Seasonal variability in fish market composition show multi-driver controls on seafood supply in Singapore

Wet markets serve as important retail hubs for seafood across Southeast Asia, providing valuable insights into regional fisheries dynamics. However, knowledge of the specific drivers shaping fisheries dynamics remains limited. We assessed marine fish abundance and taxonomic richness at Tekka Market in Singapore over a 12-month period, from August 2024 to July 2025. Our surveys recorded 181,604 individual fishes across 215 taxonomic groups, revealing clear seasonal fluctuations in abundance and richness, peaking in September and July, respectively. The domestic trade was dominated by pelagic species, such as trevallies and anchovies, and a smaller number of uncommon and globally threatened fishes. Focusing on three case studies, our findings revealed distinct mechanisms driving these fluctuations. The abundance of Bombay Duck ( Harpadon nehereus ) increased from July to September, potentially related to the species’ spawning migrations. There was also a positive relationship between anchovy (family Engraulidae) abundance and temperature, with warmer waters associated with higher market availabilities. Our study further revealed that significantly higher numbers of rabbitfishes (family Siganidae) were sold during the Lunar New Year compared to the non-holidays, driven by cultural beliefs of good luck. These results demonstrate that the market supply of marine fishes in Singapore is influenced by a complex interplay of biological, environmental, and socio-cultural factors. Given Singapore’s heavy reliance on regional imports to meet domestic demand, these dynamic fluctuations expose inherent vulnerabilities within the supply chain that may threaten local food systems. Consequently, long-term market monitoring is vital to anticipate potential supply disruptions and safeguard national food security.