Lifecycle of Small Hive Beetle – From Egg To Adult
The lifecycle of a small hive beetle typically takes 3-12 weeks, depending on conditions like temperature, humidity, and available food sources. The stages of development consist of egg, larva, pupa, and adult beetle.
Stage 1: Eggs
Small hive beetles begin their life as an egg. Adult females lay an average of 1000 pearly white eggs throughout their life.
Eggs are often laid in small clusters in hive recesses and crevices or within capped brood cells. Another frequent part of the hive to find eggs is inside or adjacent to pollen cells.
The tiny eggs are 1.4mm long, almost 50% smaller than honey bee eggs. Their size makes them hard to spot, and beekeepers are usually best to look for larvae or adults in their hives.
Humidity impacts the number of eggs that hatch. In states like Alaska and parts of Canada, low humidity and cool temperatures have kept small hive beetle away.
- The eggs will hatch into larvae within 1-6 days, although 2-4 days is common.
- Eggs get laid in irregular clusters within the hive.
- The most prolific female adult beetles can produce up to 2000 eggs in a lifetime.
Stage 2: Larvae
Once small hive beetle eggs hatch, larvae emerge and start damaging the hive. They are almost 0.4” (1cm) in length and have three pairs of prolegs towards the front of their creamy white body. Their back has two rows of small spines.
The larval phase is highly destructive. These pests will burrow through cappings and comb, destroying the colony’s hard work.
Larvae feed on valuable hive resources like honey, pollen, and honey bee eggs. During this time, they contaminate the comb by defecating through it. Yeast K. ohmeri is released, fermenting the honey and resulting in a smelly comb with a slimy appearance. Check out our resource on small hive beetle symptoms to learn more.
Towards the end of this stage, a larva will leave the hive to prepare for pupation. Although it will not usually travel further than 6’ (180cm), it can migrate much further. This time is known as the “wandering phase.”
The larva will search for moist soil and prepare for its next development stage. Some prefer to dig directly beneath the hive.
- The larval stage usually lasts 10-16 days, although it may develop for up to a month. Source.
- Food availability and temperature play an essential role in development time during this phase.
- Larvae may delay pupation if the conditions are suitable.
- A larva will usually leave the hive at night to avoid getting detected by predators.
Stage 3: Pupation
Pupation occurs when the larvae metamorphose into an adult beetle. They will burrow 2-8” (5-20cm) under the ground and build a pupation chamber. At this point, they are most vulnerable to attack by birds and other predators.
During pupation, larvae transform from creamy white to brown or black. The adult small hive beetle will take around 2-12 weeks to emerge. However, it may take up to 100 days if the temperature is below 50°F (10°C)
- Pupae require warmth and moisture to develop into an adult.
- Early-stage pupae already have characteristic projections on their abdomen and thorax.
- Late-stage pupae develop a hard exoskeleton.
Stage 4: Adult beetle
When the adult small hive beetle emerges from the soil, it measures around ¼” (7mm) in length. It will have developed a sclerotized (hard) yellowish-brown exoskeleton which eventually becomes brown or black. Male and female adults also have clubbed antennae.
Adults live for up to 6 months if they have a source of honey to feed on. With less nutritious food like old brood comb, they may only live 50 days.
After emerging from the soil, adult beetles search for new hives to infest. They can usually fly up to 4.3 miles (7km) to find a new home. The beetles use their strong sense of smell to detect the odor of adult bees, pollen, and honey (Elzen & Neumann, 2004).
Small hive beetles look for weak hives during spring and summer when the weather is warmer. As the temperature drops in the fall, they prefer thriving hives that provide extra warmth. They can survive through winter if the hive stays warm.
- An adult can live up to 14 days without any food or water.
- Female beetles are more common and are longer and heavier than males.
- Adult beetles can vary significantly in size depending on the conditions and available food supply.
- On day 7, adult beetles reach sexual maturity and begin mating within the hive.
Helpful reading for beekeepers: Discover how to treat SHB before hive infestation.
7 facts about small hive beetles
- Adult beetles fly just before or after dusk to find a new hive.
- Research suggests that adults may use honey bee alarm pheromones to detect a host colony (Elzen & Neumann, 2004).
- Bees are known to create a prison and set up a “guard watch” when they find SHB.
- Beetles trapped in prison may use their antennae to rub a bee’s mandibles to stay nourished. This practice induces vomiting, which the beetles eat. (Ellis, 2005, Ellis & Hepburn, 2006).
- A compound produced by the yeast on small hive beetles is similar to the alarm pheromone given off by honey bees.
- Scientists do not sufficiently understand the mating behavior of SHB.
- Small hive beetle eggs tend to desiccate if the relative humidity drops below 50% and there is air circulation.
Summing up
Understanding the small hive beetle’s life cycle is valuable knowledge for beekeepers. They are cunning pests, so knowing how they develop and their weaknesses will help keep them out of the hive.
Consider also reading how small hive beetles can be prevented from getting into the hive. There are no guarantees, but these strategies will give bees a fighting chance.
Image attribution: “Courtesy The Animal and Plant Health Agency (APHA), Crown Copyright”. Sourced from BeeBase Gallery.