Pollen Collection and Pollen Foraging Behaviour of Honeybees (Apis mellifera) during Different Time Intervals from Brassica campestris L.

The pollen collection by honeybees (Apis mellifera Linguistica) from Brassica campestris was examined during February - March 2015 at National Agricultural Research Centre, Islamabad. Twenty five honeybee colonies were used which had similar number of worker bees, brood and stored food. In order to study the foraging activity of honeybees in the field condition, the number of pollen foragers returning to the hive entrance was recorded for 10 min duration on hourly basis between 0800 h to 1600 h for 3 days per week. The data was collected at 0800-1000 hours (early morning foraging activity), 1000-1200 hours (late morning foraging activity), 1200-1400 hours (Noon foraging activity) and 1400-1600 hours (afternoon foraging activity). The pollen collected in the pollen trap trays at regular intervals for a period of one month using pollen traps fitted at the entrance of the hives and left for a period of 8 h. The pollen loads were weighed fresh and preserved in the compact/air tight containers in the refrigerator. Our results showed maximum foraging ratio (59.88 ± 2.89) and pollen collection (145.8±8.79) during 1000-1200 hours followed by the duration of 1200-1400 hours when foraging ratio was 58.24 ± 3.03 and pollen collection was 134.4±5.49 and during 0800 - 1000 hours when foraging ratio was 48.36 ± 2.84 and pollen collection was 121.8±6.73, whereas, the lowest values were found during 1400-1600 hours when foraging ratio was 44.36 ± 3.36 and pollen collection was 117±3.77. It can be concluded that best time for pollen collection and foraging time for honeybee was 100-1200 hours. [ABSTRACT FROM AUTHOR]