Abundance and distribution of Steller Sea Lions (Eumetopias jubatus) in British Columbia : Updates from 2016-17 aerial surveys
Notice bibliographique
Résumé
An aerial survey was conducted during the 2017 breeding season to assess trends in abundance and distribution of Steller Sea Lions (Eumetopias jubatus) in British Columbia (BC). This survey was part of a range-wide assessment of the Eastern population of Steller Sea Lions conducted to fulfill requirements under the Canadian Species at Risk Act and the United States (US) Endangered Species Act. Additional surveys were conducted in fall 2016 and winter 2017 to examine seasonal changes in abundance and distribution. A total of 31,753 (6,640 pup and 25,113 non-pup) Steller Sea Lions were counted during the breeding season survey. Models fit to the counts indicate a possible slowing in the annual rate of pup production since 2013, but not in the rate of growth in the non-pup component of the population. An estimate of the total population size was obtained by applying a correction factor of 1.48 to non-pup counts to account for animals that were at sea and missed during surveys. The adjusted 2017 breeding season population estimate was 43,200 (95% CI of 38,700 to 48,200) suggesting no significant change from the previous assessment. However, there continues to be an increase in the number of rookeries and year-round haulout sites being used by Steller Sea Lions in BC waters. There was evidence of five new major year-round haulout sites and two year-round haulouts were re-classified as rookery sites since 2013. Surveys conducted outside of the breeding season indicated a continuing trend of increased numbers of animals overwintering in BC waters from 2010–17. A total of ~31,400 animals were counted in October 2016, as compared to ~28,700 in fall 2012, while a total of ~22,400 animals were counted during surveys conducted in February 2017, as compared to the average of ~17,700 animals counted from multiple surveys flown during the winters of 2009-10. After applying a correction factor of 2.43 to account for animals that were at sea and missed during winter surveys, there were an estimated 52,700 (95% CI 41,000 to 67,800) Steller Sea Lions overwintering in the coastal waters of BC in 2017. Larger numbers of Steller Sea Lions estimated from winter surveys compared to breeding season surveys appear to be due to a net influx of animals from rookeries outside of BC. The Potential Biological Removal (PBR) for Steller Sea Lions during the summer breeding season is 2,474 for Canadian waters.
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 | 0,003 | 0,004 |
| Études des sciences et des technologies | 0,001 | 0,000 |
| Communication savante | 0,001 | 0,000 |
| Science ouverte | 0,001 | 0,001 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,003 | 0,001 |
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 ».