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Fishing · Stock & sustainability · Stock

Legal-size biomass

Rebuilding

The stock assessment model’s estimate of fishable (legal-size) lobster biomass in your region — the abundance CPUE stands proxy for, and the base the total allowable catch is set from each year.

Worked example · Modelled biomass index · rebuilding
Regional abundance index 2021 2023 2026
Modelled biomass index · rebuilding
The benchmark

Modelled legal-size biomass, not raw catch rate, is the fishery’s most reliable abundance measure; east-coast rebuilding zones target 20% of unfished biomass, achieved or on track across several areas.

IMAS Tas Fisheries ↗
What it signals

Biomass is the number that ultimately governs your quota: as regional stocks rebuild toward their targets, catch limits and catch rates can rise. Following it region by region tells you where the fishery is strengthening and where rebuilding constraints will keep quota tight.

Data required to calculate
Assessment-area biomass estimatetUnfished biomass referencet

Silo pulls each of these from the sources the operation already uses, and keeps the figure current automatically.

How to improve it
01

Fish within regional limits so rebuilding stays on track.

02

Return berried and undersize animals carefully to aid recruitment.

03

Support fishery-independent surveys with accurate catch reporting.

Questions & answers

What is legal-size biomass?

The stock assessment model’s estimate of fishable (legal-size) lobster biomass in your region — the abundance CPUE stands proxy for, and the base the total allowable catch is set from each year.

What data do you need to calculate legal-size biomass?

You need: Assessment-area biomass estimate (t), Unfished biomass reference (t). Silo pulls each of these from the sources the operation already uses and keeps the figure current automatically.

What is a good legal-size biomass benchmark?

Modelled legal-size biomass, not raw catch rate, is the fishery’s most reliable abundance measure; east-coast rebuilding zones target 20% of unfished biomass, achieved or on track across several areas.

How do you improve legal-size biomass?

Fish within regional limits so rebuilding stays on track. Return berried and undersize animals carefully to aid recruitment. Support fishery-independent surveys with accurate catch reporting.

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