Movement of Black-capped Chickadees from Winter Area Toward Breeding Grounds Analyzed Through Banding Re-encounters
Bibliographic record
Abstract
In an earlier paper (Brooks 1987, Stewart 1988), I analyzed banding re-encounters of 14,396 Black-capped Chickadees (Parus atricapillus) reported to the Bird Banding Laboratory from 1922 to 1984.Only 13 re-encounters involved sameseason movement out of the 10-minute block of banding between 1 March and 15 June.I used the 1 March date as the probable onset of spring migration based on information presented by Lawrence (1958), Elder and Zimmerman (1983) Hussell and Stamp (1965) and Spelts (1963).Analysis of these 13 re-encounters shows that 11 individuals moved in an ENE, NE or NNE direction for distances ranging from 13 to 277 km in an elapsed time of 10 to 73 days.Two birds moved in a SSW and SE direction in 25 and 32 days for distances of 40 and 52 kin, respectively.Most studies indicate that chickadee populations remain relatively stable on wintering grounds (Butts 1931, Odum 1941, Wallace 1941, Lawrence 1958, McCamey 1962, Smith 1976, Loery and Nichols 1985).Destochefs et al. (1988) indicated that most chickadees remain in their breeding area for the winter season as long as food supplies are adequate.Loery and Nichols (1985) believed that chickadees are sitetenacious between 1 November and 1 March.Although Weise and Meyer (1979) indicated that perhaps 5-9% of all juveniles undergo permanent winter or spring dispersal movements, studies by Brittingham and Temple (1988) in Wisconsin indicated that permanent winter and spring dispersal movements rarely occur.Their studies and those by Destochefs et al. (1988) classified birds as dead if they were not present during winter on territories occupied before 1 November.Toward the end of winter, lower-ranked chickadees may undertake significant movement to seek out breeding territory but the extent and exact timing of that movement and the factors precipitating it are not well documented.Yunick (1982, pets.comm.)gives the date of earliest departure of chickadees from winter feeding grounds in the New York Adirondack region as 13 January.This date is based on his studies of the correlation between peak seed use and peak numbers of captures.In a report supportive of Yunick's 1980-81 observation, Charles R. Smith's report on Project Birdwatch indicated that in 1987 there was a 53% drop in chickadee populations at the feeders of project participants in NewYork State in mid-January.Desrochers et al.'s (1988) study of chickadees in Alberta indicated that winter flock breakup occurred between 20 February and 10 March in 1986 and 1987.I re-examined the 14,396 chickadee re-encounters (augmented by an additional 74 reported to the BBL between 1984 and 1986) and analyzed the direction, distance and duration of movement of chickadees banded between 13 January and 1 March and contrasted this with the same recapture information presented in my earlier paper.
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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".