One common reason for bees to remove larvae from the hive is the presence of the Varroa mite, a dangerous parasite that can threaten the entire colony. Bees can sense the presence of Varroa in pupating larvae and remove them as hygienic behavior to keep the mite population under control. Bees also remove dead or diseased larvae, such as those affected by chalk brood or foulbrood, to maintain a sanitary environment within the hive.
Why Would Bees Remove Larvae From a Hive?
Hygienic Behavior
One reason bees may remove larvae from the hive is to maintain cleanliness and prevent the spread of diseases or pests within the colony. Bees are known to keep a clean hive, and it’s common for them to eject dead bees and larvae. Those that look hard and chalky may be a sign of chalkbrood, which bees remove to prevent further spread.
Furthermore, observing bees removing larvae could be an indication of pest infestations, disease control, or removal of larvae that died due to extreme weather changes.
Cannibalism
Although less common, another way bees remove larvae from the hive is cannibalism. In some circumstances, when a colony is facing limited resources, such as food, bees may resort to cannibalizing their larvae to provide nutrition for the rest of the colony. In this case, there would be no evidence for the beekeeper to see because they will eat the larvae inside the hive.
Factors Contributing to Larvae Removal
Diseased or Infected Larvae
Honeybees developed hygienic behavior, which involves the removal of dead, diseased, or infected larvae from the hive. This behavior plays a crucial role in maintaining a healthy colony. When adult bees detect larvae that are infected or unhealthy, they uncap the cell and remove them from the hive to prevent the spread of infections and diseases in the colony.
Pests and Parasites
Larvae removal can also be attributed to pests and parasites, such as Varroa mites and wax moths. Varroa mites feed on the blood of developing bee larvae and can cause deformation and weakening of honeybees. Similarly, larvae of the greater wax moth can cause considerable damage to beeswax combs, which is why worker bees remove them from the hive.
Poor Nutrition
Larvae that do not receive adequate nutrition may be removed to preserve resources for healthier brood. Factors that affect nutrition include the availability of pollen and nectar, weather conditions, and the overall health of the colony. Ensuring that the bees have sufficient access to quality nutrition is crucial to promote the development of a strong and healthy brood.
Identifying the Cause in Your Hive
Examining the Brood Pattern
A healthy brood pattern appears compact and regular, with most cells filled with developing larvae. If you observe an irregular brood pattern or an unusually high number of empty cells, it may indicate a problem.
Looking for Signs of Disease or Infestation
Some common diseases and pests can cause bees to remove larvae from the hive. Specific issues to watch for include:
- Chalkbrood: A fungal brood disease caused by a spore-forming fungus that affects workers, drones, and queen larvae, making them susceptible to removal by bees (source).
- American and European foul brood: A bacterial brood disease that kills larvae causing abnormal brood patterns (source).
- Wax moth larvae: These pests can develop underneath the brood cappings, causing harm to larvae and filling the hive with destructive webbing, triggering the removal of larvae by bees (source).
- Varroa mites: Female mites enter the hive’s brood cells to reproduce, and their presence may lead to abnormal brood patterns and the removal of affected larvae (source).
Regularly inspecting your hive and looking for signs of disease or infestation can help you take appropriate action to address the cause of larvae removal.
Preventing and Managing Bee Larvae Removal
Maintaining Hive Health
Regularly inspect the hive and check for sufficient food supply, brood pattern, adequate ventilation, and overall bee population health. Beekeepers should also provide a clean water source and supplementary feeding if necessary. Adequate space within the hive helps prevent overcrowding, which can lead to stress and susceptibility to diseases and pests.
Beekeepers should follow recommended guidelines for treating diseases, using approved medications and techniques to minimize the risk of resistance development.
Controlling Pests and Parasites
Various pests and parasites, such as Varroa mites and small hive beetles, can lead to larvae removal. Adopt an integrated pest management approach and take proactive steps like using hygienic bees, mechanical trapping, and chemical treatments when necessary. When finding infested patties, remove and dispose of them immediately, wrapping them in several layers of plastic bags to prevent small hive beetles from escaping.
Conclusion
Bees removing larvae from the hive can be attributed to various factors such as pest infestations, disease control, or the removal of larvae that have died due to extreme weather changes. Beekeepers need to observe their bees’ behavior and understand the potential reasons contributing to the removal of larvae from the hive.
Bees may leave their hive due to several reasons, like uncomfortable living conditions, temperature extremes, poor ventilation, or lack of food and water. Beekeepers should be vigilant in maintaining the hive’s environment and keeping their bees healthy to minimize the likelihood of these issues arising.
