Harper Asprey Wildlife Rescue encouraging through knowledge a natural balance

Man has long since given up accepting the seasons and constantly strives to battle with and overcome them. This futile war leaves us quite clearly at the bottom of the league table of contributions to the well-being of our planet.

Hibernation is a behaviour which animals have evolved to survive harsh weather; but temperature is not the only factor; indirect effects of temperature can cause ingenious chain reactions and behaviours that are simply out of this world.. Some insects hibernate because there are no plants in the winter and large predators hibernate because there are no insects. Lack of or no food is the main reason for hibernation.

 

 

Adaptation has caused many of our species to evolve complicated life styles in order to survive. I really sometimes wonder how intelligence should be measured. These tiny creatures that constantly adapt always save energy and survive against the odds and in total balance with Nature; surely in some ways they should be considered the most intelligent lifeform on the planet. Maybe life should be that simple and focused for us to ultimately reach a balance.

A long-term state of suspension of life-functions is known as Diapause or Dormancy. This simply means that if conditions are just too bad, you pause. This can occur at any stage in an insect’s development and is again a tool to cope with no food and little heat. This state can be entered into by eggs to. For instance, the praying mantis survives the winter as an egg and emerges in the Spring. Larvae of butterflies, such as Swallowtails, spend winter as chrysalids. Admiral butterflies hibernate as adults, often in lofts and houses to re-emerge in Spring. Most other butterflies and moths survive as pupae through our winter. Some insects such as mosquitoes, dragonflies and damselflies can spend their larval stage in the water of ponds and streams.

Unlike mammals such as hedgehogs and bats, insects don’t have the benefit of body fat. Most insects’ bodies would turn to ice if they tried to survive the freezing conditions of the the winter. So what do insects do in the winter?

Ladybirds hibernate, often in large groups sometimes numbering thousands. Different species hibernate in different places. Some shelter under tree bark, others sleep under leaf litter waiting for Spring to arrive.

Ants head down below the frost level and survive until the spring on their stored food. Spiders mate in Autumn and this is normally when we find them in our houses, It’s usually a male looking for his female to mate. It’s a hazardous job when so many people do not like them. After they have bred they will hibernate until the following Spring when food again is abundant.
So what happens to all the animals that feed on them ?
The hibernation season starts for us around October. We know it’s arrived here in Harper Asprey Wildlife Rescue, because our doors are open and the flies that have become the pain of our life through the Summer in the rescue have now all gone.

 

The drastic drop in insect activity means the insect feeders have no food. Bats start to hibernate in October not only because the cold weather has arrived but actually because there is no food. These cuddly little fellows find trees to huddle up in and spend their winter in a state known as torpor. Their body reduces in temperature and the huddle of furry friends prevents them from freezing. Their heart rate slows down and energy is preserved. Most bats breed during this hibernation period.

 

 

Hedgehogs spend much of the Summer, while abundant food supplies are around, feeding to gain body fat to survive the lean months. Hedgehogs hibernate from October until the Spring - although these prickly fellows sometimes wake during the long sleep and find food for short periods. The insects and the caterpillars they hold so dear are no longer available. Like the bats, their heart rate slows to around 20 beats a minute, and this enables them to preserve their fat supplies. The hedgehog will build a nest from leaves and grasses to spend the Winter in. Due to the timing, bonfires become a welcome site, so please check them before you light them on Firework Night.

Many insects combat the cold by making their own anti freeze. In the Autumn insects produce glycerol, which increases in the hemolymph (the fluid in the body tissues and cavities of insects which transports nutrients.) Glycerol gives “super cooling” ability to the insect, allowing their body fluids to drop below freezing point without causing ice damage. Glycerol lowers the freezing point, making insects more cold tolerant; it protects tissues and cells from damage during very icy conditions. In spring the glycerol levels will drop again.These fascinating and complex creatures are not only incredibly adaptable and ingenious - they are also the basis of all our food chains, and without them we simply would not be here.

 

Frogs and toads usually also start their winter sleep in October for much the same reason - no food. They are cold-blooded, and usually hibernate in the mud or in deep burrows when their staple diets of slug and bugs are all gone. In North America and Canada the grey tree frog actually freezes during hibernation and turns blue, giving real meaning to “turning blue with cold.”

 

 

Our grass snakes head for deep leaf litter, compost heaps and rock piles for their deep sleep. Our only venomous snake, the striking Adder, heads for burrow and warrens to spend his winter. Our legless lizard, the slowworm, sleeps under deep piles of leaves or within tree roots and in crevices of banks. As with all our snakes they can be alone or in groups. Some snakes establish ‘hibernacles’, and these sites can sometimes hold hundreds of snakes at any one time. The Smooth Snake chooses burrows and always tends to be in groups. Their populations are localized and they seem to stick together.

 

 

Our foxes need daily food and water and their thick coat, too often stolen by humans, keeps them warm. Their food supply is still there so they do not hibernate. Badgers can have short periods of sleeping during bad weather if they have enough food and fats. Badgers do take food into their setts at these times of the year.

So as you can see, hibernation affects a multitude of creatures in different ways. If you disturb a hibernating animal contact your nearest wildlife rescue, as specialist care will be needed to help it through hibernation. In some cases it may need to be slowly brought out of hibernation.

Enjoy your winter and Christmas and remember, while you are busy decorating your tree, there may just be someone very special sleeping deep within it.