Understanding and Managing Dearth: A Guide to this Critical Time for Honey Bees

For honey bees, one of the most challenging periods they face is called a "dearth" – a time when nectar and pollen sources become scarce or unavailable. Understanding what dearth means, how to recognize it, and how to help your colonies through these difficult periods is crucial for successful beekeeping.

What is Dearth?

Dearth, in beekeeping terms, refers to a period when there is a significant shortage of nectar-producing flowers in the environment. During these times, foraging bees struggle to find adequate food sources to sustain their colony. This natural phenomenon can occur for various reasons and at different times throughout the beekeeping season.

Dearth periods are a natural part of the ecosystem's rhythm. They occur because flowering plants don't bloom continuously throughout the year. Instead, most plants have specific blooming periods, and there are inevitable gaps between major nectar flows. Weather patterns, seasonal changes, and human activities can all contribute to these challenging periods for bee colonies.

Types and Timing of Dearth

There are generally three types of dearth periods that beekeepers encounter:

Summer Dearth is perhaps the most common and challenging for both bees and beekeepers. This typically occurs during the hottest months of summer, usually July through September in most temperate regions. During this period, spring flowers have finished blooming, and fall flowers haven't yet begun. The intense heat and lack of rain can cause existing flowers to stop producing nectar or produce it in much smaller quantities.

Winter Dearth is the most predictable type, occurring when most plants are dormant due to cold temperatures. In regions with harsh winters, this can last several months, from late fall through early spring. However, in milder climates, winter dearth might be shorter and less severe, with some plants continuing to provide occasional nectar sources.

Drought-Induced Dearth can happen at any time during the growing season when lack of rainfall causes plants to conserve water by reducing or stopping nectar production. Even if flowers are present, they may not be producing the nectar that bees need. This type of dearth can be particularly challenging because it's unpredictable and can coincide with times when beekeepers expect abundant nectar flows.

The timing and severity of dearth periods vary significantly depending on your geographic location, local climate patterns, and the types of plants in your area. This is why it's crucial to learn about your local beekeeping conditions and connect with experienced local beekeepers who understand regional patterns.

Recognizing the Signs of Dearth

Learning to identify when your colonies are experiencing dearth is a critical skill that develops with experience. The signs can be subtle at first but become more pronounced as the shortage continues.

Behavioral Changes are often the first indicators. During abundant nectar flows, you'll notice heavy traffic of forager bees coming and going from the hive, many returning with visible pollen loads on their legs. During dearth, this activity decreases dramatically. Foraging flights become longer as bees search farther for food sources, and fewer bees return with pollen loads.

Increased Defensiveness is another common sign. When food is scarce, bees become more protective of their stored resources. You may notice that your normally docile colonies become more aggressive during inspections. They may be quicker to sting and more likely to follow you away from the hive. This heightened defensiveness is their natural response to protecting what little food they have.

Robbing Behavior often accompanies dearth periods. Stronger colonies may attempt to steal honey from weaker ones, leading to fighting at hive entrances. You might observe bees trying to sting each other, a louder more agitated buzzing sound at the entrance, bees trying to get into the hive in areas other than the main entrance, dead bees on the ground by hte main entrance and a lot of bees coming into or going out of the hive quickly (as if they're trying to leave before being spotted by a guard).

Inside the hive you'll notice that bees are not drawing out new wax comb. and the queen may reduce her egg-laying rate or stop entirely, as the colony conserves resources. You might also observe that there is less honey in the hive and no drone brood or adult drones present.

Weight Changes in your hives can be one of the most reliable indicators. Many experienced beekeepers regularly lift their hives from the back to gauge weight. During dearth, you'll notice hives becoming noticeably lighter as bees consume their honey stores without adding new resources. Hive scales are another way you can monitor your hive's weight throughout the season.

How to Help Your Colonies During Dearth

Water sources become critically important during dearth, especially in hot weather. Ensure your bees have access to clean, reliable water sources. Bees need water for diluting honey, cooling the hive, and various metabolic processes. A shallow water source with landing areas (like stones or wood pieces) works well. Bowls, bird baths, trays and pans left outside and refilled with water daily can all be used as a water source for your bees. My bees love landing on the pieces of moss I laid in a old plastic sled.

