Extending the Northern Cod (Gadus morhua) assessment model - part III : revisiting the Limit Reference Point
Bibliographic record
Abstract
Under the Canadian Precautionary Approach (PA) to fisheries management, a Limit Reference Point (LRP) is defined as the stock status below which serious harm is occurring. Since 2010, the LRP for Northern cod has been defined as the average spawning stock biomass (SSB) from the 1980s as this was the last time medium levels of recruitment were observed. This definition has been formally revisited using the Beverton-Holt stock-recruitment relationship by calculating the level of SSB that produces 50% of maximum predicted recruitment. Potential maximum sustainable yield (MSY) based alternatives are also considered and the limitations of both recruitment-based and MSY-based reference points are discussed in this perspective piece. In short, the suitability of an MSY-based LRP is called into question for Northern cod as estimates are sensitive to changes in vital rates and fisheries selectivity, both of which have exhibited substantive changes through time since 1954. I suggest that estimates of MSY may be more suitable for the provision of tactical, ecosystem-informed advice. Ultimately, continued use of the recruitment-based LRP is recommended since it should be above the point at which recruitment rates are impaired and depensation or extirpation is a concern.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.002 | 0.001 |
| Open science | 0.002 | 0.002 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".