As winter bites we turn up the central heating but some creatures have a cosier solution. Cheshire Wildlife Trust’s Katie Piercy reports on some of the great hibernators
The average human will sleep for roughly a third of their life, however this may be nothing compared to those that choose to forgo part of the year entirely. Hibernation may not be exactly the same as a nice long sleep, but it does share many similarities, with creatures lowering their heart rate and body temperature in order to save energy during the leaner months of the year. So while winter may at times seem devoid of life you’d be surprised who may be tucked away in your garden, your shed, or even your home.
Peacock butterfly
Butterflies may appear as flimsy and frail as pieces of tissue paper caught in the breeze, but these brightly coloured sun-worshippers have a surprisingly resilient spirit. The painted lady undertakes a mass migration every year, travelling at altitudes of over 500m to complete a multi-generation 9,000 mile trip from tropical Africa to the Arctic Circle, with the UK as just one of their stopping off points. For many butterfly species however an alternative to such risky journeys has been found.
Brimstone, comma and peacock butterflies are just a few UK species which sleep away the winter in their adult forms, hidden beneath the bark of rotten trees, in wood piles, or even in garden sheds. In their torpid state these hidden treasures can be at risk of predation by some of those winter carnivores looking for a few tasty morsels to get them through the long cold days.
Camouflage is a common defence; with species keeping their brightly coloured inner wings tucked away while their outer surface often displays a duller wood-textured cover. Although this often proves effective when left undisturbed, studies have shown the peacock butterfly has a particularly dramatic fashion of insuring any noisy critters are quickly sent on their way. The four brightly coloured spots which flank the inside of the peacock wings mimic the eyes of a much larger creature. When startled, the insect, which hibernates with closed wings, flashes would be predators with these vivid markings, while emitting a loud hissing sound. Studies have shown that this behaviour allows more peacock butterflies to survive direct contact with predators than other hibernating UK butterflies.
Should you disturb this feisty creature yourself simply leave it where it has chosen to sleep, or take it to a suitable alternative, somewhere cool and safe with an easy escape route if it doesn’t agree with your choice.
Pipistrelle bats
The common pipistrelle is one of the UK’s smallest bat species, fitting comfortably into the inside of a matchbox. In the summer these tiny creatures can polish off over 3,000 midges in a single evening, however in the winter when flying insects are rare they have little to sustain the high energy activity of flying. The simple solution to their problem is a prolonged period of hibernation, usually lasting from November to March. A hibernating bat may reduce its heartbeat to just a few beats a minute and sometimes takes less than one breath an hour.
Only two species of bats in the UK hang upside down, the lesser and greater horseshoe bats, the rest prefer to squeeze themselves into small crevices, often crowding together in large numbers to keep warm. During hibernation they prefer to be somewhere where the temperate will remain fairly constant, and no disturbance will occur. This often means they choose caves or man-made equivalents such as cellars, garages or roof spaces. It is important not to wake bats during hibernation, as this uses up large quantities of their resources.
Bats can often live happily alongside humans causing little disruption or damage, however remember to seek advice if any issues should occur as moving or killing any type of bats is illegal.
Queen bumblebees
While the buzzing of bees may be as synonymous with summer as ice-cream and flip flops you may be surprised to know that queen bumblebees are still present throughout winter. Though the rest of her colony only lasts for a season, the queen will make herself at home beneath the ground or in areas of loose soil such as compost heaps. Each queen will only survive a year, meaning that hibernation can take up a huge amount of her lifecycle. In order to survive cold conditions these tiny insects produce a kind of ‘anti-freeze’ which they circulate throughout their body to prevent ice crystals forming in their cells.
It’s common to uncover a hibernating queen while pottering in the garden, and the easiest thing to do is to recover them with the materials which have been removed, loosely so that she can dig herself out when the time comes. If the bee is already active, a dose of sugar solution can give her the boost to get on with her ‘buzzy’ schedule.
Great crested newts
Cheshire is one of the best places in the UK for spotting a great crested newt. These enigmatic protected amphibians spend much of their lifecycle in and around ponds. It is important for the ponds to be fish-free, as these hungry predators make short work of the newt’s precious eggs. Like all UK amphibians the great crested newt must hibernate during the winter months, often choosing log piles, old burrows or spaces under stones as its preferred winter home. If you have newts, frogs or toads in your garden pond it can be important to leave wild patches with twigs and leaf litter close by as a safe refuge once the colder weather moves in.
Hedgehog
Perhaps the first species anyone thinks of when naming hibernating animals in the UK, the hedgehog does indeed enjoy a good snooze during the winter months. For these small mammals hibernation is entirely weather dependant, with individuals sleeping anywhere from a few weeks to six months. They will also practice a kind of summer hibernation, known as estivation, if temperatures become too high. In this time hedgehogs can drop their heartrate by 90%, although they may raise it again if they become too cold.
The traditional image of a tightly curled ball of spikes, nestled inside a bed of leaves is rather accurate for our garden friend, making it important to leave some areas of brash or leaf litter for our hogs to use as bedding. With better fencing in place in many gardens these nightly visitors often suffer exclusion, unable to access those tasty slugs and snails happily munch away on a home-grown lettuce, so why not create small holes or openings so as to let in this tiny knight in shining armour?
Sleep tight
Those are just a handful of the critters possibly snoozing away within your compost heap, below your woodpile or in the ivy on your walls, with many other creatures sleeping away the winter in our gardens, our homes or our countryside.
The best thing you can do for these sleepy heads is leave them a little place to call their own, whether that’s within the dead stems of the plants in your flower patch, or the pile of branches in your wild corner.
And if you do accidently disturb one of these sleepers remember to put back their blanket, turn the alarm on snooze, and let them dream away the frosty days until you can meet them again on a lovely spring or summer’s day.
Help the trust
The work done by the Cheshire Wildlife Trust is dependent upon the support of its members. You can find details on how to join online at www.cheshirewildlifetrust.org.uk/membership. Remembering the Trust in your will could ensure that the Cheshire Wildlife Trust can continue to protect Cheshire’s wildlife and wild places for generations to come. Go online or call 01948 820728 for more information.
