Abstract:
At-sea behaviour of central-place foraging fur seals and penguins in the Southern Ocean is
understudied during the latter stages of parental care and the subsequent pre-moulting period. This
biologically important period is costly to investigate due to the risk (or certainty) of losing tracking
instruments when the animals moult. Early in this period, parents must meet the increasing demands of
larger, more mobile offspring that are still nutritionally dependent and then the parents must recover lost
body condition prior to the onset of their annual moult. This study reports late-season, at-sea movement
patterns of macaroni penguins, chinstrap penguins and adult female Antarctic fur seals from the
subantarctic island Bouvetøya, in relation to remotely-sensed oceanographic features. Foraging trips
differing significantly in direction and distance travelled compared to those performed earlier in the
breeding season, coincide with the time when offspring would be expected to become independent. On
these trips, macaroni penguins moved towards the Polar Front while chinstrap penguins and Antarctic
fur seals moved southward. Individuals from all three species appeared to target submesoscale ocean
features once they were presumed to have been released from the constraints of feeding their young and
were able to travel greater distances from the colony.
