Figure 1.

The general nature of the relationship between first-year survival (open squares) and the SOI (solid diamonds) recorded during January–October for each year of the first foraging trip for the seven cohorts (1993–1999) of southern elephant seals at Macquarie Island. The figure shows that survival is highest during ENSO events, i.e when the SOI is lowest. However, we recognize that the time-series is relatively short, making rigorous time-series analysis difficult. Nevertheless, even when we take account of the temporal autocorrelation within the two time-series and calculate the effective degrees of freedom (Pyper & Peterman 1998), the strong correlation coefficient (r=−0.868) remains robust (p=0.05). The data labels associated with the survival curve represent cohort membership for the seven seal cohorts we studied.