Honeybees, like any other animal, need water to survive.
While the flowers produce nectar, the bees can obtain carbohydrates (sugar) and water out of the nectar itself. Nectar is a watery sweet liquid with sugar concentrations around 20% (water concentration could be from 35 to 85%).
When nectar is not available or the amount of water from the nectar is not enough, honey bees will have to forage for water to cover their needs.
Water foragers have a specific skill set since foraging for water is a little harder than foraging for nectar.
Bees will have to store the water in their crop (or honey sac or honey stomach). The crop is the first reservoir where liquids are stored and can be kept separated from the digestive system (by closing the proventricular valve).
To forage for water, the honey bee will have to take only enough honey/nectar from the hive to consume during transit and arriving at the water source with an almost empty crop. As she takes water in, any remaining sugar in the crop will be diluted. She now has to make it back to the hive, by consuming carbohydrates that are stored in her body, without being able to consume any calories from her water-filled crop.
Once she arrives at the hive, she needs to get in contact with other workers to pass the water to them, so she can empty her crop and take some honey/nectar to replenish her energy.
Honey bees need water to:
- cool down the brood area on hot days (evaporative cooling)
- increasing moisture in the brood area
- diluting stored honey for consumption
- making of royal jelly (about 67% water)
Honey bee brood is very sensitive to relative humidity levels. Optimum brood rearing requires 90 to 95% relative humidity (RH). If RH is below 50%, the eggs cannot eclode (emerge) and die after three days. With RH levels below 80% or above 95%, there is a significant drop in eclosion success (many eggs fail to dissolve their outer layer and turn into larvae).
As beekeepers, it’s very important to provide water sources for our own bees. Not only because it’s hard on the bees foraging for water, but also to prevent our backyard bees to bother neighbors.