Bears are not true hibernators? A true hibernator, like a chipmunk, enters a state of hibernation and then will not wake until their biological clock tells them to, regardless of external stimuli. Bears do not hibernate. Instead, they enter a state of torpor. Torpor is a state in which bodily functions such as respiration rate, heart rate, and digestive rates slow dramatically. An animal in a torpor may often appear groggy and uncoordinated but they are completely aware of their surroundings and are capable of recognizing and escaping danger should it arise. Therefore, bears are completely aware of giving birth (they are not oblivious as many believe) and they are aware of the comical antics of their young in the den. They are aware of odd noises passing by their dens and will leave the den if they feel threatened and the exits are not blocked. They will also leave the den in the middle of winter should it become no longer suitable. For example, if we get a warm weather spell and a lot of snow melts, bear dens that are located in low, wet areas will flood. When this happens, regardless of what month it is, the bear may exit the den and roam in search of a new place to relax for the remainder of the winter.
Box turtles and some other reptiles and amphibians are capable of surviving freezing? Box turtles may dig down 19 inches to form their hibernacula. In Maine, the frost line is 48 inches down. Luckily, box turtles have been found to survive over half their body freezing for short periods of time. Box turtles have been recorded in hibernation with core body temperatures as low as 25 F and as much as 58% of their total body water content ice. They have also withstood freezing periods for up to 73 hours.
Black-capped chickadee calls are lengthened relative to the threat they perceive? By varying the number of dees on the end of the chick-a-dee-dee call, chickadees convey to other birds the seriousness of a threat. For example, a chickadee keeping an eye on a squirrel may have only two or three dees on the call, whereas a chickadee warning about an approaching cat may tack on up nine dees. The appropriate call length is not determined by the size alone of the animal the chickadee is warning about but by the actual threat. For example, the chickadee warning about a predator like the cat will call with more dees than a chickadee telling about an approaching deer. Even though the deer is considerably larger than the cat, deer are not predators and are not a threat to the chickadee.
There are ten documented species of freshwater mussels in Maine? Most of Maine’s freshwater mussel species require running water and prefer streams and rivers. The two most commonly found in ponds and lakes are the Eastern floater and the Eastern elliptio. When left alone in a stable, suitable environment, mussels are extremely long-lived. The lifespan varies between species, but in general freshwater mussels can live from 60 to over 100 years old.