A REVIEW OF ROOK STATUS, WITH NEW SOUTH PEMBROKESHIRE DATA, 1986 - 1996
Bibliographic record
Abstract
The rook population of southern Pembrokeshire was surveyed using nest counts during two breeding seasons, ten years apart (1986 and 1996). The results were compared over the study period, and analysed with reference to published data for this and other regions. The rookeries were non-randomly distributed, mainly on mixed farmland with limestone soils. Changes in the numbers of rook nests through time were variable within the study area, ranging from nest increases of over 30% in the south-west (Dale, Angle and Castlemartin), to decreases of 47% in the south-east of the county. The average size of rookeries was stable in the south, increased in the west, and decreased in the east. The overall size distribution of rookeries did not alter much between 1986 and 1996, and was similar to that seen in Pembrokeshire in 1975. The number of individual rookeries decreased by as much as 53%, except on the Castlemartin peninsula where an increase of 38% was noted. Overall, there was a slight decrease in total rook nest numbers of about 7% between the two south Pembrokeshire surveys. In contrast, at the national (UK) level, there were estimated increases of about 7% between 1975 and 1980. Subsequent national increases ranging from 5% to 14% were suggested by a combination of results of the Common Birds Census (CBC) and the Breeding Bird Survey (BBS), over the period 1986-1998. A national census in 1996 recorded an increase of about 40% (UK) and 36% (Wales) since 1975. Although parts of south Pembrokeshire have followed these national trends, the general trends there over the last 25 years have been declines between 1971 and 1975, and between 1986 and 1996, with an intervening period (1975-1980) of from 10 to 44% increase. South Pembrokeshire thus appears to be rather uncoupled from the UK trends in rook status, as has been noted for other common resident birds. The BBS report (1999) for the first time showed data between 1994-1998 separately for Wales and Scotland, and indicated a 7% decline in Welsh rooks and a 65% increase in Scotland. Bearing in mind the periods between previous full surveys (20 30 years), the strong regional variations, and the decline of many farmland species, it is recommended that more regular rook surveys be carried out at national level, and that local and regional surveys be better co-ordinated during intervening years.
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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 | 0.002 | 0.006 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.002 | 0.001 |
| Bibliometrics | 0.008 | 0.014 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
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".