The spread of the Bank vole Clethrionomys glareolus in Ireland

Abstract
The discovery of the Bank vole Clethrionomys glareolus in Ireland and the published information on its spread are reviewed, and the results of a complete resurvey of its distribution, in 1982, presented. The rate of spread is extremely variable and somewhat unpredictable. Over suitable habitat—agricultural land with hedges and other cover (and sometimes mountain valleys)—spread may average 2–4.5 kmyr‐1 but can sometimes be very much slower. This might be influenced by the type and extent of hedges and of permanent pasture. High ground and moorland usually prevent spread but there have been dramatic exceptions. In 1982 Bank voles occupied probably the whole of Co. Limerick; most of Co. Kerry, with the exception of substantial parts of the mountainous peninsulas in the southwest and contiguous interior; a large part of Co. Cork, though not the south‐east and again excepting portions of the mountainous south‐west, together with a substantial strip of east Co. Tipperary, and the south‐east quarter of Co. Clare.