Video transcript: Virtual bees help to unravel complex causes of colony decline

You may wish to play the video in another window to watch it side by side with the transcript below. Alternatively, you can watch the video on our YouTube channel with captions.

March 2014

Dr Matthias Becher, University of Bath
BEEHAVE is a computer model that simulates a honey been colony on the basis of daily time steps . It shows the dynamics of the single honey bee colony and the foraging activities of the bees, so how much nectar and pollen they collect from the landscape, but it also includes the dynamics of varroa mites and it can address different conditions of weather and food availability in the landscape.

Video shows the BEEHAVE software in use.

So first you have to define the start conditions of the simulation. For example you would choose the default setting and then you can add the varroa mites and the beekeeper and press 'set up' and run the model.

The main window shows the colony dynamics each bar represents a cohort of bees. So for example you have the blue bars which represent eggs, yellow bars represent larvae and brown bars represent kept brood; the orange bars represents the in-hive workers, and foragers are shown as these little bees on top of the window moving to the right as they are getting older.

You can also see two flowers and green one and a red one and they represent the food patches. You can define the food provided at these patches in the green boxes on the right side for example you can define the quantity of nectar they provide on each day, the sugar concentration of the nectar, the pollen and the distance to the hive.

The sun and the cloud show the weather today and the two arrows indicate how pollen and honey stores have changed today.

So the whole video presents a single year. In the plot of the colony structure you can see that they start with about 10,000 bees then it goes down in the late winter, early spring, then the colony size increases for each of its maximum in summer and then declines again during autumn and winter.

You can also see the number of varroa mites in the mite plot. The varroa mites are parasites that transmit viruses that can affect the bee health which means that bees have a reduced life span and an increased mortality, and you can see that the number of mites is dramatically increasing but then when the bee keepers start to treat against the mites you see that they are declining and almost all mites have gone at the end of the treatment.

You can also see the plot with the stores in the hive, for example the honey stores and the pollen stores; we can also stimulate how forage availability in the landscape interacts with the presence of the varroa mites, and we see that at least to some degree improved forage availability in the landscape can mitigate the impact of varroa mites.

Vidoe shows beehives out in the field.

The advantage of a model is that we can create new hypotheses to test what we can do in the field studies, models are cheap to produce and quick to run. The BEEHAVE model can be used by scientists and researchers but it can also be used by anyone interested in honeybees and especially beekeepers.

Honeybees play an important role not only because they produce honey but mainly because they are important pollinators.

So we will keep on working with the BEEHAVE model and address all sorts of questions. For example how the landscape and the food availability in the landscape will effect colony dynamics, and also how pesticides might affect the colony dynamics.



  • Images: Dr Petere Kennedy, University of Exeter, and Rotham sted Research
  • Music: 'Mr Cacophony Fillemed in Reverse' from cinephonix.com