Colony state and regulation of pollen foraging in the honey bee, Apis mellifera L.

Abstract

To place social insect foraging behavior within an evolutionary context, it is necessary to establish relationships between individual foraging decisions and parameters influencing colony fitness. To address this problem, we examined interactions between individual foraging behavior and pollen storage levels in the honey bee, Apis mellifera L. Colonies responded to low pollen storage conditions by increasing pollen intake rates 54% relative to high pollen storage conditions, demonstrating a direct relationship between pollen storage levels and foraging effort. Approximately 80% of the difference in pollen intake rates was accounted for by variation in individual foraging effort, via changes in foraging activity and individual pollen load size. An additional 20% resulted from changes in the proportion of the foraging population collecting pollen. Under both high and low pollen storage treatments, colonies returned pollen storage levels to pre-experimental levels within 16 days, suggesting that honey bees regulate pollen storage levels around a homeostatic set point. We also found a direct relationship between pollen storage levels and colony brood production, demonstrating the potential for cumulative changes in individual foraging decisions to affect colony fitness.

Order, Disorder, Death: Lessons from a Superorganism

“…Stored pollen is consumed by nurse bees that convert it into the proteinaceous secretions of the hypopharyngeal glands (Crailsheim et al, 1992). Stored pollen inhibits pollen foraging, while pheromones produced by larvae (methyl palmitate, methyl stearate, methyl linoleate, methyl linolenate, methyl oleate, ethyl palmitate, ethyl stearate, ethyl linoleate, ethyl linolenate, and ethyl oleate) (Slessor et al, 2005) stimulate pollen foraging (Fewell and Winston, 1992;Pankiw et al, 1998). Colonies, therefore, regulate the amount of stored pollen probably through a combination of the inhibiting effects of pollen and stimulating effects of brood pheromone.…”

“…This regulatory scheme, per se, is put into operation by the workers that specialize on pollen collection. In response to accumulation of pollen in the nest and reduced pheromone signaling from brood, these foragers collect smaller pollen loads or stop foraging altogether (Fewell and Winston, 1992). Equilibrium pollen intake thus equals the pollen consumption that meets the protein demands of the developing larvae.…”

Weight of evidence evaluation of a network of adverse outcome pathways linking activation of the nicotinic acetylcholine receptor in honey bees to colony death

“…However, in addition to early onset of foraging, honey bee colonies have a repertoire of compensatory responses to overcome foraging deficiencies. These responses include increasing the activity of the existing (or remaining) foraging force, cannibalizing brood, and capping brood cells early (Fewell and Winston, 1992;Khoury et al, 2013;Schmickl and Crailsheim, 2001). These latter two adaptations serve to reduce the nutritional demands of the colony.…”

How a honey bee colony mustered additional labor for the task of pollen foraging

“…This adaptive plasticity in worker behavior is exemplified by the task of pollen foraging in honey bee (Apis mellifera L.) colonies: workers will adjust their pollen collection behavior, and thus the amount of pollen that is gathered, in relation to their colony's need for pollen (Fewell and Winston, 1992;Camazine, 1993;Fewell and Bertram, 1999). In nature, large fluctuations in a colony's pollen need are common; although a colony's consumption of pollen changes little from day to day, its collection of pollen can vary markedly as the weather changes (Seeley, 1995).…”

“…Numerous studies have demonstrated one or another of these processes (e.g., recruitment : Wilson, 1962;von Frisch, 1967;task switching: Gordon, 1989;Kühnholz and Seeley, 1997; raising work tempo: Waddington, 1990;Fewell and Winston, 1992). So far, however, no study has shown explicitly how all three processes can function together, or even if all three processes are employed simultaneously, when a colony must devote additional labor to a task.…”