Figure 1

Macquarie Island southern elephant seal abundance trends (1951 – 2003) and the Southern Oscillation Index over that period. (Top panel) Abundance trends of the isthmus population of breeding females at Macquarie Island from 1951 to 2003. Two main census periods emerge (1) between 1951 and 1960 (the relatively high-density era) and (2) from 1993 to 1999 (the low-density era). (B) El Niño-Southern Oscillation (ENSO) conditions as measured by the Southern Oscillation Index (SOI) anomaly over the elephant seal foraging period from January to October between 1950 and 2001. High positive values of the SOI anomaly indicate El Niño conditions, and high negative values indicate La Niña conditions.