Schilds A. auteur aut IRD Mourier Johann auteur aut IRD Huveneers C. auteur aut IRD Nazimi L. auteur aut IRD Fox A. auteur aut IRD Leu S. T. auteur aut IRD text journalArticle eng text/pdf born digital access Groups or aggregations of animals can result from individuals being attracted to a common resource or because of synchronised patterns of daily or seasonal activity. Although mostly solitary throughout its distribution, white sharks (Carcharodon carcharias) seasonally aggregate at a number of sites worldwide to feed on calorie-rich pinnipeds. At the Neptune Islands, South Australia, large numbers of white sharks can be sighted throughout the year, including during periods of low seal abundance. We use a combination of photo-identification and network analysis based on co-occurrence of individuals visiting the site on the same day to elucidate the population structure and aggregatory behaviour of Australia's largest aggregation of sub-adult and adult white sharks. We photo-identified 282 sharks (183 males, 97 females, 2 unknown) over a 4.5-year period (June 2010-November 2014) and found that white sharks did not randomly co-occur with their conspecifics, but formed four distinct communities. Tendency to co-occur varied across months with males co-occurring with more individuals than females. Sex-dependent patterns of visitation at the Neptune Islands and resulting intraspecific competition likely drive the observed community structure and temporal variability in co-occurrences. This study provides new insights into the aggregatory behaviour of white sharks at a seal colony and shows for the first time that white shark co-occurrence can be non-random. specialized Social network analysis Gregariousness Social behaviour Aggregation Photo-ID Carcharodon carcharias AUSTRALIE NEPTUNE ILES 034 020 73 10 art. 138 [12 p.] 2019 0340-5443 https://www.documentation.ird.fr/hor/fdi:010077094 10.1007/s00265-019-2745-1 0340-5443 [F B010077094] https://www.documentation.ird.fr/hor/fdi:010077094 https://www.documentation.ird.fr/intranet/publi/2019/10/010077094.pdf Accès réservé (Intranet de l'IRD) IRD - Base Horizon / Pleins textes 2019-11-05 2025-02-24 fdi:010077094 fre