SEX DIFFERENCES IN NEST VISITATION BY CHICK-REARING MARBLED MURRELETS
Bibliographic record
Abstract
We report a significant male bias in dawn and dusk nest visitations of breeding, radio-marked Marbled Murrelets (Brachyramphus marmoratus) during the chick rearing period in Desolation Sound, British Columbia, Canada, from 1998–2000. Overall visitation rates of males during chick rearing were 1.3 times greater than those of females. Dusk visitation rates by males with active nests were 1.8 times greater than those of females. Male visitation rates were similar between early and late chick rearing, both within and among individuals. However, female visitation rates during late chick rearing were significantly lower than female rates early in rearing, both within and between individuals. In addition, between-sex comparisons of nest visitation during early and late chick rearing showed significant reductions in female effort relative to males, only during late chick rearing. These results suggest that male birds may provision chicks more often than females, especially during the last half of chick rearing. These findings offer a behavioral explanation for the annual male bias of birds flying inland during the chick rearing period at Theodosia Inlet in Desolation Sound from 1994–1999. Although female-biased provisioning has been documented in several species, male-biased provisioning has not been widely reported in other alcids. Diferencias de Sexo en la las Visitas al Nido en Brachyramphus marmoratus durante la Crianza de Pichones Resumen. Presentamos evidencia sobre un sesgo hacia los machos en las visitas a nidos efectuadas al amanecer y el crepúsculo durante la crianza de pichones, en individuos marcados con radios en Desolation Sound, Columbia Británica, Canadá, entre 1998–2000. La tasa de visitas de los machos fue 1.3 veces mayor que la de las hembras. La tasa de visitas de los machos al crepúsculo con nidos activos fue 1.8 veces mayor que las hembras. La tasa de visitas de los machos fue constante a través del período de crianza, tanto para un mismo individuo como entre individuos. Sin embargo, la tasa de visitas de las hembras fue significativamente menor al final que al inicio de la crianza, tanto para un mismo individuo como entre individuos. Además, la tasa de visitas de las hembras fue menor que la de los machos al final de la crianza. Estos resultados sugieren que los machos abastecen a los pichones en mayor medida que las hembras, especialmente en la última parte de la crianza. Asimismo, los resultados ofrecen una explicación conductual para la dominancia anual de machos volando tierra adentro durante la crianza en Theodosia Inlet, Desolation Sound, entre 1994–1999. En pocas ocasiones se ha descripto abastecimiento paternal en los álcidos, donde principalmente las hembras se encargan del abastecimiento.
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) | 0.006 | 0.003 |
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; both teacher heads agree on what is shown here.
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".