Effect of climate change on habitat suitability and recruitment dynamics of swimming crabs in the Taiwan Strait

Abstract

Context Climate change reportedly affects global fisheries, including the highly valuable swimming crabs, an important benthic species in Asian waters. Aims The aim of this study was to determine the effects of El Niño–Southern Oscillation (ENSO) events on catch rates and habitat suitability of Portunus pelagicus, Portunus sanguinolentus and Charybdis feriatus in the Taiwan Strait. Methods We combined marine remote sensing data with Taiwanese trap vessel data to develop a weighted habitat suitability index modelling and analyse the recruitment dynamics of swimming crabs in different ENSO events. Key results Our results suggest that Increasing salinity (>33.5 PSU) and sea temperature (>18.6°C) during La Niña events had a positive effect on stock recruitment and habitat suitability index of P. pelagicus and C. feriatus. By contrast, P. sanguinolentus were not affected by ENSO events. The low catch rates for P. sanguinolentus in normal years and for C. feriatus and P. pelagicus in normal and El Niño years were highly consistent with the significant shrinkage of the habitat suitability index. Conclusions Monitoring climate change and environmental factors is essential for understanding their effects on marine ecosystems. Implications This research can help implement sustainable crab fisheries.