Honeybee Cleansing Flights

Cleansing Flights – What Are They? 

Many might not be aware that honeybees exhibit a form of “house-training,” making concerted efforts to avoid defecating inside or on the immediate exterior of their hive. During warmer months like spring and summer, weather permitting, they frequently embark on journeys solely to eliminate waste, well away from the entrance of their hive. These excursions are termed “cleansing flights” for their waste elimination purpose and “clearing flights” when the mission involves removing debris or deceased bees.

Worker bees undertake these flights either solo or in groups, venturing a short distance from the hive to expel waste or dispose of collected debris before returning. This practice is crucial for maintaining hive cleanliness and hygiene, ensuring a salubrious environment for the colony’s sustenance.

If bees begin defecating within the hive or on its landing board, it prompts a need for observation and questioning to ascertain if such unusual behavior hints at underlying health concerns.

Dysentery in honeybees results from waste accumulation to a point where a bee must relieve herself, regardless of location.

When to Raise the Alarm

In colder climates, particularly throughout winter, bees may remain confined within their hive for prolonged periods, conserving warmth. This confinement prevents them from performing cleansing flights. Similarly, extended spells of adverse weather, like heavy rain or air pollution from wildfires, may restrict these essential flights.

On warmer days, surpassing 40 degrees Fahrenheit, bees seize the opportunity for cleansing flights. Observing the hive’s exterior and landing board for yellow stains can provide insights:

– Stains on the ground or in front of the hives are normal.

– Staining on the landing board or just in front of the hive is acceptable if it follows prolonged inclement weather.

– Internal hive stains, visible upon thorough inspection, require a deeper inquiry into potential health issues within the colony.

Signs of Dysentery Inside the Hive

Recognizing dysentery signs inside the hive, such as yellow, brown to black staining on frames or sidewalls, could indicate issues, including the possibility of Nosema, a challenging disease. Although internal staining doesn’t always point to Nosema, it warrants consideration of testing for this or other conditions. 

Nosema: A Closer Look

Not all signs of dysentery necessarily mean Nosema is present, but they could indicate a potential infection. If Nosema is suspected, it’s advisable to collect samples of bees from the hive for testing and confirmation. Learn more about Nosema testing here

Typically associated with overwintering challenges, dysentery, and consequently Nosema, can occur any time of the year. Monitoring your hive for digestive irregularities is crucial for timely intervention and treatment if necessary.

Reflective Questions for Beekeepers

Observing dysentery symptoms within a hive prompts critical reflection on various factors, from nutrition and environmental stressors to fungal and viral infections and other parasites. Questions regarding bee feeding practices, changes in moisture levels within the hive, and the presence of high level of Nosema spores can guide beekeepers in pinpointing the cause of dysentery symptoms and formulating a response.

Ask yourself these questions to help determine why your bees are experiencing dysentery symptoms and what you may need to do to help:

•     How did I feed my bees?  – Sometimes feeding sugar syrup too early in the season, especially during extended periods of rain or cold can cause dysentery in honeybees.

•     Did you feed any patties (winter/pollen)? – Both winter and pollen patties contain some protein which can increase fecal production.

•     How long were my bees trapped inside? – Was there a long time that they were stuck inside the hive (i.e. during the cold winter months where many days were below 40 degrees F, or long periods of rain)?

•     How much moisture was inside the hive? Was there a sudden increase in humidity? – Excessive humidity and moisture within a beehive can increase a honeybee’s total body weight fecal accumulation. This means that they are holding in more feces and moisture than they can physically hold and may not make it outside to defecate.

•     Were they only fed dark honey? (like buckwheat, for instance, or any feed high in ash content). Some bees are unable to stomach darker honey well and it could cause increased staining or dark feces.

•     Did you re-use any honey/pollen/equipment that was stained from fecal matter in the past? – They may contain Nosema spores. If staining occurs on any equipment, even if it’s old, the spores could remain active and cause dysentery symptoms in other colonies.


Noticing deviations from normal bee behavior (like defecating inside the hive) warrants a thoughtful assessment of potential causes. While not always a sign of severe issues, recognizing potential problems early can significantly contribute to your bees’ health and vitality.

Vigilant observation, both outside and inside the hive as conditions allow, coupled with prompt action to address any symptoms, underscores responsible beekeeping practices. Testing and treating issues like Nosema promptly can profoundly impact your colony’s well-being.

Learn More

Read more about the threat of Nosema and other threats to bees in our Overview of the Main Threats to Bees lesson. A great reference on many issues that affect honeybees, including Nosema, can be found in “A Field Guide to Bee Maladies“, available through the PerfectBee Store here

Colony members (learn more about Colony Membership here) can check out the lesson on Nosema and Chalkbrood to learn even more.