Stable-isotope ratios of blood components from captive northern fur seals (<i>Callorhinus ursinus</i>) and their diet: applications for studying the foraging ecology of wild otariids
Bibliographic record
Abstract
Stable nitrogen and carbon isotope ratios ( 13 C/ 12 C and 15 N/ 14 N, respectively) of plasma, serum, clotted red blood cells, and unclotted red blood cells from six captive northern fur seals (Callorhinus ursinus) and two fish species in their diet, Atlantic herring (Clupea harengus) and Icelandic capelin (Mallotus villosus), were measured. The δ 15 N values from the fur seal blood components ranged from 15.5 ± 0.1 (mean ± SE; all RBCs) to 16.7 ± 0.1 (plasma), and δ 13 C values ranged from 18.3 ± 0.1 (serum) to 17.5 ± 0.1 (clotted RBCs). Fur seal blood components had higher δ 15 N and δ 13 C values than their diet. Mean enrichments of 15 N between fur seal RBCs and plasma/serum and their prey were +4.1 and +5.2, respectively, while mean 13 C enrichments were +0.6 (serum), +1.0 (plasma), and +1.3 to +1.4 (all RBCs). Fur seal blood components did not differ in δ 15 N or δ 13 C between the sexes. One female (Baabs) was pregnant at the time of sampling and was resampled 4 months later, when she was approximately 3 months post parturient. The δ 15 N values of the blood components taken from Baabs during pregnancy were all higher by 0.6 (unclotted RBCs) to 1.3 (plasma) than those of samples taken during lactation, while her δ 13 C values were nearly the same (RBCs) for the two time periods or lower during lactation by 0.5 (serum) and 0.7 (plasma). This study was the first to analyze isotope ratios of blood components from captive fur seals and their prey. The subsequent establishment of fractionation values between captive fur seals and their diet can be used to interpret trophic level and habitat usage of otariids feeding in the wild.
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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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| 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) | 0.001 | 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 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".