The small hive beetle (SHB) is an invasive beehive pest that can destroy entire honey bee colonies. Originally from Africa’s sub-Sahara, they found their way to Florida in the 1990s and have aggressively established a foothold in more than 30 states.
Small hive beetles multiply rapidly, and an infestation is a cause for concern with beekeepers. As with any threat, quick identification of the problem will reduce the damage. This guide looks at the symptoms of small hive beetle and how to properly inspect the hive so that they don’t go unnoticed.
What are the symptoms of small hive beetle?
To identify SHB, beekeepers should look for signs like an unpleasant smell and visual evidence of beetles or larvae. Other common symptoms include clumps of eggs in hidden areas, slimy comb, discolored honey, and honey trails. Heavily infested hives are easy to recognize but diagnosing the issue in the early stages is a lot more challenging.
1. Unpleasant smell
Hives with an infestation of SHB often give off a pungent fragrance of rotting oranges. Beekeepers often notice the stench before removing the lid.
Foul aromas are the result of frothing, fermented honey. Beekeepers with poor smell will notice the affected honey dripping from cells.
2. Beetles in the hive
The best way to work out if a hive has SHB is to identify them physically. Look for tiny blackish-brown beetles scuttling across the comb or trying to hide in small crevices.
Adult beetles are often difficult to observe. We recommend following our advice further down the page on inspecting a hive for SHB.
3. Beetle larvae
During inspections, look to see if larvae are burrowing through the brood or eating food stores. While adult beetles are quick to hide, larvae don’t have the same speed. They may be grouped in clumps in the corner of frames or a comb cell.
Even if they are no longer there, the damage they caused signals their presence. Look for damaged or destroyed comb and cappings.
Tip: Learn the SHB development stages to understand their lifecycle and how better to combat them.
4. Clumps of eggs
Suspicious clumps of eggs are a giveaway sign that small hive beetles have settled in. They look like small rice grains found in hive cracks and recesses.
5. Slimy comb
Contaminated honeycomb will have a slimy appearance due to the presence of yeast (K. ohmeri). Once the comb has reached this stage, it will often have an accompanying odor which we mentioned above.
6. Discolored honey
Honey, darker than usual, is a strong signal that SHB has taken over the hive. The discoloration results from larvae defecating in honey.
7. Honey trails
As beetle larvae develop, they crawl from super boxes towards the soil to pupate. During this migration, honey gets trailed across the hive, leaving telltale hints for beekeepers.
Hint: Beekeepers can reduce the chance of their hives getting infested by pests. Check out our guide on how to prevent small hive beetle. If it’s too late, you may want to read up on small hive beetle treatment methods.
How to inspect hives for small hive beetle
The detection of SHB can be complicated if their numbers are low. They typically scatter towards dark, hidden areas once the hive gets opened. A favorite hiding spot is the rear side of the hive’s bottom board, so never leave that area unchecked.
- Remove the hive lid and check underneath for adult beetles, then place it on a flat piece of ground nearby.
- If the hive has a mat, lift it off and check it. Keep an eye on the combs below to ensure they aren’t being used as an escape route.
- Carefully place the top super on the lid and wait two minutes.
- Lift up the super and look for any beetles trying to hide on the lid.
- Check each super, then finally lift the deep box and check the bottom board. Take the time to search every dark nook and cranny.
- Try to work swiftly and give the adult beetles minimal time to hide.
- Check sugar syrup feeders in the hive for beetles.
- Pollen cakes may house larvae, so examine them closely.
- If your bottom board is attached to the brood box, remove each frame and search for larvae or beetles. Then check the bottom board carefully.
- After completing the lid test, check each frame for the seven symptoms of SHB listed above.
Commonly asked questions
Are small hive beetles easy to detect?
SHB often go undetected when their numbers are low. The adults may leave the hive during the day and return in the evening. Larvae may also go unseen by beekeepers as they develop under cell caps.
At dusk, returning beetles often target recently opened hives more likely to have brood cells laying undefended. These are ideal for female adults to lay their eggs in.
Do SHB harm honey bees?
Small hive beetle larvae make a mess of the hive’s comb by tunneling and burrowing through it. They also harm the colony by feeding on its pollen, honey, and live bee brood.
Is small hive beetle a problem in Africa?
SHB does very little damage to bee colonies in Africa and generally is not considered a hive pest. African honey bees clean out their hive and may swarm, cutting off the parasite’s food supply.
If the SHB population is manageable, African bees use propolis to trap them in a confined space. Their population won’t usually survive more than two months.
What countries SHB found?
These pests have made their home in many countries outside of Africa, including the United States, Canada, Australia, Italy, Cuba, and Mexico. They are not currently in New Zealand or the United Kingdom.
Fast facts about SHB
- The adult beetles are blackish brown and measure 0.2″ (5mm) long.
- They have six legs, two clubbed antennae, and separation between their abdomen and thorax.
- Adult bugs can fly several miles, which makes controlling their spread more difficult.
- Their scientific name for these parasites is Aethina tumida.
- Large infestations are often discovered near honey houses.
- Heavy infestations may cause hive abandonment by the bees.
Small hive beetles are a significant problem for beekeepers in many parts of the world. Their symptoms are hard to identify in small numbers, which allows these critters to build their numbers unnoticed.
Understanding what to look for in hives with SHB is essential knowledge for any beekeeper. Although infested hives may not be saved, early detection will help stop the spread. Speedy removal of small hive beetle in large apiaries may help avoid substantial financial losses.
Image attribution: “Courtesy The Animal and Plant Health Agency (APHA), Crown Copyright”. Sourced from BeeBase Gallery.