Dc. Lidgard et al., The status of breeding grey seals (Halichoerus grypus) on the east and south-east coasts of Ireland, MAMMALIA, 65(3), 2001, pp. 283-294
A two year survey was conducted to estimate the population status of grey s
eals on the east and south-cast coasts of Ireland and to document the types
of habitat used. Surveys were concentrated around the known breeding sites
of Lambay Island on the cast coast and the Great Saltee on the south-east
coast, during the breeding seasons of 1997 and 1998. The standard technique
of through-counting was used to estimate pup production and mortality. Pop
ulation estimates were calculated from the total pup production using the m
ultipliers given in the grey seal life-history table. The total grey seal p
up production was estimated at 41 and 49 for the cast coast group, and 100
and 128 for the south-east group in 1997 and 1998, respectively. The popula
tion estimate for the east coast group was between 172 and 221 and between
448 and 576 for the south-east group. Estimated pup mortality for the east
coast group was 7.3% and 2.0% and 3.0% and 8.6% for the south-east group in
1997 and 1998, respectively. Most pups were found on beaches, however data
from the Great Saltee suggests that beach-cave sites were the preferred ha
bitat early in the breeding season. This study has provided up-to-date info
rmation on an otherwise little studied marginal colony.