When is Dearth?
Dearth is a difficult time for all bee colonies, and it occurs when there is a shortage of nectar-producing flowers in a colony’s foraging region. Flowers that normally produce nectar may not during times of stress, such as a drought. Dearth can be disastrous to colonies because a whole population can starve to death if a beekeeper does not prepare correctly.
Signs of a Nectar Dearth
When dearth starts, colony behavior will change in a couple ways. First of all, bees are louder, and they become agitated. To cool off they move around the outside of the hive, which is known as “bearding”, but it can look like the start of a swarm. Secondly, bees double-check flowers, which is not something they normally do. Beekeepers also notice that bees become more curious and check out new smells or go to odd places like near vehicles or recycling bins. Lastly, bees appear more aggressive during dearth. They may seem more defensive of their hive, which is normal especially because robbing is common during dearth. Robbing is when bees go to hives that are not their own and steal nectar, which is one of the worst side-effects of dearth since many bees usually end up dead.
When does it happen?
What exactly “dearth” means and when it happens depends on where someone lives. Generally, nectar dearth is most common in summer and winter, but it can happen anytime during the growing season that there are changes in the environment, such as a drought or a significant change in temperature.
Summer dearth tends to be the most devastating because most bees and beekeepers are not prepared for it as they are for the winter dearth. There is a point during the summer, which is different for every area, when temperatures rise and the flow of nectar decelerates. It also occurs during the transition between seasons which is when old plants die and new plants grow.
- Starts last week of July/ first week of August- Florida (Lady Lake)
- Mid-June to October- Florida (Jacksonville)
- Starts second/third week of July- Washington (Seattle)
- Starts mid-June- California (Sacramento)
- End bloom of Indian Blanket and Horsemint- Texas (Austin)
- End bloom of Thistle and Horsemint- Texas (Greenville)
- July to August- Ohio (Belpre)
- Starts late June- Georgia (Athens)
There is not much information on the exact time dearth starts in each region, because it varies and depends on the climate and weather patterns. For a general idea, this bee foraging map can be used to see the end bloom month for significant nectar sources for each region, which would probably mark the start of dearth for each region respectively. In addition, this drought monitor is a good resource to use when preparing for death. During the summer dearth tends to start when plants bloom and die off, grass turns brown, and when vegetable plants stop producing new flowers. July and August are the most prominent months of dearth in the United States. Winter dearth is usually less devastating because bees have their stores of honey to rely on.
What can a beekeeper do to help their bees during dearth?
There is not much that a beekeeper can do to prevent dearth, but there are some things they can do to prepare for it. Beekeepers can reduce the entrance to a hive to make it easier for bees to defend their hive from robbers. Robbing screens are also an effective way to minimize robbing. Beekeepers can also choose to provide food for their bees such as pollen patties or a sugar syrup mixture. It is also important for beekeepers to know what plants produce nectar in their local areas, especially the late-blooming ones, so they can choose to plant them for their bees to access during dearth.