most dens are dug in sandy loam soils with some occurring in clay loam and rocky silt soils (Judd et al. 1986). Reuse of excavated dens is rare but does occasionally occur. Usually excavated dens collapse the spring after they are dug due to runoff and are unusable. Some grizzly bears excavate dens long before the onset of hibernation while other bears tend to wait to almost the last minute to construct dens (Craighead and Craighead 1972). Major den excavation is completed in 3-7 days during which a bear may move up to a ton of material (Brown 1993; Craighead and Craighead 1972). After completion of a den (which consists of an entrance, a short tunnel, and a chamber) bears will cover the chamber floor with bedding material ranging from spruce boughs to duff. The bedding material has many air pockets which trap body heat and form a microclimate around the bear helping to keep it warm (Craighead and Craighead 1972). These bedding materials are related to availability at the den site and not on the bears preference (Judd et al. 1986). The den entrance is usually just large enough for the bear to squeeze through. This minimal opening size helps prevent heat loss during hibernation since a smaller opening will be covered with snow more quickly than a large opening. In some dens the tunnel is dug straight into a hillside or at a slightly upward angle, an energy efficient design that reduces heat loss from the den chamber. However, some dens are not energy efficient and have tunnels dug at a downward angle which allows heat to escape through the den entrance. In most dens, the chamber is dug only slightly larger than the bear allowing for efficient heat retention. However in some natural cavities used as dens, the chamber is much larger than the bear. Males and females with young usually dig the largest dens.
How hot do bears have to be to be hibernating?
This allows bears to react to danger quicker than hibernators whose body temperature may be less than 40° F (4° C) and who have to warm up before they can move quickly (Bagget 1984). Many scientists now consider bears to be super hibernators.
How does a den tunnel work?
In some dens the tunnel is dug straight into a hillside or at a slightly upward angle, an energy efficient design that reduces heat loss from the den chamber. However, some dens are not energy efficient and have tunnels dug at a downward angle which allows heat to escape through the den entrance.
Social and Environmental Benefits of Urine Recycling
One man’s trash is another man’s treasure. The same could be applied to urine since it’s our body’s waste liquid product, but thanks to its chemical composition, it can be a real treasure (if you’re a plant).
Urine as fertilizer
We as humans are not very proficient in dealing with the waste our bodies produce. All around the globe, the wastewater is left to enter the earth’s waterways, creating health and environmental problems.
Water Filter Systems and the Pee-Pee
The idea behind composting toilets is rationalizing the use of drinking water – which is why they don’t use the flush system. Bearing in mind that your urine has to be diluted (1:10) with water, greywater comes in handy as it’s perfectly suited to be a diluent.
Reed Bed
A reed bed’s purpose is to mimic a wetland, which simulates a natural filtration system for Grey wastewater treatment, including the urine.
Banana Circle
One of the most potent designs of tropical permaculture is the banana circle, also known as a pit garden. This is just a term, though. Note that it doesn’t necessarily need to include bananas if the climate conditions aren’t favorable (although, there are some banana plants that can withstand low temperatures).
Fast Solution
Since urine is low in pH and ash has a higher pH level, the mix of the two creates a pH-neutral substance. Using just the handful of sifted wood ashes (the chunks can be saved for the compost bin) will boost the potassium level in a bucket of liquid gold very nicely. Also, wood ashes have an N-P-K ratio of about 0:1:3, plus a lot of calcium.
Urine Recycling: Why Do We Do It?
Rethinking what our bodies naturally produce is crucial for us moving forward with sustainability and eco-conscious living. So the next time you pee in one of our separators, think of all the plants that will enjoy all the NPK you don’t need anymore!
Mixed waste
Urine used to be a valuable commodity. In the past, some societies used it for fertilizing crops, tanning leather, washing clothes and producing gunpowder.
Uses for urine
Separating urine is just the first step in transforming sanitation. The next part is working out what to do with it. In rural areas, people could store it in vats to kill any pathogens and then apply it to fields. The World Health Organization provides guidelines for this practice.
Mini-DNA strands knock macroscale blocks into shape
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How many times does a grizzly bear's heart beat?
