Ever wonder how wildlife can survive extreme temps and weather conditions? Here's a little piece of the puzzle that may bring a little clarity to the subject. It doesn't mean it's easy for them but they have some inherent capabilities that our pets do not possess.
I’ve often wondered how non migratory birds and other small mammals make it thru our harsh winters.
I would expect to see lots of little dead creatures scattered about the ground during merciless winters when temps are brutal and food is scarce. Fortunately we don’t see that, but how do they survive?
One survival tactic, known as Topor, is an involuntary state that is dictated by extreme conditions. It has a likeness to hibernation but is usually short in duration. It may occur just thru the night or may even occur during the day depending on the feeding schedule of the animal. Their breathing rate, heart rate, body temperature and metabolic rate drop significantly when they become inactive allowing them to enter a deeper sleep and conserve energy. The awakening process, triggered by ambient temperature and food availability, takes about an hour and necessitates vigorous shaking and muscle contractions. While this does expend quite a bit of energy, it’s offset by the amount saved in the torpid state. So what animals use this survival tactic? Despite the common myth that bears hibernate, they in fact go into this “light hibernation” called topor.
*Raccoons, skunks, chipmunks, bats, hummingbirds, doves, chickadees and mice are among some other familiar animals that do so as well.
Hibernation is a more widely recognized term however I believe there is confusion about which animals actually enter into this voluntary state. Like Topor, it is a tactic used to conserve energy when food is scarce and temperatures are low. It is triggered a shorter length of day as well as hormonal changes indicating a need to conserve energy. It is the true deep sleep. Animals will usually store fat in readiness for hibernation which helps them survive the long cold winter. Occasionally they may wake up briefly to drink, eat and/or defecate but it can take hours to be aroused from a hibernation state which uses up quite a bit of reserved energy.
*A few common hibernating animals are: most turtles, many frogs & toads, snakes, groundhogs, ground bees, bumblebees (but not honey bees). Interestingly, the ‘common poorwill’ is the only bird that truly hibernates. It can be found out west from British Columbia all the way down to Mexico.
Estivation is similar to the process of hibernation and topor but is relied on by some animals to survive the hottest and driest months. Many animals, including invertebrates and vertebrates, will employ this tactic.
*Examples of animals that estivate are: Crabs, mollusks, Crocodiles, mosquitos, some salamanders, desert tortoises, and some hedgehogs.
Why don’t we see many insects in the winter? Do they all die? Spiders are cold blooded and most can hideaway for winter months. Despite what appears to be a waiting line at my door as the weather turns cold, they are not attracted to indoor warmth. They’re probably hiding under the doormat, or crack around the foundation which is a common place for them to winter. Many other invertebrates & insects including beetles and wasps go into a period of suspended development known as Diapause. When the going gets rough they take a break!
This is just a minuscule of information about the ability of wildlife to push thru rough conditions but in a nutshell they are genetically programmed for adaptive physiological changes.