The small hive beetle, Aethina tumida Murray (Coleoptera: Nitidulidae), belongs to a family of beetles known as sap beetles. As an agricultural pest they feed upon damaged, overripe fruits and vegetables, such as strawberries, corn, melons, tomatoes, and raspberries. The small hive beetle is a major parasite of honey bee hives worldwide. The beetle lives in the honey bee hive and feeds on honey, pollen, and honey bee brood. Fruit volatiles collected from overripe fruit provide for an effective attractant for both sexes of the small hive beetle. A laboratory trapping assay was performed using ripe fruit and a fruit-semiochemical attractant blend containing ethanol, ethyl butyrate, acetic acid, ethyl acetate, and acetaldehyde. Results indicated that the synthetic fruit blends captured beetles at the same rate as the cut fruit. The blend with the highest concentration had significantly more beetles captured. The key to an effective trapping system is a good attractant. The isolated fruit volatiles show promise as a possible attractant for control and monitoring of small hive beetle.
The spread of invasive species often follows a jump-dispersal pattern. While jumps are typically fostered by humans, local dispersal can occur due to the specific traits of a species, which are often poorly understood. This holds true for small hive beetles (Aethina tumida), which are parasites of social bee colonies native to sub-Saharan Africa. They have become a widespread invasive species. In 2017, a mark-release-recapture experiment was conducted in six replicates (A–F) using laboratory reared, dye-fed adults (N = 15,690). Honey bee colonies were used to attract flying small hive beetles at fixed spatial intervals from a central release point. Small hive beetles were recaptured (N = 770) at a maximum distance of 3.2 km after 24 h and 12 km after 1 week. Most small hive beetles were collected closest to the release point at 0 m (76%, replicate A) and 50 m (52%, replicates B to F). Temperature and wind deviation had significant effects on dispersal, with more small hive beetles being recaptured when temperatures were high (GLMM: slope = 0.99, SE = 0.17, Z = 5.72, P < 0.001) and confirming the role of wind for odour modulated dispersal of flying insects (GLMM: slope = − 0.39, SE = 0.14, Z = − 2.90, P = 0.004). Our findings show that the small hive beetles is capable of long-distance flights, and highlights the need to understand species specific traits to be considered for monitoring and mitigation efforts regarding invasive alien species.
Beekeepers need new registered products to control the small hive beetle (SHB), Aethina tumida, a significant pest of western honey bee (Apis mellifera) colonies. Few approved chemical controls exist, and there is no standardized system for screening compounds against SHBs. We outline a detailed method for an acute toxicity bioassay that delivers compounds via pollen. We provide a detailed method for a field trial that delivers treated pollen in traps made from modified compact disc cases. We applied both methods in proof-of-concept experiments to assess acetamiprid as a SHB control agent. Using the laboratory bioassay, we found acetamiprid ( = 20.5 µg/g) to be more toxic to SHBs than coumaphos was ( = 1250 µg/g), yet less toxic to SHBs than fipronil was ( = 1.78 µg/g). In our field trial, colonies treated with acetamiprid and fipronil significantly reduced (p < 0.001) live SHB populations over those of control colonies. Traps containing acetamiprid retained significantly higher (p < 0.001) numbers of dead SHBs than did traps containing fipronil. We outline the first detailed methods to assess the toxicity of compounds delivered in pollen for adult SHB control. Our proof-of-concept experiments showed acetamiprid to be a promising control agent for SHBs.
The maize weevil Sitophilus zeamais (Motschulsky) (Coleoptera: Curculionidae) is an important pest of stored grains, predominantly maize (Zea mays L.), wheat (Triticum L. spp.), rice (Oryza L. spp.), and sorghum (Sorghum bicolor [L.] Moench) (all Poaceae). Weevil infestations occur in the field and weevils are carried to the storage facility after harvest. Infestation also occurs in the grain storage facility. There is no effective field or storage trapping system for control. They are commonly parasitized by Pteromalidae Dalman (Hymenoptera: Chalcidoidea) spp. parasitoids in the Tropics; however, there is no biocontrol use of these Hymenoptera. Therefore, pesticide application and the development of resistant grain are the current control strategies; although, studies have indicated that odors associated with the grain upon which the weevils feed, mate, and oviposit are attractive to the weevil. Host plant produced volatiles and their associations with the maize weevil have not been investigated fully. To better understand the weevil's attraction to crop plants, a study was initiated to investigate the weevil's preference for immature host plants. Weevils that had been reared on 4 types of grain for several generations were presented immature plants of all 4 types of grains in choice tests to determine if they prefer grains of the host plant on which they had been reared. This research demonstrated that immature rice plants have the greatest attraction, and that previous feeding did not influence the weevil's host plant attraction. The isolation of key rice plant semiochemicals will be the focus in the development of an attractant for S. zeamais and may also prove effective for the control of Sitophilus oryzae (L.) (Coleoptera: Curculionidae).
12 October 2022 in Journal of Apicultural Research
Research to investigate the small hive beetle, Aethina tumida, and its effects on the honey bee requires a consistent supply of healthy beetles. This protocol describes an effective rearing method for the small hive beetle using commercially available pollen patties and equipment that can easily be constructed from local sources. In this protocol, a method is described that allows for many thousands of healthy beetles to be reared weekly in a confined space. This knowledge is a crucial step for the advancement of research studies and the development of management protocols for the small hive beetle.