Investigating the biological diversity and ecological dynamics of oceanic fishery resources in the Andaman Sea, Indian Ocean

Abstract

Abstract This research paper investigates the oceanic fishery resources of the Andaman archipelago. The primary objective of this study is to gain a comprehensive understanding of the fishery and its dynamics including the environmental linkage surrounding these oceanic resources and to develop an effective strategy for sustainable exploration. Data were collected during an exploratory tuna long-line survey conducted between July 2022 and February 2023. The study documented a total of 13 species of fishes belonging to 11 genera, with tuna being the most abundant. Additionally, the study observed a significant increase in the population of pelagic stingrays, which nearly matched the number of hooked sharks (32). However, the hooking rates of sharks and bill fishes were observed to be gradually declining, resulting in a lower contribution to the overall species composition. One notable finding of the study was that site 11oN; 93oE (S4) exhibited the highest species diversity and potential. Furthermore, the aggregate hooking rates of fishes were particularly high between latitudes 11oN and 12oN. The study also analysed the seasonal distribution of each fish species and explored the correlation between environmental factors such as depth and temperature with species abundance and distribution. Statistical analysis indicates that there is no significant variation (p value = 0.20) between the environmental factors and the frequency of the species occurrence. Specifically, depth shows the highest correlation (r = 0.57) with the species distribution. In light of the diminishing hooking rate of oceanic fishery resources, the study puts forth several possible reasons and emphasizes the urgent need to implement conservation measures.

Keywords

• Tuna
• CPUE
• Diversity
• Hooking rate
• Redundancy analysis (RDA)