Linking fish and crustacean taxonomic composition with seasonal contrasts in the soft-bottom intertidal zone

Abstract

The primary objective of this study was to investigate the seasonal fish and crustacean variations concerning taxonomic composition, species richness, and diversity in sandy beach habitat. For this purpose, we investigated the Sonmiani Hor lagoon area during four distinct seasons, i.e., northeast (NE) monsoon, pre-monsoon, south-west (SW) monsoon, and post-monsoon for one year. During each haul, the net was pulled about 100m along the beach in 0.5m depth. The results showed a strong linear correlation between the diversity index and equitability in fishes (r = 0.978). The diversity index was strong negatively correlated with the abundance and biomass (r = -0.978, -0.972, respectively). The physical attributes like sea surface water temperature and salinity showed a strong negative effect on species assemblages (r = -0.981 and -0.943, respectively). The mean air and water temperature illustrated approximately 3°C difference during NE and pre-monsoon seasons. However, salinity, pH, and electrical conductivity did not show any significant seasonal variabilities. Under the ecological indices, the fish species displayed higher diversity (H’ = 3.19) during SW monsoon, whereas the lowest diversity was observed during pre-monsoon (H’ = 1.58). The equitability and species richness, however, remained more noticeable during SW monsoon (J’ = 0.81). The total number of individuals of fish and crustaceans reached 4799 with 3813 fish individuals and 986 individuals of crustaceans. A total of 27 families of fish while five crustacean families comprising of 30 genera and 38 fish species while ten genera and 17 species of crustaceans were recorded. Liza subviridis displayed the highest abundance among the sampled fish species. In conclusion, fish species constituted a significant part of the coastal fauna in the study area. The seasonal variations displayed distinct variations in fish species composition and diversity.

Diversity of Penaeidae at the Mengkudu Bay Waters, North Sumatra, Indonesia

“…Krykhtina et al (2021) revealed temperature as a crucial environmental factor for the survival of aquatic organisms, particularly crustaceans, because this parameter affects their metabolism and reproduction processes. Additionally, climate can contribute to the survival of crustaceans due to their most abundant in waters during the rainy season (Wahyudin et al 2017;Hamid and Wardiatno 2018;Shields 2019;Gondal et al 2021;Muhtadi et al 2022). One of the diversity of crustaceans in the waters of Teluk Mengkudu is fishermen who sail at night using trawls which can damage coral reefs.…”

Seasonal analysis of food items and feeding habits of endangered riverine catfish Rita rita (Hamilton, 1822)

“…Changes in dietary preferences of a fish species largely depend on the availability of preferred prey items in the associated environment. An abundance of favorite prey items in the environment regulates their predominance of food items in the fish stomach (Palmeira and Monteiro-Neto, 2010;Gondal et al, 2020;Kim et al, 2021). Moreover, energy requirements by fish in a specific phase of life sometimes induce ontogenetic shifts in dietary mode and selectivity (Cruz Escalona and Abitia Cárdenas, 2004).…”