About 400 bird species have been recorded in Ireland. Many of these species are migratory. There are Arctic birds, which come in the winter, and birds such as the swallow, which come from Africa in the summer to breed. Many birds which are common residents in Britain and continental Europe are rare or unusual in Ireland, examples include the tawny owl, willow tit, marsh tit, nuthatch, and all woodpecker species except the recently established great spotted woodpecker. These are birds which do not move great distances and their absence may be due to Ireland's early isolation, but also Ireland's mild weather means early breeding and choice of best habitats which gives residents an advantage over visitors.