Why Did My Bees Die? 9 Common Mistakes

You did everything right. You watched the videos. You read the books. And now your hive is dead, and you're standing in your backyard trying to figure out what went wrong.

First: you're not alone. The annual colony loss rate exceeds 55%. Even experienced beekeepers lose hives. Some losses are unavoidable—a poorly mated queen, a pesticide kill, a freak cold snap. But many losses are preventable.

Here are the 9 most common mistakes that kill colonies, ranked roughly by how often they're the culprit.

1. Not Treating for Varroa Mites

This is #1 for a reason. It kills more colonies than everything else combined.

Varroa destructor mites are parasites that feed on bees' fat bodies and transmit deadly viruses—Deformed Wing Virus, Acute Bee Paralysis Virus, and others. Every colony has them. Untreated, mites will kill your colony within 1–2 years, usually during winter.

The trap: Mite damage is invisible until it's too late. A colony can look healthy all summer while mite populations grow exponentially. By the time you see bees with crumpled wings or a rapidly shrinking population, the damage is done.

The fix: Monitor mite levels monthly with alcohol washes. Treat when levels exceed 3%. Treat in late summer/early fall regardless—this protects the winter bees that need to survive until spring.

Signs your colony died from mites: Dead bees with deformed wings, spotty brood pattern before collapse, rapid population decline in fall, very few bees left in the hive despite remaining honey stores.

2. Starvation

New beekeepers often don't realize how much food bees need—or how fast they can run out.

A new package or nuc arrives with nothing. They need to draw wax (8 lbs of honey to make 1 lb of wax), raise brood, and stockpile for winter. An established colony needs 60–90 pounds of honey to survive winter, depending on your climate.

Starvation happens when beekeepers stop feeding too soon, take too much honey, or underestimate winter needs. It also happens in late winter/early spring, when stores run out just before the first nectar flow.

The fix: Feed new colonies aggressively until they stop taking syrup. Don't harvest honey from first-year hives. "Heft" your hives in winter—lift the back to feel the weight. Light = emergency feeding needed.

Signs your colony died from starvation: Dead bees headfirst in cells (they climbed in looking for food), empty frames, bees clustered on empty comb, often a small cluster frozen in place.

3. Queen Failure

The queen is the colony's reproductive future. When she fails—dies, becomes a drone layer, or simply stops laying well—the colony spirals downward.

Queen problems can be subtle. A failing queen may still be present but laying poorly (spotty brood, excessive drones). By the time you notice population decline, the colony may be past saving.

The fix: Learn to assess brood patterns. Good: solid, compact, mostly worker brood. Bad: scattered, lots of gaps, excessive drone cells. If your queen is failing, requeen immediately—don't wait for the colony to solve it themselves.

Signs your colony died from queen failure: Dwindling population over time, lots of drone brood in worker cells, multiple queen cells (supersedure attempts), laying workers (multiple eggs per cell) if they went queenless.

4. Going into Winter Weak

A strong colony can survive winter. A weak one can't. "Weak" means too few bees to maintain cluster temperature, or a colony still recovering from summer problems.

Common reasons colonies are weak going into fall: they swarmed (lost half their population), they had mite damage all summer, they had queen issues, or the beekeeper neglected them during summer dearth.

The fix: Assess colony strength in September. If a colony is too weak to survive winter (small cluster, few bees covering frames), consider combining it with a stronger hive. One strong hive beats two weak ones.

5. Moisture (Not Cold) in Winter

Here's a surprise: bees don't die from cold. They die from moisture.

The winter cluster generates heat and moisture. In a well-ventilated hive, moisture escapes. In a poorly ventilated hive, moisture condenses on the cold inner cover and drips back onto the cluster—wetting the bees, who then chill and die.

The fix: Ensure upper ventilation. Use a notched inner cover, drill a small hole in the upper box, or add a moisture board/quilt box. Don't seal the hive "to keep them warm"—they need airflow.

Signs your colony died from moisture: Dead bees are wet or moldy, mold on frames, condensation inside the cover, sometimes the entire cluster died in place suddenly.

