Abstract
Foraging behavior and life span in individual honey bees, Apis mellifera L. were examined. I investigated the genotypic effects on these important parameters using bees derived from a two-way colony-level selection program for high and low pollen hoarding behavior. I also studied the effects of juvenile hormone (JH) on foraging preferences (nectar or pollen) and on nectar foraging performance.In an environmentally controlled flight room, I trained bees of known age from the high and low pollen strains to a feeder containing 50% (weight solute/weight solution) sugar solution or a dish of ground pollen. I quantified the amount of sugar solution (nectar) the bees loaded per trip as well as the rate of visits (foraging rate) to nectar or pollen feeders throughout the individuals' foraging careers. I also measured the age of each bee on her first foraging trip (initial foraging age) and the adult life span of each individual.Individuals changed their nectar load sizes and foraging rates during their lifetime. Generally, they increased their nectar load sizes and foraging rates for about a week, maintained about the same level for several days, followed by a drop in both parameters. The individuals' genotypes explained some of the variation in foraging rate for nectar and pollen. The low pollen strain bees made more nectar trips per hour than did the high pollen strain bees, and the high pollen strain bees took more pollen collection trips per hour than did the low pollen strain bees. Also, the low pollen strain bees initiated foraging earlier in life and had shorter life spans than did the high pollen strain bees, when foraging for either nectar or pollen. Within each pollen strain, bees that started foraging earlier tended to forage more days. This result suggests a trade-off between in-hive tasks and foraging.I tested the possible effects of JH on the foraging preferences for nectar or pollen, and on foraging performance by applying the JH analogue, methoprene, on foragers. I found that methoprene had no effect on foraging preferences, nectar load size, foraging rate, and foraging span.