Small hive beetle
Damage to bee colonies only occurs when there is a mass reproduction of the beetles in the colony. At present, it is not yet clear what triggers mass reproduction of the beetles. In particular, weak colonies, but also colonies with insufficient hygienic behavior seem to favor the multiplication.
In its area of origin (sub-Saharan Africa), the small hive beetle is considered a harmless co-inhabitant in honey bee colonies, which can be kept well in check by the local honey bees. Around the turn of the millennium, it was introduced to other continents (North America in 1996, Australia in 2002). Since then, there has been further spread to many countries, so that it has now been detected on all continents where the Western honeybee occurs. In 2014, it was first detected in southern Italy, and currently there has been no further spread within Europe. The beetle could cause great damage in Europe, as honey bees native to Europe are not adapted to this pest.
The adult beetles are 5 to 7 mm long and 2.5 to 3.5 mm wide (one-third the size of a worker bee). After hatching from the pupa, the beetle is initially reddish in color and becomes progressively brownish black. The head, thorax and abdomen are clearly separated. The beetle has characteristic club-shaped antennae and tapering corners of the neck shield. The coverts are shorter than the abdomen and therefore the end of the abdomen is visible.
The larva grows up to 12 mm long, is creamy white, and at first glance looks similar to a wax moth larva. However, it can be distinguished from it by the absence of abdominal legs, the presence of three long pairs of forelegs, bristles arranged in double rows on the back, and two long spines at the posterior end.
The eggs are whitish and slightly smaller than bee eggs; they are laid by the females in a protected manner (e.g. in wooden crevices in the hive or directly in the brood cells of the bees).
Pupation takes place in the soil around the bee colony. The duration of development to the adult is highly dependent on temperature and humidity, with a moist, warm environment accelerating development. All stages are sensitive to frost. The adult beetles can overwinter in the winter cluster of the colony. Especially in weak colonies and with insufficient hygienic behavior of the bees, the small hive beetle can multiply en masse in the bee colony.
When working on the colony, always pay attention to possible beetle infestation. We recommend the following procedure for each beekeeping inspection of the colonies:
- When removing the cover, quickly look into the colony to detect any beetles scurrying away (the beetles are shy of light and like to hide in cracks).
- When removing frames, watch out for beetles scurrying downwards. Place the removed frames on a smooth surface (e.g. upside down lid).
- When putting back the frames, check the base for wandering beetles.
- When inspecting the combs, also pay attention to all stages of the small hive beetle (eggs, larvae, beetles) and possible symptoms (feeding traces, slime). Also look into the corners of the hive and the floor, as well as the cracks under the ears of the frames
- If you find any suspicious eggs, larvae or adult beetles, first secure them in a tightly sealed container. To kill them, the pests can be frozen overnight or soaked in 70% undenatured alcohol
Any suspicion of the presence of the small hive beetle must be reported to the competent district administrative authority (Bezirkshauptmannschaft, Magistrat). The suspected eggs, larvae or beetles are sent to the official testing laboratory (National Reference Laboratory for Bee Diseases, AGES). The determination of larvae and adult beetles is based on morphological characteristics. In addition, detection by PCR is possible. Eggs can only be identified by PCR.
Sample submission: Suspect eggs, larvae or adult beetles in a tightly sealable container. The shipment may only take place in the killed state. For this purpose, the pests can be frozen overnight or placed in 70% undenatured alcohol.
DI Hemma Köglberger
- +43 50 555-33127
Last updated: 22.02.2022