6. Swarming and Not Recovering

Swarming is natural—it's how colonies reproduce. But a colony that swarms loses half its population and its laying queen. If this happens mid-season and you don't manage it, the colony may not recover before winter.

The new queen needs to emerge, mate, and start laying—a 2–4 week gap with no new brood. The reduced population may not build back up in time.

The fix: Learn swarm prevention: give adequate space, practice "checkerboarding" or reversing brood boxes, and don't let the brood nest get congested. If they do swarm, make sure the new queen successfully mates and starts laying.

7. Pesticide Exposure

Bees forage up to 3 miles from home. If a neighbor sprays pesticides on blooming plants, your bees can bring poison back to the hive.

Neonicotinoids are particularly insidious—they're systemic (in the plant's nectar and pollen) and can accumulate over time, weakening the colony without an obvious "kill event."

The fix: Talk to neighbors about not spraying during bloom. Register your hives with programs like "FieldWatch" or "BeeWhere" that alert pesticide applicators to your presence. Provide diverse forage so bees aren't dependent on one source.

Signs of pesticide kill: Sudden pile of dead bees at the hive entrance, bees crawling/trembling/dying, tongue-out dead bees, rapid population collapse over days.

8. Disease (American Foulbrood)

American Foulbrood (AFB) is a bacterial disease that kills larvae. It's rare compared to mites, but when it hits, it's devastating—and legally reportable in most states.

AFB spores are nearly indestructible. They persist in equipment for decades. If your hive has AFB, the standard protocol is burning the hive, frames, and all equipment. There's no treatment that eliminates the spores.

The fix: Learn to recognize AFB: sunken, perforated cappings; brown, gooey larvae that "rope" when you stick a toothpick in them; foul smell. If you suspect AFB, contact your state apiarist immediately.

Prevention: Don't buy used equipment from unknown sources. Don't feed bees honey from unknown sources (it can contain spores). Get your hives inspected regularly.

9. "Leave Them Alone" Philosophy

Some new beekeepers romanticize hands-off beekeeping. "Let nature take its course." "Bees survived for millions of years without us."

The problem: managed bees in the modern era face challenges wild bees didn't. Varroa mites arrived in the US in 1987. Habitat loss has reduced forage diversity. Pesticide pressure has increased. Feral colonies crash and are constantly replenished by swarms from managed hives.

Bees are livestock, not wildlife. They need active management to survive in the modern environment.

The fix: Accept that managing bees means intervening. Monitor mite levels and treat when necessary. Feed when they're hungry. Requeen when the queen is failing. Inspect regularly to catch problems early.

"Treatment-free" beekeeping can work—but it requires rigorous breeding, intensive management, high loss tolerance, and years of experience. It's not appropriate for beginners.

How to Do a "Hive Autopsy"

When a colony dies, don't just shrug and start over. Figure out why. Here's how:

1. Check for food: Are the frames full of honey, or empty? Empty = starvation. Full = something else killed them.
2. Look at dead bees: Bees headfirst in cells = starvation. Wet/moldy = moisture. Deformed wings = mites. Tongues out = possibly pesticides.
3. Check the brood pattern: Spotty brood before death = queen problems or mite damage. Sunken cappings with holes = possibly AFB (get it tested).
4. Estimate cluster size: Tiny cluster = they went into winter too weak. Normal cluster = something killed them quickly (moisture, disease).
5. Look for the queen: Can you find her body? Was she marked? Sometimes you'll find a dead queen, which helps narrow down the timeline.

If you can't figure it out, ask for help. Post photos in your local bee club's Facebook group. Bring samples to a club meeting. Your state apiarist may offer free consultations.

The Most Important Lesson

Losing a colony hurts. It's okay to feel frustrated, sad, or guilty. But don't let it stop you.

Most successful beekeepers lost their first colony. The difference between someone who becomes a good beekeeper and someone who quits is what happens after the loss. Figure out what went wrong. Learn from it. Try again.

Your second colony will benefit from everything you learned from your first. That's not a consolation prize—that's how this works.