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Population Dynamics of Honey Bee Colonies

Seasonal changes in honey bee numbers and stages of bee developement along with seasonal changes in the comb requirements of such colonies.

The months of the year are laid out like a clock face with January situated at one O'Clock. The centre represents the origin and the coloured segments represent quantities. Each Pixel from the origin represents 200 bees. The red area represents worker bee numbers and the brown area represents the difference between the swarming and non swarming situation. The diagram represents a situation without the presence of varroa. The data at right is an averaging of the seasons 1984 to 1992 on the Leicestershire/Warwickshire border at Ashby-De-La-Zouch. The numbers are estimated, but they are reasonably consistant.

The months of the year are laid out like a clock face with January situated at one O'Clock. The centre represents the origin and the coloured segments represent quantities. Each Pixel from the origin represents 200 bees.

The red area represents worker bee numbers and the brown area represents the difference between the swarming and non swarming situation.

The diagram represents a situation without the presence of varroa.

The data at right is an averaging of the seasons 1984 to 1992 on the Leicestershire/Warwickshire border at Ashby-De-La-Zouch. The numbers are estimated, but they are reasonably consistant.

Annual cycle of honey bee numbers in normal graphic form

The graph shown above came from Dick Sleath, I am not sure whether the data was from his bees or some other source (he died some years ago and the original was among his lecturing notes), but if the data was from his bees the geographic location would not have been more than a few miles fron the site that my data came from. The number of foragers available for nectar and pollen gathering affect both the future brood numbers and the honey gathering ability. I do not have data that gives forager numbers for a swarmed colony, but it would reach it's peak about a month earlier and the numbers would be reduced. The numbers would not be as depleted as you may think from the numbers lost to the swarm as many young bees would turn to foraging earlier to balance thing up a bit. If I find suitable data I will add it here for completeness sake.

The graph shown above came from Dick Sleath, I am not sure whether the data was from his bees or some other source (he died some years ago and the original was among his lecturing notes), but if the data was from his bees the geographic location would not have been more than a few miles fron the site that my data came from.

The number of foragers available for nectar and pollen gathering affect both the future brood numbers and the honey gathering ability. I do not have data that gives forager numbers for a swarmed colony, but it would reach it's peak about a month earlier and the numbers would be reduced. The numbers would not be as depleted as you may think from the numbers lost to the swarm as many young bees would turn to foraging earlier to balance thing up a bit.

If I find suitable data I will add it here for completeness sake.

The three diagrams below are (left) the number of eggs laid (centre) the number of open brood and (right) the number of cells containing sealed brood. For consistacy with other pages the cells are counted as "open brood" after 3 days from being laid. The scale here is 10 cells per pixel.

Sealed brood/open brood ratio

Following on from the two sets of data above centre and above right, they can be combined to produce the chart at right... We can see how the ratio of sealed brood to open brood changes as the poulation rises and then falls again after the summer. It is imoportant that beekeepers get a good grasp of this ratio and it's changes in the area that they live in, as much information about seasonal development can be interpreted or implied from this ratio and much swarming can be avoided, simply by being able to provide enough room early enough.

Annual cycle of drone availability within the environment Annual cycle of drone numbers in a colony The two diagrams depict drone numbers, in the left one the numbers are of drones in a given colony. The drone availability diagram at right, shows relative values rather than actual numbers, because some hives retain drones throughout the winter, as oposed to the left hand diagram which indicates almost zero drones from October to almost the end of April.

It should be noted that availability does not indicate ability to mate or fertility.

The representation is 20 drones per pixel.

Seasonal pressure on the size of cell constructed This data has taken much time to gather and digest, the thinking behind it is a little obscure. There are some people that are convinced that this is a significant reason why cell sizes have increased in managed brood nests, but much more data is needed to be certain of the effect and it's possible causes. My interpretation of this behaviour stems from data collected by Dennis Murrell, there are links to Dennis' work in the referances near the bottom of the nest integrity page.

Basically The inner of the five circles represents the "natural avarage" cellsize for a given strain of bee (whatever that may be in numerical terms).

The red line represents a colony that will not swarm in a particular season or the parent colony of a swarmed stock and the blue line represents the swarm component of a colony that has swarmed.

The gaps between the circles represents about 0.1 mm per ring.

Dave Cushman.

Page created summer 2001

Page updated 30/11/2022

Written... Summer 2001, Revised... 22 August 2001, Upgraded... 05 September 2006,