This dissertation examines some important physiological and pheromonal factors regulating foraging and colony growth in honey bee colonies. The first study analyzed effects of soybean trypsin inhibitor (SBTI) on the development of hypopharyngeal gland, midgut enzyme activity and survival of the honey bee. In this study newly emerged caged bees were fed pollen diets containing three different concentrations of SBTI. Bees fed 1% SBTI had significantly reduced hypopharyngeal gland protein content. This study indicated that nurse bees fed a pollen diet containing at least 1% SBTI would be poor producers of larval food. In the second study nurse bee biosynthesis of brood food was manipulated using SBTI, and the resulting effects on pollen foraging were measured. Experimental colonies were given equal amounts of SBTI treated and untreated pollen. SBTI treatments had significantly lower hypopharyngeal gland protein content than controls. There was no significant difference in the ratio of pollen to non-pollen foragers and pollen load weights collected between the treatments. These results supported the pollen foraging effort predictions generated from the direct independent effects hypothesis. In the third study we tested whether brood pheromone (BP) regulated queen egg laying via modulation of worker-queen interactions and nurse bee rearing behaviors. This experiment had BP and control treatments. Queens in the BP treatment laid greater number of eggs, were fed for a greater amount of time and were less idle. Significantly more time was spent in cell cleaning by the bees in BP treatments. The results suggest that brood pheromone regulated queen egg-laying rate by modulating worker-queen interactions and nurse bee rearing behavior. The final study of this dissertation focused on how dose-dependent BP-mediated division of labor affected the partitioning of non-foraging and foraging work forces and the amount of brood reared. Triple cohort colonies were used and there were three treatments, Low BP, High BP and Control. Low BP treatments had significantly higher ratio of pollen to non-pollen foragers and greater pollen load weights. Low BP treatment bees foraged at a significantly younger age. This study has shown that BP elicits dose-dependent modulation of foraging and brood rearing behaviors.

This dissertation examines some important physiological and pheromonal factors regulating foraging and colony growth in honey bee colonies. The first study analyzed effects of soybean trypsin inhibitor (SBTI) on the development of hypopharyngeal gland, midgut enzyme activity and survival of the honey bee. In this study newly emerged caged bees were fed pollen diets containing three different concentrations of SBTI. Bees fed 1% SBTI had significantly reduced hypopharyngeal gland protein content. This study indicated that nurse bees fed a pollen diet containing at least 1% SBTI would be poor producers of larval food. In the second study nurse bee biosynthesis of brood food was manipulated using SBTI, and the resulting effects on pollen foraging were measured. Experimental colonies were given equal amounts of SBTI treated and untreated pollen. SBTI treatments had significantly lower hypopharyngeal gland protein content than controls. There was no significant difference in the ratio of pollen to non-pollen foragers and pollen load weights collected between the treatments. These results supported the pollen foraging effort predictions generated from the direct independent effects hypothesis. In the third study we tested whether brood pheromone (BP) regulated queen egg laying via modulation of worker-queen interactions and nurse bee rearing behaviors. This experiment had BP and control treatments. Queens in the BP treatment laid greater number of eggs, were fed for a greater amount of time and were less idle. Significantly more time was spent in cell cleaning by the bees in BP treatments. The results suggest that brood pheromone regulated queen egg-laying rate by modulating worker-queen interactions and nurse bee rearing behavior. The final study of this dissertation focused on how dose-dependent BP-mediated division of labor affected the partitioning of non-foraging and foraging work forces and the amount of brood reared. Triple cohort colonies were used and there were three treatments, Low BP, High BP and Control. Low BP treatments had significantly higher ratio of pollen to non-pollen foragers and greater pollen load weights. Low BP treatment bees foraged at a significantly younger age. This study has shown that BP elicits dose-dependent modulation of foraging and brood rearing behaviors.

Brood pheromone of the honey bee, (Apis mellifera) has been shown to elicit a wide array of primer and releaser effects on non‐foragers and foragers leading to the regulation of nursing, pollen foraging, and behavioral development such that the behavior of the colony may be regulated by the amount and condition of the larvae. To date, all studies into the effects of brood pheromone have either used uncharacterized whole extracts or a single blend of brood pheromone characterized from a population of honey bees in France. The variation in the relative proportions of the ten fatty‐acid ester components that characterize brood pheromone and some effects of this variation on pollen foraging and sucrose response thresholds were therefore observed. The objectives met in this dissertation were to determine whether changes in brood pheromone component proportions (blend) or amount communicates larval nutritional status and reports the results of observations of nurses and foragers in response to blends of brood pheromone from deprived and‐non deprived larvae, to measure how changes in brood pheromone blend changed pollen foraging behavior and if such changes could account for the pollen foraging differences between Africanized and European bees, and finally to observe the effects of exposure time on brood pheromone blend and to observe whether non‐foragers made contact with the pheromone. Brood pheromone was found to vary by larval rearing environment, but did not elicit the expected behaviors that would support a cue of nutritional status. Brood pheromone also varied significantly by mitochondrial lineage/population source and responses to brood pheromone appeared to be coadapted to blend, suggesting that brood pheromone may be important in race recognition. Finally, brood pheromone varied significantly over time and was found to be removed from sources by bees, suggesting possible mechanisms for loss of effect. Combined the results of this research indicate that brood pheromone blend differences lead to profound changes in colony behavior related to pollen foraging and food provisioning, providing novel tools for colony manipulation and mechanisms for understanding brood rearing division of labor and chemical communication.

This thesis examines three factors that may influence the change in protein content and size of the brood food glands in honey bees. Effects on the mandibular gland, involved in the production of brood food and in royal jelly, have not been examined in relation to primer pheromones while effects on the hypopharyngeal glands, also involved in the production of brood food, have not been examined in relation to queen mandibular pheromone. This thesis provides preliminary insight into how these pheromones affect the extractable protein content of brood food glands. The first study in this thesis assessed the effects of brood pheromone (BP), queen mandibular pheromone (QMP), and pollen presence on the protein content of hypopharyngeal and mandibular glands of the honey bee. In this study, newly emerged bees were caged for 12 days in one of eight treatments: Queenless state: 1) control (no pollen + no pheromone), 2) pollen, 3) BP, 4) BP + pollen; Queenright state: 1) QMP, 2) QMP + pollen, 3) BP + QMP, 4) BP + QMP + pollen. This study indicated that regardless of pheromone treatment, the most influential factor on gland protein content and size was pollen. The second experiment examined effects of varying pollen dilution on hypopharyngeal and mandibular gland protein content, bee mass, and lipid content of the honey bee. In this experiment, newly emerged bees were caged for 7 days and fed one of five treatments: pollen, 1:1 pollen: cellulose (vol:vol), 1:2 pollen: cellulose (vol:vol); 1:3 pollen: cellulose (vol:vol), and cellulose. This study indicated that bees on the pollen diet were significantly greater than all other diluted diets in measurements of hypopharyngeal gland protein content, lipid content, and mass with significantly less consumption. However, mandibular gland protein content of bees on the pollen diet was significantly greater only from pure cellulose.