Ecologia e Fisiologia - Comunicações orais

Coral reefs retain the highest marine biodiversity and support a diverse array of fish species that interact in multiple ways. Among these species, damselfishes stand out as conspicuous reef fish, known for their territorial and aggressive behavior. These characteristics often lead to competitor dominance and a low probability of coexistence between damselfish species at the same place. However, the extent to which the territorial behavior of damselfishes influences patterns of agonistic interactions remains unknown. This study aims to fill this knowledge gap by investigating how the agonistic interactions within the Pomacentridae family happen at a global scale and which are the factors influencing these interactions to happen. To achieve this goal, we utilized a comprehensive global dataset, comprising eight sites representing a gradient of species richness and phylogenetic relatedness among fishes. In order to understand the factors underlying agonistic interactions, we employed a Path Analysis. Additionally, the out-degree centrality metric was used to assess the structure of agonistic interactions and identify the central species at each study site. The results revealed that the agonistic interactions of damselfishes were driven majorly by the species co-occurrence (Path Coefficient = 0.74) and secondly by their territorial behavior (PC = 0.07). Other tested variables, such as local richness (PC = 0.03) and maximum abundance (PC = -0.13) did not influence agonistic interactions. Among  damselfishes, those from the Stegastes genus played a central role in agonistic interaction networks across six out of eight study sites, which is associated with their territorial behavior and high frequency of interactions. This study significantly contributes to improving our knowledge of the relationship between co-occurrence and agonistic interactions, as well as understanding the structure of these interactions within the Pomacentridae family.