West Coast of Scotland and Clyde Herring Fisheries Management Plan

Glossary

Maximum Sustainable Yield (MSY) – The largest long-term average catch that can be taken without impairing stock productivity

MSY proxy – Alternative indicator used where sufficient data are not available to estimate MSY directly

Stock - A population of a species that is managed as a unit.

Spawning Stock Biomass (SSB) – Total weight of mature fish capable of reproducing

Biological reference points – Thresholds (e.g. Btrigger, Blim) used to assess stock health

Category 3 stock (ICES) – Data-limited stock assessed using indicators rather than full analytical models

Total Allowable Catch (TAC) – Maximum catch that can be taken from a stock in a given period

Precautionary approach – Managing fisheries conservatively where uncertainty exists

Landing obligation – Requirement to land all catches of quota species

Bycatch – Non-target species caught during fishing

Directed fishery – Fishery that actively targets a specific stock

Ecosystem-based fisheries management (EBFM) – Management approach considering ecosystems rather than single stocks

Forage fish – Species that provide a key food source for predators

Predator–prey dynamics – Interactions between species affecting ecosystem balance

Climate-driven distribution shifts – Changes in species location due to warming seas

WoS herring – Herring stock in ICES Division 6aN and adjacent areas

Clyde herring stock – Locally managed stock confined to Clyde waters

Acoustic survey – Method used to estimate fish abundance using sonar

Stock mixing – Intermingling of fish from different populations