Why is My Beehive Empty?
Beekeepers expect to find their hives bustling with thousands of bees. Opening up a beehive box only to find it empty can be alarming and disappointing. However, empty hives are not always a total loss. There are several reasons a hive may be vacant and action steps a beekeeper can take. Here is an overview of common causes and solutions for suddenly finding empty frames and no bees in a once flourishing colony.
Swarming Bees
A prime reason for finding empty hives is a natural process called swarming. Swarming occurs when a hive reproduces by splitting off a secondary colony. As the bee population grows in spring and summer, crowding pressures the queen bee and about half the workers to leave the hive to find a new home. Scouting bees will choose a nearby site like a tree branch to cluster around the queen and start a breakaway colony. This dramatic mass exit of thousands of bees can leave the original hive nearly empty. It takes time for the remaining bees to regrow the population. Spotting groups of bees clustered outside or in unusual locations indicates a swarm has occurred. The parent colony is not dead but just decreased while establishing a new one elsewhere.
Absconded Bees
Rather than swarming to reproduce, sometimes an entire colony will abscond and abandon the hive for other reasons. Unlike gradual swarming, absconding is a sudden, permanent relocation of all bees from the colony. Triggers for absconding include pests, diseases, insufficient food sources, and other uninhabitable conditions. If bees unexpectedly abscond, the beekeeper will find no trace of the queen or workers remaining in the hive. Absconding bees rarely return, leaving empty frames behind. The cause is likely an environment the colony found intolerable. However, other nearby hives may be unaffected.
Dead or Dwindling Bees
While a total disappearance of bees usually indicates swarming or absconding, opening a hive to find only a small handful of bees moving sluggishly about the frames often means the colony has collapsed or declined. Population drop can result from stressors like mites, diseases, cold temperatures, or a failing queen. Bees may lay dead at the bottom of otherwise vacant hives. Look for eggs and larvae to determine if a struggling queen is still present but unable to sustain the colony alone. Dwindling bees are a dire sign the hive is deteriorating or has perished already.
Robbed Honey Stores
Another possibility for empty frames is robbed honey stores. Weaker hives low on honey or left inadvertently unsealed risk being invaded and picked clean by robber bees from other colonies. Intruding bees will steal every last drop of honey, pollen, and propolis once inside, stripping the comb down to bare wax. Robbing may continue over weeks until the target hive is entirely emptied. The ruthless robbers do not kill off bees but simply ransack their kitchen, leaving nothing behind. No other symptoms initially appear except the missing honey previously stored.
Pest Damage or Theft
Ruined combs or toppled hives provide clues that destructive bears, raccoons, rats, or skunks may have raided the colony and chased away or killed the bees. These bold pests go after honey and typically damage equipment in the process. Carefully assess for chewed boxes, scratched frames, feces, or tracks around the apiary. Stinging insects like hornets may also usurp a weakened hive and kill off its inhabitants. Equipment theft can be another cause for mysteriously absent bees, though leave-behinds like fresh pallet markings often provide clues to follow up on.
Apiary Mistakes
Beekeeper errors can unintentionally lead to empty hives. Harvesting too much honey without leaving adequate winter food stores causes starvation. Failing to replace the queen leads to a dying colony. Exposure to agricultural sprays poisons bees away from the nest. Moving or jarring hives when the bees are not safely inside leads to mass casualties. Knocking frames out of place during inspections can disrupt brood rearing. Any serious or chronic mismanagement gives bees reasons to flee and abandon hives. An experienced mentor can identify potential oversight issues.
Queen Events
Problems with the queen herself are a common cause of vanishing bees. If the queen dies from injury, disease, or old age, workers sense it immediately. Bees may hastily flee the hive when they find themselves suddenly queenless. Virgin replacement queens sometimes go on mating flights but fail to return. Swarming bees may also accidentally leave without the new queen, dooming the remaining colony. In a queen crisis, worker bees have limited survival time until the population dwindles away. Regular requeening helps prevent collapse from queen loss.
Taking Action for Empty Hives
When faced with inexplicably vacant hives, beekeepers can investigate and remedy the issue:
- Assess calmly: Note indicators like queen cells, signs of disease, or damage. Consider colony temperament and any disruptions.
- Move hives immediately: Bring empty but intact hives into storage or merge with robust colonies to protect equipment.
- Search apiary carefully: Look on the ground and in surrounding areas for dead bee buildup, discarded wax, or live swarms.
- Set bait hives: Lure swarmed bees into awaiting empty boxes strategically placed with lemongrass oil.
- Join nearby nucs: Add frames of eggs and brood from other hives into the vacant equipment so bees can regroup.
- Requeen: Order replacement queens for hives repeatedly abandoned or headed by failing queens.
- Address pest issues: Guard from predators and use integrated pest management against hive beetles, moths, mites, etc.
- Ensure adequate food: Supplement light reserves with sugar water, honey slurry, or new pollen sources.
- Eliminate apiary hazards: Remove any repellents or toxins around the hives.
- Improve ventilation: Absconding bees often dislike excessive heat, humidity, or congestion.
- Split robust hives: Use frames of eggs from your strongest hives to repopulate emptied equipment.
With detective work and prompt action, many empty hives can recover resilience against future vacancies.
Preventing Empty Hives
Beekeepers can take proactive steps to reduce chances of opening up to missing bees and vacant equipment:
- Select docile stock: Less aggressive bees with strong swarming instincts are less likely to abscond.
- Ensure adequate space: Add boxes early in the season and as populations expand. Prevent overcrowding.
- Keep entrances clear: Do not let weeds or debris block bees from easily coming and going.
- Limit disruptive inspections: Check hives gently and only as needed to reduce stress.
- Control parasites: Use screens, traps, and non-toxic controls to keep pests away.
- Maintain optimal habitat: Site hives with adequate food, water, shade, ventilation, etc.
- Exclude robbers: Close off hives when handling any except the strongest colonies.
- Keep records: Note dates and observations for each colony to inform health evaluations.
- Check food reserves: Ensure adequate honey for the full dormant season, supplementing if needed.
- Requeen annually: Young, productive queens prevent collapse and inspire colony loyalty.
With attentive care and quick problem-solving, beekeepers can enjoy consistently active hives and satisfying honey harvests. An empty hive can be discouraging but also presents an opportunity to correct issues and start fresh. With nature’s resilience and the beekeeper’s aid, most vacant hives soon hum with life again.