Lunar cycle drives family-specific larval fish assemblages in the tropical nearshore ecosystem

Abstract

Responses to lunar cycles vary amongst taxonomically distinct marine creatures. We calculated larval fish diversity and density over four successive lunar phases: new, first quarter, third quarter, and full. A bongo net with a mesh size of 300µm mesh size from a tropical nearshore water of the Straits of Malacca, Malaysia. We collected 5,305 fish larvae from 27 different families. Diversity indices for richness (Shannon-Wiener, H), dominance (Simpson, D) and evenness (Pielou, E) decreased from the full lunar phase onwards. Larval density, on the other hand, was much higher during the new lunar phase. We also determined that the larval fish family was either selectively present during each lunar phase or had a peak density during full and new moons. The larval fish assemblages revealed a preference for spawning events during the lunar phases. Human activities in the vicinity area are advised to be minimised during this period to mitigate harmful influence on larval fish recruitment in the nearshore area.