Spatial-temporal variation of marine fishing activities responding to policy and social events in China.

The spatial-temporal variation of the impact of political and social factors such as (Fishing Moratorium, Marine Protected Areas, New Year, and COVID-19) on fishing activities offshore was evaluated based on fishing efforts data by AIS from 2013 to 2020 for China. It is found that the maximum fishing intensity occurs within 20-30 km of the coastline, the area within 40 km of the coastline covers 51% of fishing activities, and within 100 km of the coastline accounts for 92% of fishing activities. From 2013 to 2016, fishing hotspots showed a highly aggregated spread in the Bohai Sea and the East China Sea. Since 2017, China's hot fishing areas have gradually fragmented and southern moved. During the fishing moratorium, the fishing efforts decreased by 51% compared to the pre-moratorium, and after the moratorium, the fishing efforts increased by 81% compared to the pre-moratorium on average. We investigated fishing activities in and around 249 MPAs in China and found that 71% of MPAs are free of fishing, and average fishing intensity across MPAs is 35% lower than not protected areas. Regarding the social events, it is concluded that during the New Year holiday, the fishing efforts and fishing area were reduced by 79% and 73%, respectively, compared to the regular fishing period. The COVID-19 epidemic prompted a decrease in fishing efforts in 2020 for the first time since 2013, with the average fishing efforts in 2020 being 14% and 6% lower than in 2019 and 2017 to 2019, respectively.