Aethina tumida, commonly known as the small hive beetle (SHB), is a beekeeping pest. It is native to sub-Saharan Africa, but has spread to many other regions, including North America, Australia, and the Philippines. The small hive beetle primarily lives within the beehive and feeds on pollen, honey, and dead bees. The colonization can cause severe damage to honeycomb, stored honey, and pollen. Beetle larvae may tunnel through combs of honey, feeding and defecating, causing discoloration and fermentation of the honey. If a beetle infestation is abundant and concentrated, they may cause bees to abandon their hive. Small hive beetles have shown unique behavior associated with pheromones. They can sense the honeybee's alarm pheromone, which is primarily released by the host to inform the host guards about the presence of invaders. This fitness advantage improves their ability to quickly locate and colonize the honeybee hives. The host has evolved some strategies to cope with the colony damage, such as imprisonment of the invader, patrolling, and removal of beetle's eggs. Small hive beetles can cause significant economic loss on bee colony, stored honey, and package bee production. Biological control method includes uses of fungi and fire ants. Cultural control focuses on the hygienic practice of beekeeper. Chemical control strategy includes uses of carbon disulfide, para-dichlorobenzene, and some chemical products on the market.
Distribution The small hive beetle was first discovered in the United States in 1996 and has now spread to 27 U.S. states, including Hawaii. An infestation by small hive beetle was triggered in 2015 in British Columbia which led to a temporary quarantine. In Mexico, the small hive beetle has become established in at least eight states. Infestation levels are especially high in tropical areas such as the Yucatán. The small hive beetle was first detected in Belize in 2016 in the Corozal District and was reported in Honduras in 2024 The small hive beetle has also spread to Australia in areas of Richmond, New South Wales, Queensland, and New South Wales. It was not found in Northern Territory and has no longer been a notifiable pest in Victoria and South Australia. In Western Australia, it is restricted to the Kimberly region. It is possible that the import of package bees, honeybee or bumblebee colonies, queens, hive equipment, or even soil constituted the potential invasion pathway of the small hive beetle; however, at the current state of evidence it is still unclear how small hive beetles actually reached Australia. The small hive beetle has now reached southern Mindanao in the Philippines. It might lead to a spread through the country if hives and bees are moved to other areas. Small hive beetle was first detected in Calabria, southern Italy in September 2014. It is currently confined to the provinces of Reggio Calabria and part of Vibo Valentia, where it has now become naturalized. In 2014 and 2019, outbreaks of infestation occurred in eastern Sicily.
Habitat Females lay eggs within the bee brood and larvae would hatch inside. Pupation happens under the soil. The adults primarily live within the host hive and seek for food from the hosts. Adults can overwinter with the bee population in colder climates.
Food resources Small hive beetles are insectivores, and they can be fed on both animal and plant diets. Animal diets include the bee eggs, host body fluids, and dead bees. Plant diets include fruit, nectar, and pollen. Adults and larvae are fed by the same food.
Description Small hive beetles are categorized as small insects with length around 5-7mm and width around 2.5-3.5mm. Sexual dimorphism is observed since females are usually longer and heavier than male. The size of the beetles may vary based on environmental factors such as diet, temperature, and humidity. For their body structure, there are three pairs of walking legs, two antennae, and two pairs of wings. Their body is bilaterally symmetrical. They have a wide range of body coloration, from orange-brown to dark brown or black. This species is ectothermic, which means they rely on external heat sources to adjust body temperature. Younger small hive beetles have a very distinguishable appearance than adults. The beetle eggs are elongated with a white color. The beetle larvae have reduced white color with a segmented body shape. They have three pairs of legs behind the head. When the exoskeleton develops, the pupae turn to brown color which looks more similar to adults.
Parental care
Oviposition Small hive beetles reproduce sexually up to 5 generations each year and they are polygynandrous, meaning that both males and females mate with multiple partners. The eggs are fertilized externally and are laid in clusters. Females can oviposit at least 1000 and up to 2000 eggs in her entire life. Females prefer to lay eggs directly onto their food sources and can also lay eggs in crevices within the beehive to improve the offspring survival rate via granted food resources. It was found that female can lay eggs on bee pupae when the colony is mainly occupied by the beetle. During the winter time, the beetles prefer strong hives for more resources to keep their body temperature. On the contrary, they prefer weaker hives to invade and reproduce during the summertime.
Social behavior
Reproduction seasonality The peak of reproduction period varies in different places. Most small hive beetle populations reach the highest density during the summer and early autumn season with high temperature. Some populations show preference for the rainy season while others prefer the dry season.
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