Bycatch risk of threatened and protected marine species in China’s seas and adjacent waters

Abstract

Large marine animals face severe threats from industrial fisheries globally, with bycatch recognized as a primary driver of population declines. This challenge is particularly pronounced in China’s seas and adjacent waters—a region of extraordinary biodiversity yet intense fishing pressure. Here we show a cumulative impact analysis framework, integrating information on species habitat suitability, and fishing effort stratified by gear type, to assess bycatch risks for threatened and protected species. Our results indicate that peak values of bycatch risk occur in the 23°N–25°N coastal waters of the Chinese mainland and off western Taiwan Island. On average, potential species bycatch occurred across 60% of their estimated ranges, and about 10% of the species may be bycaught in over 90% of their estimated ranges. Marine protected areas effectively mitigate risk, with internal bycatch risk one-third of that in surrounding areas. This study supports targeted conservation and fisheries management by prioritizing high-need species and sites. Bycatch risk in marine protected areas in the seas around China is one-third that of the surrounding area, showing they can effectively mitigate fishing pressures even with high bycatch risk along the continental shelf, according to a cumulative analysis framework integrating 10 years of data.