Witchcraft and hares in Scandinavia.

In the Nordic countries notions of connections between witches and hares belong to three different tradition complexes. The first one is known from Denmark and sporadically from Southwest Sweden and southern Norway. It is a Continental belief, which is also current in the British Isles, namely the belief that a witch can transform herself into a hare and in that shape perform various mischievous or malignant deeds.
http://www.jstor.org/stable/1260796