Brood Pheromones

1 . What is brood pheromone and what does it do?

The brood itself produces a “brood ester pheromone” (BEP). When brood is present, workers gather pollen. When brood is not present, their pollen foraging activity is greatly reduced. It is the brood ester pheromone that is responsible for this behavior.

2 . How do the brood communicate their needs to the nurse bees?

The esters are present in amounts in proportion to larval age. Nurse bees can detect the differing proportion of esters at any time in BEP. Nurse bees can recognize the needs of larvae by the differing proportion of esters and provide them with optimal resources needed at any time. Thus, the larvae communicate with the nurse bees through BEP what their immediate needs are, and the nurse bees can respond appropriately to those needs.

3 . What are some of the other effects of brood ester pheromone?

Four of the esters, produced by the brood, in the proper amount and combination induce the nurse bees to cap the cell. These esters are produced in large quantities when the larvae begin their cocoon spinning activity. Various amounts of esters produced by brood also enhance the amount of royal jelly deposited in the cell. Brood pheromone also inhibits the ovaries in worker bees. Brood pheromone also helps control the resources brought into the colony. When the young larvae need more resources (food etc.) they emit a large amount of an ester (ocimeme) that promotes worker bee foraging. When the larvae are older and have a higher need for the attention of nurse bees, they admit a higher level of BEP which keeps nurse bees in contact with them for a longer time. What an amazing feedback loop!

4 . What happens when brood is transferred from one colony to another?

Brood transferred from one hive to another is readily accepted, when worker transfer may not be accepted. It is possible that brood pheromone masks colony odor.

5 . What is “comb pheromone” and what does it do?

The comb emits an odor that bees perceive. Brood survives best in older comb, suggesting that old comb sequesters brood pheromone. When colonies are offered empty drawn comb they store a greater amount of food stores.