Skip to main content

Stock Assessments

Photo: NOAA Fisheries

Mako Shark

Shortfin mako sharks (Isurus oxyrinchus) are found throughout the pelagic, tropical to temperate, North Pacific Ocean and based on genetic and tagging evidence, it is assumed to be a single stock across the North Pacific Ocean.

Shortfin mako sharks are a highly migratory species and one of the focal species of the International Scientific Committee for Tuna and Tuna-like Species (ISC) Shark Working Group (SHARKWG). The North Pacific stock is assessed by the SHARKWG which is a collaborative effort between scientists from ISC Member nations and observers to regularly evaluate the status of pelagic sharks that interact with international tuna and billfish fisheries in the North Pacific Ocean and provide scientific advice for conservation efforts.

The first full stock assessment of shortfin mako shark in the North Pacific Ocean was conducted in 2018. Prior to this assessment, an index-based approach was used to evaluate the status of the stock. Significant improvements to fishery and biological data availability allowed for the development of a length-based, age-structured assessment model in Stock Synthesis in 2018. That model incorporated time-series data of catch, catch-per-unit-effort, and sex-specific length-composition for fishing years 1975 to 2016.

Publications