'Increasing sea surface temperature results in prematuring of fishes'

Mamallapuram (Tamil Nadu) Oct 17 (IANS) Rising sea surface temperature (SST) is resulting in premature maturation of fishes at smaller sizes, reduced reproductive output, decreased recruitment to the fisheries and also affects fish distribution patterns in Indian waters, an official said on Tuesday.

In his address at the International Conclave on Mainstreaming Climate Change into International Fisheries Governance and Strengthening of Fisheries Management Measures in the Indo-Pacific Region here, Indian Council of Agricultural Research's (ICAR) Deputy Director General, Dr J.K. Jena said.

He also said the fishes which used to be near the surface are now found at deeper levels due to SST.

Jena said there is an extended distribution of commercially important fish species such as the Indian oil sardine and mackerel.

"These species are now found in regions where they were previously scarce, forming a local fishery which was hitherto unknown from those areas," he said.

Moreover, the increased SST affects the phenology of fish, leading to premature maturation at smaller sizes, reduced reproductive output, and decreased recruitment to the fishery.

Referring to India’s research initiatives for climate resilient marine fisheries, Jena said that the country has initiated a research project for the development of species distribution climate models and projections.

"These models are designed to predict alterations in sea temperature, ocean currents, and other climatic elements that influence fish populations. This scientific initiative aims to comprehend long-term patterns and develop appropriate strategies to safeguard the future of Indian fisheries," he said.

According to him, India has also launched climate smart marine fisheries value chain aimed at developing a prototype with critical control points to strengthen the value chain in the marine fisheries sector.

He also highlighted a concerning trend of Harmful Algal Bloom (HAB) events in the Indian Ocean region.

"A three-fold increase in HAB events has been reported in the Arabian Sea during the last two decades, with 31 events, compared to the first two decades with 10 events. Similarly, the Bay of Bengal has seen a two-fold increase in HAB events, with 14 events in the last two decades compared to just 6 events in the first two decades," he added.

In order to reduce the impact of the climate crisis, Jena suggested mariculture activities of climate-resilient species encouraging the cultivation of fish species that can thrive in changing environmental condtions.

“Use of potential fishing zones, integration of wind and solar energy in fishing vessels, enhancing preparedness of coastal population and sea ranching of depleted commercial species are some of the innovative solutions to address the climate crisis,” he said.

Vulnerability and pollution reduction investments would directly benefit six per cent of the total number of coastal populations of 250 million, National Centre for Sustainable Coastal Management's former Director, Dr R. Ramesh said.

"Indirect beneficiaries of this are estimated to be 77.19 million people of which 50 per cent are women," he said.

He also said that cutting-edge science and education are required to create awareness among the community on climate adaptation and mitigation. Upscaling skill development programmes for all coastal communities particularly women are also important.