Reducing hive inspections during severe dearth helps minimize stress on the colony. Each inspection requires bees to use energy to re-establish the hive's organization and temperature control. Limit inspections to essential activities only, and work quickly and efficiently when you must open the hive. Inspections also encourage robbing as bees in the area can smell the hive more so when it is open and frames are outside.

Consolidating boxes by removing frames whose cells have no brood on them and few bees will make it easier for the bees in the hive to defend the smaller space. See the video at the top of the article for signs a hive should be consolidated. In extreme cases where a hive is just a few frames of brood, you may want to combine them with another hive.

Feeding is the most obvious way to help colonies that are low in food supplies but one I use as a last resort.  Sugar syrup can substitute for nectar, providing the carbohydrates bees need for energy. For emergency feeding during active dearth, use a 1:1 ratio of sugar to water (by weight), which closely mimics natural nectar concentration. Feed in small quantities regularly rather than providing large amounts infrequently, as this more closely resembles natural foraging patterns. I prefer to put syrup in glass jars with a lid that has a few holes poked into the top. This cuts back on the amount of robbing that can happen when feeding your bees. Only feed syrup if the population is low, the queen has stopped laying or slowed down considerably or the hive does not have enough food stored up to get them through winter. 

What NOT to Do During Dearth

Well-intentioned actions can sometimes harm colonies more than help them. Understanding what to avoid during dearth is equally important as knowing how to help.

Avoid over-feeding your colonies. While it may seem logical to provide abundant food during scarcity, too much feeding can cause problems. Excess sugar syrup can ferment, potentially poisoning bees. It can also stimulate the queen to resume heavy egg-laying when the colony isn't prepared to support increased brood production.

Don't leave honey, pollen, propolis, beeswax, honeycomb or used beekeeping equipment outside the hives. This will encourage robbing during a time of dearth.

Avoid adding supers during dearth unless you're feeding heavily. Empty supers give bees more space to defend and maintain, which uses energy the colony needs to conserve. It's better to keep the colony's space appropriate to their population and resources.

Resist the urge to frequently check on struggling colonies. While your concern is understandable, constant inspections stress bees and disrupt their conservation efforts. Trust your initial assessment and give colonies time to work through the challenges.

Prevention and Preparation Strategies

The best approach to managing dearth is preparation and prevention. Understanding your local environment and planning ahead can significantly reduce the impact of these challenging periods on your colonies.

Learn your local patterns by connecting with experienced local beekeepers, joining regional beekeeping associations, and keeping detailed records of your observations. Track when dearth periods typically occur in your area, how long they last, and which colonies handle them best.

Plant bee-friendly flowers that bloom during typical dearth periods. Late-season flowers like asters, goldenrod, and sunflowers can provide crucial late-summer and fall nectar sources. Even small plantings can make a difference for nearby colonies.

Maintain strong colonies heading into known dearth periods. Strong colonies with adequate population and good honey stores are much more likely to survive food shortages. This means ensuring proper nutrition, disease management, and population levels during abundant times.

Keep detailed records of your colonies' performance during different conditions. Note which colonies struggle during dearth and which thrive. This information helps you make better breeding and management decisions over time.

Conclusion

Dearth is a natural challenge that all beekeepers must understand and manage. While these periods can be stressful for both bees and beekeepers, they're part of the natural cycle that has shaped honey bee behavior for millions of years. Your role as a beekeeper is to recognize when intervention is needed and provide appropriate support while avoiding actions that might inadvertently harm your colonies.

Remember that every region and every season presents unique challenges. What works in one location may not be appropriate in another, and what's necessary in a severe dearth year may be excessive in a mild one. Develop your skills through careful observation, detailed record-keeping, and connection with other local beekeepers.

With experience, you'll learn to read the signs early, prepare your colonies appropriately, and provide the right level of support when needed. This knowledge will help ensure your colonies not only survive dearth periods but emerge strong and ready to take advantage of the next nectar flow. The key is finding the balance between helpful intervention and allowing your bees to do what they've evolved to do naturally – survive and thrive through the cycles of abundance and scarcity that define their world.