Effect of Queenlessness on Worker Survival, Honey Gain and Defence Behaviour in Honeybees
SummaryThe effects of queenlessness on worker honeybees (Apis mellifera?) were tested with 50 colonies in groups of 10 (five treatments and two replicates) in August, October and December, 1984 and February and April, 1985 in Baton Rouge, Louisiana. The 10 colonies in each group were all from a single heterogeneous mixture of bees, and each colony began with about 6000 workers and no brood. The five treatments each lasted for 28 days and consisted of (1) caged queen for 28 days, queenless for 0 days; (2) caged queen for 21 days, queenless for 7 days; (3) caged queen for 14 days, queenless for 14 days; (4) caged queen for 7 days, queenless for 21 days and (5) caged queen for 9 days, laying queen for 19 days (control). With prolonged queenlessness worker survival, colony weight gain and defence behaviour (number of stings) decreased. Queenlessness did not induce drifting.
The drifting of honey-bees
1. Most of the bees which drift do so during their orientation flights and before they become regular foragers. 2. Bees emerging in August and September drift less than those emerging earlier in the year. 3. Drifting varies considerably in different circumstances, and may be extensive. 4. Drones drift two to three times as frequently as workers. 5. An individual bee is more likely to drift from a small to a large colony than vice versa, but the greater number of bees flying from the large colonies may result in a net gain in bees by the smaller ones. 6. When hives are arranged in repetitive patterns, bees drift to hives occupying similar positions in the pattern to their own. When hives are arranged in rows, bees from the centre colonies drift more than those at the end, resulting in the latter colonies gaining numerically. In some circumstances, more bees drift to hives in one direction than in the opposite direction. 7. Facing hives in different directions and painting them different colours considerably reduces drifting, the facing of hives in different directions being of the greater significance.
Investigations on the rôle of organic matter in plant nutrition
1. As the result of decomposition of green manure in a swamp soil, the coarse fractions (including coarse and fine sand) of the surface layer (first 3 inches) decreased by 11·2 per cent. while the fine ones (silt+clay) increased by 9·8 per cent. in the course of 43 days. The effect was less pronounced in the manured soil maintained at 60 per cent. saturation, while no alteration was to be noticed in the case of the unmanured specimens. 2. Treatment with dilute hydrochloric acid prior to dispersion had no appreciable effect on the estimates of mechanical composition obtained in the different cases. Loss in solution was also comparatively small. 3. The silica-sesquioxide ratio increased slightly as the result of decomposition of green manure in swamp soil. The composition of the fine fractions was also altered, the total percentages of the oxides of iron, aluminium and silicon increasing from 90·5 to 99·3 in the course of 71 days. 4. The practical significance of the above and related observations has been discussed.