Summary statistics for fishing effort per vessel flag as seen from AIS data.

Abbreviations: N, number of vessels; Cells, number of grid cells (0.01 decimal degrees) associated with fishing activity; Sum, the quantity of fishing hours per category; Mean, the arithmetic mean; sd, the standard deviation. Only the flag state category contains information on ‘Unknown flags’ (UNK).缩写说明：N表示船舶数量；Cells表示与捕捞活动相关的网格单元（0.01十进制度）数量；Sum指每一类别的捕捞总时长；Mean指算术平均值；sd指标准差。仅船旗国类别包含‘未知船旗（UNK）’相关信息。