The Xiamen Symposium on Marine Environmental Sciences (XMAS 2025)

Rastrelliger kanagurta is a commercially important pelagic fish caught in the southern SCS. Temperature changes may largely influence ocean circulations and processes that can affect the distribution and abundance of the fish. This study aims to determine the impact of sea surface temperature change on the seasonal distribution of R. kanagurta based on temperature projection from the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC) using maximum entropy (MaxEnt) base models. Fishery data from 2019 - 2023 and satellite data from MODIS-Aqua, chlorophyll-a (chl-a) and sea surface temperature (SST), were utilized. Results indicated that the constructed models applied with ‘good’ to ‘excellent’ predictive accuracy with SST optimal environmental range of 28.77°C to 31.33°C. The predictions of the potential fishing areas in EEZ off the East Coast of Peninsular Malaysia and northern West of Kalimantan revealed a reduction in the suitable fish habitats and northward habitat shift in response to the different degrees of warming under SST increase of 1.8°C, 2.6°C and 3.3°C except during southwest monsoon and intermediate monsoon in October under SST increase of 1.8°C. The temperature increase at 1.8°C during the southwest monsoon and intermediate monsoon in October resulted in the highest increase in the spatial extent and northward shift of the potential fishing areas in the Gulf of Thailand and Vietnam waters. The results demonstrated the pertinence of the approach in understanding the impact of SST rise in habitat suitability. This might form the premise for future fisheries resources management and forecasting.
 

Rastrelliger kanagurta, climate change, potential habitat, sea surface temperature increase, MaxEnt