Growth and reproduction of the lake sturgeon (Acipenser fulvescens rafinesque) of the Nelson River in Manitoba
Notice bibliographique
Résumé
Depletion of Nelson River sturgeon through over-exploitation by the commercial fishery forced two closures of this fishery between 1921 and 1946. These failures prompted a program of biological research to determine rates of growth, reproduction and increments to stocks to provide a basis for the scientific management of this economically important species of fish. From 1953 to 1956 and 1959, 791 sturgeon were sampled from the commercial catch in the Sipiwesk Lake area of the Nelson River. Preliminary studies were conducted to determine the best method of age determination and back-calculation of growth. It was concluded that the best cross-sections of pectoral "spines", for purposes of age determination and back-calculation of growth, were located at the proximal end of the spine at the base of the swelling which forms the "knuckle"of the spine. The easiest and best measurement on this cross-section for back-calculation of growth was along the radius of the spine from the centre of ossification to the posterior edge of the spine, along the acute angles formed by the annuli in this area. The relationship between fork length (x) and the average radius of the pectoral spine (y) as determined by the method of least squares was: x = .14y + 2.2. In the calculation of size at any previous age, best results were obtained by back-calculating along a line which converged with the intercept. The best representation of growth in Nelson River sturgeon was obtained by cumulatively totalling the average annual calculated increments of growth for a number of specimens. It is readily apparent that female lake sturgeon of the Nelson River grows faster and lives much longer than the male. The average annual Depletion of Nelson River sturgeon through over-exploitation by the commercial fishery forced two closures of this fishery between 1921 and 1946. These failures prompted a program of biological research to determine rates of growth, reproduction and increments to stocks to provide a basis for the scientific management of this economically important species of fish. From 1953 to 1956 and 1959, 791 sturgeon were sampled from the commercial catch in the Sipiwesk Lake area of the Nelson River. Preliminary studies were conducted to determine the best method of age determination and back-calculation of growth. It was concluded that the best cross-sections of pectoral "spines", for purposes of age determination and back-calculation of growth, were located at the proximal end of the spine at the base of the swelling which forms the "knuckle"of the spine. The easiest and best measurement on this cross-section for back-calculation of growth was along the radius of the spine from the centre of ossification to the posterior edge of the spine, along the acute angles formed by the annuli in this area. The relationship between fork length (x) and the average radius of the pectoral spine (y) as determined by the method of least squares was: x = .14y + 2.2. In the calculation of size at any previous age, best results were obtained by back-calculating along a line which converged with the intercept. The best representation of growth in Nelson River sturgeon was obtained by cumulatively totalling the average annual calculated increments of growth for a number of specimens. It is readily apparent that female lake sturgeon of the Nelson River grows faster and lives much longer than the male. The average annual Recommendations for the management of future fisheries on the Nelson River and other areas are given. These pertain to production limits, fishing seasons and the minimum legal size of fish and fishing gear.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction machine sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Le volet Gemma est une étiquette directe du modèle pour chaque travail de la base, lue sur la notice réduite au titre. Le volet Codex est un classifieur appris des 10 348 étiquettes directes de Codex et calibré sur les taux pondérés de l'échantillon; les champs sans appui suffisant ne portent aucun appel Codex. Le mode candidate est l'union des deux volets; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont pas des étiquettes humaines.
Scores du classifieur distillé par catégorie (deux têtes)
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,001 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,001 | 0,001 |
| Études des sciences et des technologies | 0,001 | 0,001 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,001 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule source (Gemma direct ou Codex distillé), pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».