Reproduction of cavity-nesting birds in pesticide-sprayed apple orchards in southern Ontario, Canada, 1988–1994
Bibliographic record
Abstract
Abstract Egg fertility, clutch size andeggandchick survival and pesticideexposureof tree swallows (Tachycineta bicolor) and eastern bluebirds (Sialia sialis) were measured annually using nest boxes in sprayed and nonsprayed apple orchards in southern Ontario, Canada, during 1988–1994. Associations were examined between reproductive rates and historical organochlorine residues in eggs as well as the degree of exposure and toxicity of pesticides applied during the study period. Because many pesticides in current use are not persistent in wildlife tissues, a toxicity score was developed to describe the exposure for each nest. The toxicity score was calculated as the product of the extent of the orchard sprayed and the application rate of the chemicals, divided by an acute reproductive toxicity index of each chemical. Total organochlorine concentrations in tree swallow eggs were 0.74 to 3.47 μg/g, and in eastern bluebird eggs, these values ranged from 0.47 to 106.3 μg/g. More than 90% of the residue in eggs was pp′DDE. There was a significant increase in unhatched eggs in bluebirds as organochlorine levels increased in eggs. There were significant associations between toxicity scores of current-use pesticides and at least one avian reproductive parameter in every year of the study, but the reduction in reproductive rates associated with pesticides did not exceed 14%, for either species, in any year. Reduced reproduction occurred in 6 years in tree swallows but for bluebirds, this occurred in only 4 years.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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) | 0.027 | 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".