Fauna of Ireland

The fauna of Ireland comprises all the animal species inhabiting the island of Ireland and its surrounding waters.

This table uses figures supplied by the National Parks and Wildlife Service.

Only 26 land mammal species are native to Ireland, because it has been isolated from the European mainland (by rising sea levels after the Midlandian Ice Age), since about 14,000 BC. Some species, such as the red fox, European hedgehog, stoat, otter, pygmy shrew, and badger are common, whereas others, like the Irish hare, red deer, and pine marten are less common and generally seen only in certain national parks and nature reserves around the island. Some introduced species have become thoroughly naturalised, e.g. the European rabbit, grey squirrel, and brown rat. In addition, ten species of bat are found in Ireland.

In the Ice Age (which included warm spells), mammals such as the woolly mammoth, wild horse, giant deer, brown bear, spotted hyena, Arctic lemming, Norway lemming, Arctic fox, European beaver, wolf, Eurasian lynx, and reindeer flourished or migrated depending on the degree of coldness. The Irish brown bear was a genetically distinct (clade 2) brown bear from a lineage that had significant polar bear mtDNA. The closest surviving brown bear is Ursus arctos middendorffi in Alaska.

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