Another Life: The prickly problems of life as a hedgehog

The last hedgehog I saw was, as in Pam Ayres’s requiem, “squashed . . . and dead . . . and flat” on the boreen, like someone’s long-forgotten purse.

More happily, a good friend has one that keeps returning at night to his yard, where a kennelled dog lies comfortably with his nose in the opening and his unlicked bowl close by. There is a sudden volley of barking – this at 1am or 2am – and my friend must go out with a long-handled shovel, retrieve the curled-up animal from beneath the dog’s paw, and gently lob it back into the dark. “You’d think it would learn,” he says.

When we had Aylesbury ducks, delightful but wild in spirit, a frenzy of quacking in the middle of the night and a glimpse of whirring white wings took me out to find a hedgehog plundering seven eggs laid deep amid brambles and meadowsweet. It took the long turf tongs to extract him, for overnight confinement in a tea chest.

Since then the few signs of hedgehog on our acre have been the occasional overheard snuffle and wheeze, or a trail in long grass – a wavering furrow confirmed by a casual dropping, small, jet black and gleaming with fragments of beetles. The grass this autumn having grown at a great rate, I explored our likeliest patch of lawn and found, indeed, a furrow, but one broad, straight and purposeful and fringed, at intervals, with divots scooped from the earth. Such familiar spoor of a badger seems to rule out the chances of hosting a live hedgehog of our own.

Predation of badgers on hedgehogs, leaving a scooped-out spiny skin, is well attested. In the early days of Eye on Nature a Co Wicklow reader, woken in the night by what sounded like a baby crying in the garden, went out with a torch to find a hedgehog pinned under a badger. She hit the attacker, which ran off. “The skin on the poor little hedgehog’s face was completely ripped off,” she wrote, “and it kept whimpering like a child.” She nursed it back to health and later released it into the undergrowth.

Conservation zoologists at Oxford University have shown that hedgehogs steer well away from locations that smell of badgers – such behaviour might even be bred in their genes. There is now research to see how they respond to local clearances of badgers, with or without tuberculosis. There would be extra feeds of earthworms (hedgehogs extract them "with a gentle rocking motion") but also, perhaps, more attacks on ground-nesting birds and their eggs. In 2011 a reader in Co Antrim reported seeing a hedgehog kill a male blackbird and take more than an hour to eat it.

Hedgehog death by traffic probably far surpasses that from badgers, and roadkill figures are sometimes used to judge trends in national hedgehog populations. Such sightings reported to biology.ie – 829 this year, as I write – are monitored by the National Parks and Wildlife Service.

Slow progress
Studying hedgehogs in the wild can certainly be difficult. Dr Amy Haigh of University College Cork recently reported, in the Journal of Negative Results, her problems in locating hedgehogs to fit with radio tags. Failing to make progress through asking farmers and rural locals, or using infrared cameras, rabbit traps or footprint boards, she had most success from searches after dusk, four nights a week, with a two-million-candlepower spotlight.

After weeks with not a hedgehog in sight, she finally found some at three per hectare in one Co Cork location and, having lamped them 17 times over 48 nights, trapped eight to fit with radio tags. They were tracked until their hibernation in November 2008.

Haigh’s work over recent years, with two UCC colleagues, has added substantially to what we know about an animal that may have arrived with humans as late as the 13th century, perhaps for food, or for its spiny skin, to use in carding sheep’s wool.

In our mild climate the hedgehog’s breeding period is generally from April to July, but newly independent animals, up to six weeks old, have been seen up to the end of October, and some females may have two litters in the year. Hibernation dates, too, have drifted. Later autumn foraging – mainly for insects and their larvae – means less weight loss while ticking over sleepily under the leaves and emergence perhaps as soon as March. Letters to Eye on Nature tell of hedgehogs rousing in winter to forage by daylight; they may even move house (or hibernaculum) from one pile of leaves to another.

A hedgehog is capable of living for up to 10 years, but most, in the wild, don’t survive beyond two. In one study of Ireland’s roadkill, about half the dead hedgehogs were less than a year old, with adventurous males the more vulnerable. In gardens, too, the animals may fall victim to machines. In clearing up for winter, just be careful where you strim.