Recent population change of the southern elephant seal at Iles Crozet and Iles Kerguelen: the end of the decrease?

Citation
C. Guinet et al., Recent population change of the southern elephant seal at Iles Crozet and Iles Kerguelen: the end of the decrease?, ANTARCT SCI, 11(2), 1999, pp. 193-197
Citations number
20
Categorie Soggetti
Multidisciplinary,Multidisciplinary
Journal title
ANTARCTIC SCIENCE
ISSN journal
09541020 → ACNP
Volume
11
Issue
2
Year of publication
1999
Pages
193 - 197
Database
ISI
SICI code
0954-1020(199906)11:2<193:RPCOTS>2.0.ZU;2-1
Abstract
The elephant seal populations breeding on the Iles Crozet and Kerguelen wer e regularly surveyed over the last three decades. At Iles Kerguelen the num ber of breeding females decreased at an annual rate of 3.6% between 1970 an d 1987, then increased at an annual rate of 1.1% to 1997. At Iles Crozet, t he population was reported to decrease at a rate of 5.35% between 1970 and 1990 but no change in numbers was found between 1990 and 1997. These result s indicate that the rapid decline observed both at Iles Crozet and Iles Ker guelen has ended, and these populations are now either stable or slightly i ncreasing. We suggest that broad scale change in environmental factors affe cting the food availability for elephant seals may be responsible for the c hange in numbers of these marine predators. The higher rate of decrease, th e longer period of decline, and the absence of any significant change betwe en 1990 and 1997 observed on the Iles Crozet may be explained by additional factors such as killer whale predation.