Natal origin of black ducks harvested during the sport hunt in Québec, Canada
Bibliographic record
Abstract
ABSTRACT In Québec, Canada, the American black duck (Anas rubripes) breeds mainly in the boreal forest to the north, but a small segment of the population breeds in southern Québec in the densely populated agricultural areas surrounding the St. Lawrence River and Estuary. This agricultural breeding population faces increasing pressure from urbanization, competition with mallards (A. platyrhynchos), landuse changes, and hunting. In Québec, approximately 69% of black ducks are harvested in agricultural landscapes. Most birds harvested in Québec are taken in September, during the first 3 weeks of the hunting season, when birds breeding in the boreal habitat are unlikely to have initiated their southbound fall migration. This additional pressure on the agricultural breeding population could be detrimental to its long‐term sustainability. We measured carbon (δ13C), nitrogen (δ15N), hydrogen (δD), and sulfur (δ34S) isotopic compositions of feathers from hatching‐year black ducks of known natal origin (banded birds) and used these to develop a multivariate logistic regression classification model based on habitat type. We then applied this model to feathers from birds harvested in Québec during the fall sport hunt in those same years to determine their natal origin. Sixty percent in 2004 and 17% in 2005 of black ducks harvested during the fall sport hunt in Québec originated from the agricultural segment of the population, compared to 36% and 72% in those same years originating from the boreal area. This is in stark contrast to the species' distribution in Québec, with only approximately 4% of the population breeding in the agricultural portion of the province. Our results suggest that this harvest bias toward the agricultural segment of the breeding population, which may be accentuated in years when migration is delayed, could compromise its long‐term sustainability. We highlight the importance of existing regional survey programs, and the information gaps that exist concerning the natal origin of black ducks harvested in the northeastern United States, and the annual productivity of the agricultural black duck population in Québec. Stable isotopes from samples of known natal origin (banded birds) proved an effective tool to identify the natal origin of hunted birds. However, we caution against the use of published isotopic thresholds (δ13C, δ15N) to infer the origin of migrating organisms in small study areas. © 2014 The Wildlife Society.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot 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.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 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 source (direct Gemma or distilled Codex), 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".