Blue sharks (BSH) are widely distributed throughout the temperate and tropical waters in the Pacific Ocean. The Working Groups on Sharks (SHARKWG) from the International Scientific Committee for Tuna and Tuna-like Species in the North Pacific Ocean (ISC) recognizes two stocks in the North and South Pacific, respectively, based on biological and fishery evidence. Relatively few BSH are encountered in the tropical equatorial waters separating the two stocks (ISC 2022).

Tagging data demonstrate long-distance movements and a high degree of mixing of BSH across the North Pacific Ocean. However, there is evidence of spatial and temporal structure by size and sex (ISC 2022).