The annual monsoon trawl ban is helping the bottom-dwelling benthic fauna recoup significantly, say researchers.
As the benthic fauna is the chief food source of demersal fishery, the recoupment could better sustain fishery resources, according to a scientific paper published by the researchers of the Centre for Marine Living Resources and Ecology, Kochi.
The researchers reached the conclusion after assessing the outcome of four surveys on the bottom-dwelling fauna between 30 metre and 200 metre depth off Cape of Kanyakumari, Thiruvananthapuram and Kollam during the pre- and post-monsoon fishing holidays. The samples were collected as part of a research programme to assess the faunal standing stock and composition.
The analysis of benthic fauna revealed that their population recorded three- to four-fold increase during the trawl ban period, which coincides with the monsoon season, said K.U. Abdul Jaleel, the lead author of a research paper.
The study also revealed that polychaete worms, which constitute a major proportion of benthic fauna, also recorded an increase in species number during the period. The increase in fauna was found significantly supporting the demersal (the species that live in the bottom layer of water bodies) fishery. After the successful completion of the pilot study, plans are afoot to extend it to South Eastern Arabian Sea, between Kanyakumari and Goa, said M. Sudhakar, director of the Centre.
The fishing ban for mechanised trawling vessels is implemented for bringing down the fishing effort during peak spawning periods of commercially important species and to reduce stress on the benthic fauna. The ban period along the Kerala coast is between June 15 and July 31.
The “macro benthic standing stock showed considerable recoupment during the 45 day monsoon trawling ban (June–July) in the southern part of the south east Arabian Sea shelf, particularly between 30–50 m depths. A peak recruitment window for the dominant polychaete taxa in the region was identified around the onset and peak phases of the monsoon,” the authors write.
