Effect of El Niño and La Niña on abundance of frugivorous and nectarivorous terrestrial birds in three tropical forests
Bibliographic record
Abstract
El Niño and La Niña climatic oscillations have dramatic effects on population dynamics and community structure of different animals. For marine birds, El Niño phenomenon drastically increases their mortality and reduces their reproductive success. In terrestrial ecosystems, the lack of long-term longitudinal data limits our understanding of the impact of El Niño and La Niña on bird populations and communities. We analyzed changes in abundance of frugivorous (large, medium, and small) and nectarivorous birds on three tropical forest types (lowland, premontane and montane) during El Niño, La Niña and neutral years using data from 16 Christmas’ Bird Counts in Costa Rica. Abundance of large and medium size frugivores increased during La Niña events, and the abundance of nectarivores during El Niño in the lowland forest, but neither of these events affected the abundance of small frugivores. In the montane forest, abundance of all four bird groups increased during El Niño, but decreased during La Niña events. Abundance of large, and small frugivores increased in the premontane forest during La Niña events, but other bird groups were not affected by La Niña. The abundance of small frugivores also increased during El Niño. We hypothesize that changes in abundance of frugivores and nectarivores during La Niña and El Niño events is probably correlated with fluctuations in food resources as it has been reported for other terrestrial tropical ecosystems.
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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 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 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".