Effects of Population Density on Survival in Merlins
Bibliographic record
Abstract
Abstract Accurate estimation of survival probabilities is an important component of population demographics, and it permits a test of the life-history prediction that densities influence population dynamics via suppression of survival rates. As part of a long-term study of urban-nesting Merlins (Falco columbarius), we estimated survival rates and tested for the effects of density dependence based on capture histories from 1,354 individuals (43 males and 110 females caught for the first time as adult breeding birds, and 597 males and 604 females caught for the first time as locally produced nestlings). Overall capture probabilities were 0.55 ± SD of 0.039 per year for adults, 0.10 ± 0.075 per year for juvenile males, and 0.58 ± 0.23 per year for juvenile females. Mean survival rate of adults was 0.62 ± 0.11 per year and did not differ significantly between males and females. Overall juvenile survival rates were 0.23 ± 0.032 for males and 0.055 ± 0.012 for females. Band returns suggest that the discrepancy in survival rates between juvenile males and females resulted from higher natal dispersal of females rather than from lower survival. Survival of adults (but not juveniles) was negatively density dependent, suggesting that density-dependent declines in survival exerted a regulatory effect on population size.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 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 teacher head, 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".