Table 2.
Trends in honeybee phenology and yield in Wrocław, Poland, 1965–2010. Per annum changes in the variables (b) are displayed with SE. n indicates numbers of years of data
| n | Mean | b ± SE | R 2(%) | P | |
|---|---|---|---|---|---|
| First cleansing flight | 46 | 58 (Feb 27) | −0.25 ± 0.16 | 5.4 | 0.119 |
| First inspection of hives | 45 | 68 (Mar 9) | −0.11 ± 0.16 | 1.1 | 0.486 |
| First harvest | 45 | 151 (May 31) | −0.12 ± 0.11 | 6.6 | 0.297 |
| Last harvest | 39 | 206 (July 25) | 1.21 ± 0.27 | 35.0 | <0.001 |
| Interval from first to last harvest (days) | 39 | 51 | 1.22 ± 0.34 | 24.4 | 0.001 |
| Number of harvestsa | 45 | 3.0 | 0.015 ± 0.007 | 48.8 | 0.023 |
| Mean hive annual yield (kg) | 45 | 25.7 | 0.76 ± 0.10 | 55.1 | <0.001 |
| Mean hive annual yield UK | 40 | 19.8 | 0.58 ± 0.12 | 40.0 | <0.001 |
| Mean hive first harvest yield (kg) | 45 | 10.8 | 0.10 ± 0.06 | 5.0 | 0.138 |
| % of annual yield taken at first harvest | 45 | 47.8 | −0.91 ± 0.22 | 29.1 | <0.001 |
aPoisson regression, deviance R 2 reported