Intraspecific Nest Parasitism in the Savannah Sparrow
Bibliographic record
Abstract
Evidence of intraspecific nest parasitism in passetines is rare although some well documented cases do exist (Yom-Tov et al. 1974, Ibis 116: 87-90).This note describes an incident whose circumstances suggest that two complete clutches were laid simultaneously in the same nest by two female Savannah Sparrows (Passerculus sandwichensis ).On 23 June 1977 at La P•rouse Bay, Manitoba, 40 km east of Churchill, a Savannah Sparrow nest containing 10 eggs was discovered by flushing an incubating bird.Subsequently daily visits to the nest were made.On 1 July the nest contained six nestlings and four eggs and on the following day, nine nestlings and one egg.The status of the nest remained as such until 6 July when all contents of the nest were gone, presumably due to predation.With the exception of 3 July, weights and tarsal lengths were measured daily for all nestlings.The mean clutch size for 80 nests found locally in the same habitat in 1976 and 1977 was 4.74 -+ 0.55 (SD) (range = 3-6) eggs.Five was the modal clutch size.Peak clutch initiation date in 1977 was 16 June.Clutch initiation was highly synchronous with 79.4% of all clutches found in 1977 initiated between 14 and 18 June.The incubation period averaged 12 days with incubation usually beginning with the penultimate egg.
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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 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| 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 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".