Assessment of Newfoundland and Labrador Snow Crab (Chionoectes opilio) in 2022
Bibliographic record
Abstract
The status of the Newfoundland and Labrador (NL) Snow Crab (Chionoecetes opilio) resource (Northwest Atlantic Fisheries Organization [NAFO] Divs. 2HJ3KLNOP4R) is assessed using a variety of metrics. The resource is assessed at larger-scale Assessment Divisions (ADs), which are comprised of combinations of NAFO Divisions or Subdivisions. Resource status was evaluated based on trends in survey exploitable (≥95 mm carapace width [CW] male Snow Crab) biomass indices, fishery catch per unit effort (CPUE), fishery recruitment prospects, and mortality indices. Information was derived from multiple sources: multispecies bottom trawl surveys conducted during fall in ADs 2HJ, 3K, and 3LNO Offshore and spring in AD 3Ps, two collaborative trap surveys covering all ADs, Fisheries and Oceans Canada (DFO) inshore trap surveys in ADs 3K, 3L Inshore, and 3Ps, fishery data from logbooks, landings from the dockside monitoring program, at-sea observer catch-effort data, and oceanographic surveys. Snow Crab landings remained near 50,000 t from 2007 to 2015, but steadily declined to a 25-year low of 26,400 t in 2019. Landings have continued to increase since then and were just under 50,000 t in 2022. Overall effort increased to near 3.4 million trap hauls in 2022. Overall standardized fishery CPUE was at a time-series low in 2018, but has increased to near the time-series high in 2022. The DFO trawl survey did not take place in 2022, therefore the trap survey time series was used to infer trends. The overall exploitable biomass index increased from historic lows in 2016–18 to near the long-term average in the past two years. The trap survey exploitable biomass index declined to a time-series low in 2017 and 2018, but has continued to increase since then. Fishery Exploitation Rate Indices (ERIs) were moderate to low in most ADs in recent years. Status quo removals would reduce or maintain the ERI in all ADs in 2023. Both pre-recruit (>75 mm CW adolescent males) catch indices and model predictions of exploitable biomass based on climate variables indicate that productivity for the next three to five years may remain similar to current levels. In 2023, all ADs are projected to be in the Healthy Zone of the Precautionary Approach (PA) Framework, except AD 2HJ, which is projected to be in the Cautious Zone. These projections assume status quo removals. Recent and ongoing data deficiencies resulted in the exclusion of AD 4R3Pn from the PA Framework.
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.002 | 0.002 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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".