Not friends, just roommates: social organisation of two South American sea lion non-breeding colonies

GIARDINO, GISELA VANINA; MANDIOLA, MARÍA AGUSTINA; BASTIDA, JULIÁN; GANA, JOAQUÍN CARLOS MARIO; BASTIDA, RICARDO OSCAR; RODRÍGUEZ, DIEGO HORACIO

NEW ZEALAND JOURNAL OF MARINE AND FRESHWATER RESEARCH

RSNZ PUBLISHING

Año: 2022 p. 1 - 16

0028-8330

Groups of male South American sea lions (Otaria flavescens; SSLs)congregate in harbours on the northern coast of Argentina. Thesegroups are very dynamic, with a high degree of habituation tohuman activities and the ability to colonise different types ofartificial substrates, making them an interesting subject forunderstanding individual association patterns and spatiotemporalvariations in this species. In the present study, werecorded the associations between individual bleach-marked SSLsin the harbours of Mar del Plata (PM) and Puerto Quequén (PQ)on four different substrate types during four non-breedingseasons. We found that the association pattern differed betweenthe harbours, with a well-differentiated social structure beingevident in PM but very little social differentiation occurring in PQ.The observed social structure in PM may have resulted frompassive habitat preference rather than genuine social behaviour,as the association pattern disappeared when SSLs moved tosandy beaches within the harbour. Given that these colonies aremust-see tourist attractions but may have negative interactionswith human activities, we recommend considering the associationbetween SSLs and artificial habitats to design effectivemanagement strategies and reduce potential conflicts.