The spiky invader of the forest edge is covered in thousands of sharp, hollow spines that it uses for defence. When threatened, it curls into a tight, spiky ball, protecting its soft head and belly. The face and belly are covered in soft, brown fur. It has small, dark eyes and a pointed snout that it uses to sniff out food. These animals are the insect specialists of the pest world. They eat beetles, caterpillars, worms and anything else they can find. But they also eat the eggs and chicks of ground-nesting birds, the eggs of lizards and the native insects that live in the leaf litter. A single hedgehog can eat dozens of native weta in a night, and they are one of the main predators of the eggs of the banded dotterel and other shorebirds. Hedgehogs were brought to New Zealand by European settlers who missed the familiar animals of home. They were released in gardens and parks, where they thrived. Now, they are found throughout the country, from the coast to the high country. To see a hedgehog is to see the nostalgic pest. A spiky, cute, familiar animal that does more damage to our native insects and birds than most people realise. The hedgehog's impact is most severe in braided riverbeds, where ground-nesting birds lay their eggs on open gravel. A hedgehog walking through a colony at night will eat every egg it finds. It will also eat the chicks, if they are small enough to catch. In some areas, hedgehogs have become the primary predator of endangered shorebirds, surpassing even stoats and ferrets. They are also devastating to native invertebrates. A single hedgehog can eat hundreds of weta in a summer. In forests where hedgehogs are common, the sound of the night is quieter. The insects are gone, eaten by a spiky invader that no one wanted to hate.