A method for assessing the relative importance of seabird breeding colonies

Evaluating the importance of seabird breeding colonies in a national or international context is an essential part of conservation planning. A method for assesiing seabird sites, and for selecting a series of key colonies, is described, following Ratcliffe's (1977) guidelines. The present study uses seabirds in the Republic of Ireland and data recently collected for a breeding seabird inventory. The method is suitable for use on seabird populations elsewhere. The inventory listed over 400 sites, of which 133 were identified by this study to be of national importance to conservation. Among these were 11 internationally important colonies. Thirty-one of the colonies were selected as key sites of special importance.