Structural Changes in Heart Disease During hibernation, a grizzly bear's heart beats at about 18 beats per minute--one fifth the rate it pumps during the rest of the year. A typical human heart beats between 60 and 80 times per minute, and would never get that low, but if it did slow significantly, the atria (upper heart chambers) would distend with the backflow of blood that was not properly circulating... Courtesy Lynne Nelson
Do polar bears hibernate?
Obesity and Diabetes Polar bears, other than pregnant females, do not hibernate, but they do spend several months fasting in a state of "walking hibernation." As the largest of the bears--living in the harshest climate--polar bears undergo the most dramatic changes in weight... Courtesy U.S. Fish and Wildlife Service
Does a bear run to the back of the den?
Muscles--Without the Workout When Hank Harlow, a physiologist at the University of Wyoming, enters the den of a hibernating black bear, the bear often gets up and runs to the back of the den. That's true even if the bear has been lying there for 110 days... Courtesy Paul Iaizzo
How does a hibernating bear's metabolism work?
Their body uses very little energy and nutrition during actual hibernation, so it produces very little waste and requires very little "input" to keep metabolism working properly .
Why did the bears wake up in the spring?
In the fall he did not come back. The next spring they woke up one night because their dogs were making a racket. They went outside and saw a bear next to their line of tethered sled dogs, fearing that the bear would eat them.
What happens to a cub when she is hybernating?
When she was hybernating she was consuming the fat in her body, which contains a certain amount of water that she converted into water for herself, and milk for the cubs. The other thing that happens during hibernation, and this is the kicker, her body converts her urine into protein, and consumable water and the process continues.
What did the hybernating woman eat?
When she was hybernating she was consuming the fat in her body, which contains a certain amount of water that she converted into water for herse
How long do grizzlys hold their nuggets?
This is by no means customary behaviour for the species, as they usually do pretty well holding it in for the 7–8 months they snooze. But when the going gets tough, a Grizzly ain’t afraid to sneak outside its cozy den to drop a Grizzly nugget. But if it is a female with young, it may decide to hold it in instead, because parenting.
Do bears live in the winter?
Lots of bears do live in places where they can put on enough fat thru the summer and fall to survive on their stored fat thru long cold winters, places where they wouldn’t be able to find much if anything to eat thru the cold season.
Can a bear wake up?
So, hikers, beware: a hibernating bear can wake up at any time, especially when it’s under disturbance, or when it’s been awaken by an unwelcome noise. As such, hibernating bears don’t find themselves at all vulnerable to predation, particularly since the idea of trying to predate on a bear is a suicide call, even for a strong pack of wolves or a well-built cougar.
How do bears survive in the winter?
Surviving a winter without food or water requires fuel, and a bear fuels its body on the fat reserves it acquired during the previous summer and fall. Bears do not eat, drink, urinate, or defecate while in the den. Fat is metabolized to produce water and food, but instead of defecating or urinating to eliminate waste, bears recycle it. Their kidneys shut down almost completely and urea, a major component of urine, is recycled into proteins that maintain a bear’s muscle mass and organ tissues. Without the ability to recycle urea, ammonia would build up to toxic levels and poison the animal. Since they are living off of their stored body fat, bears also have very high levels of cholesterol in their blood.
When do bears hibernate?
In the Katmai region, most bears go to their den and begin hibernation in October and November. Hibernation in bears is most likely triggered by a shortage of high calorie food as well as hormonal changes. After a summer and fall spent gorging on food, a bear’s physiology and metabolism shifts in rather incredible ways to help them survive several months without food or water.
What is the normal temperature of a bear?
When hibernating, a bear’s body temperature remains above 88˚F (31°C), not much lower than their normal body temperature of 100˚F (37.7°C). This is unlike other hibernating mammals such as ground squirrels whose body temperature drops close to freezing. A bear’s heart and respiratory rates, however, drop dramatically. They average only 1 breath per minute with a heart rate of 8-10 beats per minute in hibernation.
Do bears sleep in the winter?
In the depths of winter, when Katmai’s landscape is covered in snow and ice and the wind is howling fiercely, bears are nestled snug in their dens and sleep soundly. They feel no thirst or hunger at this time. Bears are survivors with a very special adaptation—hibernation—that allows them to survive harsh wintertime conditions and famine remarkably well.
