Dispersion and site fidelity of breeding female grey seals (Halichoerus grypus) on North Rona, Scotland
Article first published online: 14 MAY 2009
1994 The Zoological Society of London
Journal of Zoology
Volume 233, Issue 3, pages 429–447, July 1994
How to Cite
Pomeroy, P. P., Anderson, S. S., Twiss, S. D. and McConnell, B. J. (1994), Dispersion and site fidelity of breeding female grey seals (Halichoerus grypus) on North Rona, Scotland. Journal of Zoology, 233: 429–447. doi: 10.1111/j.1469-7998.1994.tb05275.x
- Issue published online: 14 MAY 2009
- Article first published online: 14 MAY 2009
- (Accepted 4 August 1993)
Female grey seals (Halichoerus grypus) formed breeding aggregations on the island of North Rona, Scotland. Aggregations of females were associated particularly with gullies leading from the sea, leaving large areas of available space unoccupied. Changes in the degree of aggregation of females during the breeding season were similar in 1987, 1988 and 1989. Pronounced aggregations occurred in the early and late parts of each breeding season.
Of 67 breeding females marked in 1985, 62 (93%)) returned to N. Rona to breed in at least one season up to 1989, but 18 (27%) were present in all five years. Females came ashore up to 14 days before giving birth and 82% were observed first in the vicinity of their subsequent pupping site. Between 1985 and 1989, marked females which returned were faithful to their previous pupping sites, even when the previous pup had died. There was no evidence of a gradual change in the location of individual pupping sites over time. This pupping site fidelity may generate aggregations whose location, timing and composition is predictable.