Title : The importance of seasonal sea-surface height anomalies for foraging juvenile 1 southern elephant seals 2

26 A novel classification system was applied to the sea-level anomaly environment 27 around Marion Island. We classified the sea-level anomaly (SLA) seascape into 28 habitat types and calculated percentage of habitat use of ten juvenile southern 29 elephant seals (SES) from Marion Island. Movements were compared to SLA and 30 SLA slope values indicative of ocean eddy features. This classification provides a 31 measure of habitat change due to seasonal fluctuations in SLA. Some of the seals 32 made two migrations in different seasons, each of similar duration and proportion of 33 potential foraging behaviour. The seals in this study did not use any intense eddy 34 features but their behaviours varied with SLA class. Potential foraging behaviour was 35 positively influenced by negative SLA values (i.e., areas of below average sea-surface 36 height). Searching behaviour during the winter was more likely at eddy edges where 37 high SLA slope values correlated with low SLA values. Though the seals did not 38 forage within newly spawned eddies they did forage near the Sub-Antarctic Front 39 (SAF). Plankton and other biological resources transported by eddies formed at the 40 subtropical convergence zone (SCZ) are evidently concentrated in this region and 41 enhance the food chain there, forming a foraging ground for juvenile southern 42 elephant seals from Marion Island. 43 44 45