Multivariate analysis of stable-isotope ratios to infer movements and utilization of estuarine organic matter by juvenile weakfish (<i>Cynoscion regalis</i>)
Bibliographic record
Abstract
Canonical discriminant analysis of the natural carbon, nitrogen, and sulfur stable isotopes in tissues of young weakfish (Cynoscion regalis) captured in Delaware Bay was used to infer movements of juveniles and to estimate the utilization of estuarine organic matter in this marine transient species. Two gradients emerged in the data. The first was associated with contributions from tidal salt marsh macrophytes, Spartina alterniflora in the polyhaline lower Bay and Phragmites australis in the brackish upper Bay. The second was associated with the expected change in phytoplankton carbon-isotope values along the salinity gradient in addition to the availability of macrophyte-derived organic matter within the Bay. The separation of the gradients reflected differences in the relative contribution of phytoplankton to weakfish secondary production in open waters versus marsh habitats. As they grew, discrepancies between the anticipated isotopic signatures of juvenile weakfish collected in a specific habitat and their actual signatures were interpreted as down-bay movements based on known life-history patterns. The size-specific differences in the isotopic signatures of weakfish suggested that stable-isotope data can be used to gauge the relative magnitude of marsh-derived organic matter exported from Delaware Bay via movements of juveniles out of the estuary.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot 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.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 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 teacher head, 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".