Journal of the Marine Biological Association of India

Co-occurrences of jellyfish in the shrimp fishing grounds of Palk Bay and the Gulf of Mannar and their implications in the commercial fishery

Volume 68 Issue 1

M. Rajkumar, S. Thirumalaiselvan, R. Saravanan, K. Shanmuganathan, A. K. Abdul Nazar and Shoba Joe Kizhakudan

doi:10.6024/jmbai.2026.68.1.2680-10

Abstract

The regular abundance of jellyfish in Palk Bay and the Gulf of Mannar during the Indian summer was studied in 2023. Experimental bottom trawling was carried out to assess the influence of jellyfish on fish and shrimp catches in the shrimp fishing grounds of the Gulf of Mannar and Palk Bay. The jellyfish that were caught in the gear were measured and quantified. Among fin fishes, about seven species of silverbellies were more prevalent in both regions’ catches. In Palk Bay, Lobonemoides robustus is a common jellyfish, whereas three other jellyfish species were also found in the Gulf of Mannar, including Cyanea nozakii, Rhopilema hispidum, and Chrysaora chinensis. C. nozakii was shown to be the dominant and most numerous species in the Gulf of Mannar region. Using morphometric data, the relationship between bell diameter and weight for these jellyfish was determined. In general, the perception of fishermen is that there is less fish catch in the jellyfish areas, but in our experiment, the shrimp catch was normal despite the jellyfish abundance. Continuous monitoring can help to demarcate jellyfish occurrence areas as Jellyfish Focal Areas (JFA) for better management of commercial fishing operations in both the Gulf of Mannar and Palk Bay.

Keywords

Jellyfish focal areas, shrimp fishery, bottom trawl, catch rate

Date : 25-05-2026