Developing a gillnet based abundance-at-age index for 4RSw Atlantic herring
Bibliographic record
Abstract
In 2021, a new experimental gillnet survey was started in Northwest Atlantic Fisheries Organization (NAFO) divisions 4Sw and 4R in collaboration with local harvesters, with the goal of developing a new index of spring and fall spawning Atlantic herring (Clupea harengus). This document outlines the survey design, proposes an analytical approach for estimating abundance-at-age indices, and provides an initial assessment of index quality. A new gillnet selectivity model was developed to convert observed length-specific catch rates across multiple mesh sizes into stock abundance-at-length, which was transformed into abundance-at-age using age-length keys. The resulting age compositions successfully tracked dominant cohorts, appeared robust against sample variability in space and time, and aligned with other independent data sources. While the indices appear promising for informing age composition, estimates of overall abundance remain uncertain in part due to limited time series lengths. Additional years of data will help with index validation and clarify its role in future assessments.
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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 | 0.003 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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".