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Record W2142203972

Ecology and Demographics of Pacific Sand Lance, Ammodytes hexapterus Pallas, in Lower Cook Inlet, Alaska

2000· dissertation· en· W2142203972 on OpenAlexvenueno aff
Martin D. Robards, John F. Piatt

Bibliographic record

VenueLibrary and Archives Canada (Government of Canada) · 2000
Typedissertation
Languageen
FieldEnvironmental Science
TopicMarine and fisheries research
Canadian institutionsnot available
Fundersnot available
KeywordsSpawn (biology)InletIntertidal zoneBiologyFecundityJuvenilePopulationFisherySexual maturityEcologyGeographyOceanographyGeologyDemography
DOInot available

Abstract

fetched live from OpenAlex

Distinct sand lance populations occur within the relatively small geographic area of Lower Cook Inlet, Alaska. Marked meso-scale differences in abundance, growth, and mortality existed as a consequence of differing oceanographic regimes. Growth rate within populations (between years) was positively correlated with temperature. -- However, this did not extend to inter-population comparisons where differing growth rates were better correlated to marine productivity. Opaque otoliths form in juvenile sand lance during their first summer coinciding with their period of rapid growth. Subsequent opaque zones are deposited during spring, in conjunction with rapidly increasing water temperatures. Areal rather than radial descriptors of otolith size provide the best relation to sand lance length. A single linear regression was insufficient to describe this relationship with separate linear regressions needed for both juveniles and adults. No sexual dimorphism was observed for sand lance in length-at-weight (gonad-free) or length-at-age. Most sand lance reached maturity in their second year. Field observations and indices of maturity, gonad development, and ova-size distribution all indicated that sand lance spawn once each year. Males mature earlier in the season than females, but females (31 %) attain a higher gonadosomatic index than males (21 %). Sand lance spawned intertidally in late September and October on fine gravel/sandy beaches soon after the seasonal peak in water temperatures. Fecundity of females (93-199 mm) was proportional to length, ranging from 1,468 to 16,081 ova. Spawned eggs were 1.02 ± 0.08 mm in diameter, demersal, slightly adhesive, and deposited in the intertidal just below the waterline. Sand lance embryos developed over 67 days through periods of intertidal exposure and sub-freezing air temperatures. Mean dry-weight energy value of sand lance cycles seasonally, peaking in spring and early summer (20.91 klg-1 for males, 21.08 kJg-1 for females), and subsequently declining by about 25 % during late summer and fall (15.91 kJg-1 for males, 15.74 kJg-1 for females). Declines in energy density during late summer paralleled gonadal development, sand lance entering the winter with close to their minimum whole body energy content. Dry weight energy densities of juveniles increased from a minimum 16.67 kJg-1 to a maximum of 19.68 kJg-1 and are higher than adults in late summer.

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.

How this classification was reachedexpand

Full frame machine prediction

Teacher imitation

Not 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.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: metacan-v3-hybrid-931329e0061cValidation 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 score0.068
Threshold uncertainty score0.135

Distilled classifier scores by category (both heads)

CategoryCodexGemma
Metaresearch0.0000.000
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 head0.002
GPT teacher head0.148
Teacher spread0.146 · 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

Classification

machine, unvalidated

Machine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.

The models applied no category: nothing in the taxonomy fit this work.
Study designObservational
Domainnot available
GenreEmpirical

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".

Quick stats

Citations3
Published2000
Admission routes1
Has abstractyes

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