MétaCan
Menu
Back to cohort
Record W2941183925 · doi:10.1093/jcbiol/ruz004

Evidence for a decline in the population density of Antarctic krill Euphausia superba Dana, 1850 still stands. A comment on Cox et al

2019· article· en· W2941183925 on OpenAlex

Why this work is in the frame

A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.

affAt least one author lists a Canadian institution in the pinned OpenAlex snapshot.

Bibliographic record

VenueJournal of Crustacean Biology · 2019
Typearticle
Languageen
FieldEnvironmental Science
TopicMarine and fisheries research
Canadian institutionsTula FoundationUniversity of British Columbia
FundersBritish Antarctic SurveyNatural Environment Research CouncilSight Research UK
KeywordsEuphausiaAntarctic krillKrillBiologyEuphausiaceaPopulationCrustaceanFisheryMarine conservationEcologyOceanographyDemography

Abstract

fetched live from OpenAlex

Antarctic krill (Euphausia superba Dana, 1850) exemplifies the key role of marine crustaceans in fisheries, foodwebs, and biogeochemical cycles. Ecological understanding and policy decisions require information on population trends. We have therefore worked with international colleagues to publish KRILLBASE, a database of fishery-independent krill population information for every decade since the 1970s. These data were used by Cox et al. (2018) who dispute the evidence for a late twentieth-century decline in krill density (number per unit area) in the Southwest Atlantic sector of the Southern Ocean and claim to overturn “much of recent thinking about climate-driven change in krill populations.” They support this claim with an analysis which reaffirms one non-significant result from an earlier paper but does not challenge the five significant results from that paper or those of other studies which support a decline. In this comment we examine the methods which led Cox and coauthors to conclude that krill density has been stable over the last 40 years. Although these authors provide a potentially useful approach, we show that their analysis was biased by the exclusion of usable net types, the inclusion of negatively biased data and down-weighting of high densities in the early part of the analysis period, the absence of recent data from the north of the sector, and a lack of statistical hypothesis testing. These factors maximise the chances of failure to detect a real decline. To aid future analyses we provide recommendations to supplement those which accompany KRILLBASE. We also suggest the need for consensus scientific advice on krill population dynamics based on agreed standards of evidence, evaluation of uncertainty, and a thorough understanding of the data. This will be more useful to policy makers and other stakeholders than polarised opinions. Meanwhile, the evidence for a decline in krill density still stands.

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.

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.002
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesnone
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Observational · Consensus signal: Observational
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.196
Threshold uncertainty score0.594

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0020.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.000
Bibliometrics0.0000.000
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0010.000

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.

Opus teacher head0.057
GPT teacher head0.349
Teacher spread0.292 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it