Damp autumn weather has brought two seasonal phenomena to Waterfurlong - fungi and molehills. As every morning revealed new earthworks in the orchard, I realised how little I knew about Britain’s secretive little mole.
The word ‘mole’ is late Middle English and probably derives from ‘moldwarp’, meaning ‘earth thrower’ - ‘mouldywarp’ was a colloquial name for the mole in many rural areas until quite recent times. The male is a boar, the female a sow and the collective a labour of moles. It is the only mammal to live its whole life underground - sleeping, breeding and feeding in its tunnels. The mole has an unusually high percentage of red blood cells, enabling its survival in such a low-oxygen environment.
There are estimated to be 35-40 million common or European
moles in mainland Britain and despite once being trapped for its luxurious, velvety pelt, talpa europaea is a successful species by any measure. The mole is a solitary, territorial animal, living a strange life of seclusion in its dark, subterranean complex, with a surprisingly large home-range of about an acre. Its original habitat was deciduous woodland, but the lush, well-worked gardens of suburbia provide the mole with an even better home, much to the chagrin of lawn-owners across the land.
In summer the mole searches for worms and grubs in shallow tunnels just beneath the ground, creating a pattern of ridges in the grass. In autumn it moves deeper into the earth, shovelling up the characteristic mounds that wreak havoc in neat garden plots. Often the mole will centre its foraging tunnels around a mature tree in order to access insect larvae which feed on the root system. As winter deepens and the ground surface freezes, its visible activity diminishes, giving rise to the myth that moles hibernate. But far from enjoying months of inactivity, the mole is one of the hardest-working creatures on the planet; it operates in relentless shift-cycles – four hours work followed by four hours sleep, all day, every day, all night, every night, like clockwork.
When off duty the mole sleeps upright with its head tucked between its forelegs. When awake its energies are spent patrolling its tunnels to hunt for worms, grubs and larvae, guarding its territory with scent markers as it goes. The mole needs to eat about 20 worms a day – half its body weight – to survive. If it can’t collect sufficient food from its existing tunnels it starts digging supplementary ones and an unusually high number of molehills is often a sign the earth-worm population is struggling. The mole can dig up to 20 metres of tunnel a day, using its spade-like forepaws in a breast-stroke movement. Its smooth coat helps it glide through the soil and its mouth and nose are protected from debris by a down-facing position.
The mole’s treatment of its earthworm prey is particularly gruesome. The mole paralyses the worm by injecting a toxin behind the head and then carries it to one of its underground ‘larders’. These larders have been found to contain as many as 1,000 paralysed, fresh worms. When ready to eat, the mole first runs the worm through its feet to squeeze soil and debris from the gut. Although the mole’s diet predominantly comprises insects, it will occasionally catch frogs and mice – like the hedgehog, the mole can move more quickly than we generally imagine.
With the arrival of spring, the male mole goes in search of a mate and creates a grass and leaf-lined nesting chamber in which the female gives birth to a single litter of between two and seven. The young, born hairless, are large at birth relative to the size of the mother and within four to five weeks are weaned and sent off to live their own solitary lives. They establish independent tunnel systems nearby, either through excavation or by adopting abandoned runs.
Hibernation is not the only misconception about the life of the mole; there is a common belief that the creature is blind, deaf and dumb. None of these is true. The mole is light-sensitive on the rare occasions it surfaces but is not blind. Its ears are situated internally behind its shoulders, so the mole’s snout acts rather like a sound tube and it relies more on touch than on hearing; sensory hairs sited along its body help the mole to navigate in the darkness. And whilst it can hardly be described as a noisy creature, the mole will scream when frightened.
Recent research has revealed further surprises. For example, the mole is an adept swimmer and if its burrow is flooded it will swim off to new pastures. Perhaps the most remarkable aspect of mole behaviour though is the males’ aggression towards one-another; authority on mole behaviour Kenneth Mellanby reveals ‘Moles hate their own species! If two are confined together they will fight to the death!’ (3)
SOURCES AND ACKNOWLEDGEMENTS:
(1)Photograph © Beeki courtesy of Pixabay
(2)The Secret Life Of An Enigmatic Pest, Independent 19 June 2010
(3)The Mole by Kenneth Mellanby, Collins New Naturalist Series, 1971
Copyright © Karen Meadows 2018