Key points are not available for this paper at this time.
A survey of quarry-nesting Peregrines conducted in the Republic of Ireland between 1991 and 1993 estimated that 65 quarries were occupied by Peregrines. There was a marked east/west gradient in occupancy with most occupied quarries in the east. Occupation of quarries by Peregrines is primarily influenced by cliff height.
Moore et al. (Tue,) studied this question.