The hedgehog (Erinaceus europaeus) is an insectivorous mammal, whose closest relatives in Ireland are the pygmy shrew and the introduced greater white-toothed shrew. Hedgehogs feed on insects, spiders, slugs, and occasionally frogs, bird’s eggs and small mammals, which they find while foraging in pasture, hedgerows, broadleaved woodland and sometimes on arable land; they especially like to feed in the “edge habitats” on the borders between these areas. The most distinctive feature of the hedgehog is the dense coat of spines on its back, which are actually strengthened hairs are used for defence against predators such as foxes, badgers and dogs. It is active from around March to October, when it has to feed voraciously to build up enough fat reserves to survive through hibernation the following winter- it is only mammal in Ireland apart from the bats to experience “true hibernation”. It is unknown when hedgehogs arrived in Ireland, as they were first recorded here as recently as the 1200s, so it is possible that they were introduced, but if that is the case they have long since spread and become naturalised. For more information on hedgehogs, please read this article by Amy Haigh.
Although it is probably one of the most recognised and well-loved Irish mammals, familiar to school children all over the country, the hedgehog is not particularly well-studied in Ireland. In particular, very little is known about its distribution and population here. In the UK, it is estimated that the population of hedgehogs has declined from about 30 million to 1.5 million between the 1950s and 1990s, which is possibly due to habitat loss and fragmentation from intensification of agriculture and urbanisation, and road traffic accidents. There is currently no data in Ireland to say if the hedgehog population has experienced the same decline.
The MISE Project are currently testing the method developed by The Mammal Society in the UK for assessing the presence or absence and population of hedgehogs (see here for details about their project). At present, we are trialling this method across Co. Waterford to detect hedgehogs where they have not previously been recorded. Thus far we have mainly done this in schools (see here for Mammals in Schools page), and we have written up a simple set of instructions for hedgehog footprint tunnels. If you are interested in helping with this project, please contact Andrew at email@example.com or 086-4135544.