Pollen availability determines how bees’ life will unfold
“Colony population responds to pollen availability”. That’s what Randy Oliver said during the Four Pillars of Honey Bee Management, a conference that took place in October 2015 in Medina, Ohio
Randy Oliver is a Californian biologist who dedicated himself to beekeeping – running more than 1,000 hives together with his sons – as well as researching in order to provide information on the subject by relying on data rather than urban legends.
During his talk titled “Honey bee nutrition” he touched many fundamental aspects of bees’ life, and they are all related to pollen. Here are some of the things he said:
For humans, winter only means cold weather and short days. But for th bees, winter means they will not be able to collect pollen for a while. That’s why honeybees store honey as an energy resource they can later use during the winter.
What are honeycomb cells for? A number of cells contains a honey interface, where you can find either honey in open cells or nectar that hasn’t been turned into honey yet. The honey interface is located between an energy reserve - which is a group of sealed cells containing honey – and the brood. Between the honey interface and the brood there is a protein interface, where bees put pollen that will be consumed as quickly as possible – pollen is very nutritious and it can easily be infected by microbes and parasites. The sooner bees eat it, the fewer the chances these organisms got to it already.
Only nurse bees can digest pollen. Nurse bees are generally those bees that range from two to fifteen days from the day they got out of their capped cells. As they get older, bees’ digestive tract goes through some changes, so they lose the ability to digest pollen.
“Yes, my bees get to know me after a while” is a myth worth dispelling. In the summertime there is a complete turnover of the adult bees’ population every 42 days. So they do not have the time to get to know you. However, such a fast turnover will happen as long as the colony does not run out of pollen. Without the protein in the pollen, bees will not grow.
How much pollen does a colony need? During the summer, just keeping a colony healthy requires about 1-2 lbs of pollen every week, which equals to 100-200 g of protein per week, and even more than that for colony growth. During winter, the colony does not grow, so it will not need as much protein.
What happens if colonies run out of pollen? If there is a shortage of food – for example foraging activities stop due to bad weather – nurse bees will stop brood rearing. They will even eat the eggs laid by the queen, until pollen comes back in the hive. So the growing rate in the colony is not decided exclusively by the queen. Nurse bees have a say in the matter, and their decision is strictly linked to pollen.