How Do Cold-Blooded Animals Survive the Winter?

these physiological advantages. Apart from a handful of species like the monstrously big leather back sea turtle, very few reptiles or amphibians are able to keep their bodies at a constant temperature, and since they can't warm themselves up, these creatures must extract heat from their environment. But what happens

when that environment gets colder? How to frogs, snakes, and turtles make it through the winter months in places that see blankets of snow, iced over lakes and subfreezing temperatures year after year. A lot of reptiles and amphibians undergo periods of extreme seasonal inactivity. When the weather gets colder. They may experience decreased heart rates, slowed metabolisms, and lower overall body temperatures. Scientists disagree over what to call this state.

Everyone accepts that it's some kind of dormancy, but while some experts classify it as hibernation, others referred to it as brumation. Dormant snakes generally hold themselves up in winter dens. These shelters may take the form of an abandoned rodent burrow, an exposed crevice on a rock face, or some naturally

occurring hole underneath a tree. Various snakes have also been known to turnhousehold basements or garages into winter lodges in seasonally cold areas like Canada and the northern United States. Snakes must choose their dens with care. Ideally, a winter hangout spot will descend below the local frost line, the maximum depth beneath the ground at which soil freezes. Hiding out underground is the survival strategy of choice for lots

of tortoises and turtles as well. Some species, such as the gopher tortoise, dig their own burrows, but it's not uncommon to find the shelled reptiles occupying pre dug unoccupied rodent holes. Now, a hibernating lack bear can sleep for more than one hundred days straight without consuming any food or water. Reptiles tend to be more active during hybernation

or romation. When a midwinter warm spell comes along, they'll use it as an opportunity to crawl up to the surface, bask in the sunlight for a little while, and maybe grab a quick drink. Reptiles are perceived as loaners, a reputation that isn't entirely deserved. Consider the Eastern diamond back rattler, who doesn't seem to mind collaborating with gopher tortoises. Members of both species will sometimes go dormant together inside the

same burrow. Likewise, snakes often share their dens with other snakes. Garter snakes are famous for hibernating in huge groups that may consist of hundreds or even thousands of individuals. One Canadian den reportedly contained no fewer than eight thousand snakes. Indiana Jones and other videophiles will want to keep their

distance as snakes go. Garters are remarkably cold tolerant. One species can even survive the unbelievable experience of having of the liquid water inside its body freeze solid, but only if it's allowed to thaw out after a few hours, but the wood frog takes freeze tolerance to a whole new level. A North American native, this cold weather warrior has the distinction of being the only amphibian in the

Western hemisphere whose range extends into the Arctic Circle. Every autumn, wood frogs bury themselves under a thin blanket of leaf litter on the forest floor. There they will remain dormant for up to eight months. In the process, the heart temporarily stops beating and the frogs enter a state of suspended animation. Left to the mercy of the elements, the amphibians freeze at temperate and polar latitudes. Fortunately, the liver pumps loads of glucose into the bloodstream, while urine is

retained within the body. All that helps keep the cells from drying out, which is what would normally happen during the freezing process. Therefore, a full six of all the water in a wood frog's body can become frozen, and the amphibian will still live to rib it another day. Moreover, the frog may be kept frozen at negative eighteen degrees celsius or about zero degrees fahrenheit, for as long as two hundred and eighteen days. Another example of this cool

survival strategy can be found in far North Russia. The Siberian salamander lives in areas that get temperatures of negative fifty degrees celsius that's negative fifty eight fahrenheit or lower. To stay alive, it hibernates underneath logs, vegetation, and snow banks. A compound in their bloodstream keeps the critters alive when

the majority of its body water turns to ice. Terrestrial amphibians with poor digging skills, like the wood frog, tend to either hibernate in pre existing burrows or fine shelter at ground level. Good burrowers, such as the American toad and spotted salamander, proactively dig winter holes from themselves that extend below the frost line. For aquatically inclined amphibians, there's

another option. Bullfrogs are lake and pond denizens who find oxygen rich bodies of water and spend their winters imprisoned under the surface of ice that forms there. Painted turtles employ a similar strategy. Reptiles generally use their lungs to breathe, but some semi aquatic turtles can also absorb waterborne oxygen through their skin over wintering. Painted turtles do this extremely well, Plus they can lower their metabolic rates to the tune

of each winter. That's how they stay alive with the thick sheets of lake ice for months on end. Sometimes you can even see them swimming around under the frozen barriers. But why go through the hassle of skin breathing when you can turn your snout into a snarkle. In January, the Internet was greatly amused by some North Carolina alligators whose noses were seen poking up out of a frozen pond. Gators can't survive being trapped in icy water for much

longer than a week or so. For long term winter lodgings, they construct deep burrows out of waterside mud. Today's episode was written by Mark Nancini and produced by Tyler Clang. For more on this and lots of other warm topics, visit our home planet, how Stuff Works dot com