The Impact of Recent Queenloss and Colony Pheno-type on the Removal of Small Hive Beetle ( Aethina tumida Murray) Eggs and Larvae by African Honeybee Colonies ( Apis mellifera capensis Esch.)

The removal of small hive beetle [=SHB] eggs and larvae was studied in queenright and recently queenless Cape honeybee, Apis mellifera capensis, colonies over a range of phenotypes. The overall removal efficiency was not influenced by phenotypes or queenstate, because all introduced eggs and larvae were removed within 24 hours. Queenless colonies removed them merely slower than queenright ones. The latter ones rejected up to 300 larvae within one hour. However, colonies undergoing preparation for absconding did not completely remove SHB offspring, suggesting that removal efficiency was reduced. Since even small and recently queenless colonies effectively removed immature SHB, and no differences in the overall efficiency was found compared to A. m. scutellata we conclude that this defense behavior is well developed in African honeybee

Worldwide Diaspora of Aethina tumida (Coleoptera: Nitidulidae), a Nest Parasite of Honey Bees

Native to sub-Saharan Africa, Aethina tumida Murray (Coleoptera: Nitidulidae) is now an invasive pest of honey bee, Apis mellifera L., colonies in Australia and North America. Knowledge about the introduction(s) of this beetle from Africa into and among the current ranges will elucidate pest populations and invasion pathways and contribute to knowledge of how a parasite expands in new populations. We examined genetic variation in adult beetle samples from the United States, Australia, Canada, and Africa by sequencing a 912-base pair region of the mitochondrial DNA cytochrome c oxidase subunit I gene and screening 10 informative microsatellite loci. One Canadian introduction of small hive beetles can be traced to Australia, whereas the second introduction seems to have come from the United States. Beetles now resident in Australia were of a different African origin than were beetles in North America. North American beetles did not show covariance between two mitochondrial haplotypes and their microsatellite frequencies, suggesting that these beetles have a shared source despite having initial genetic structure within their introduced range. Excellent dispersal of beetles, aided in some cases by migratory beekeeping and the bee trade, seems to lead to panmixis in the introduced populations as well as in Afric

NOTES AND COMMENTS Cryptic low-level reproduction of small hive beetles in honey bee colonies

is native to Africa south of the Sahara and has recently become an invasive species in populations of European derived honey bees, Apis mellifera (Neumann and Elzen, 2004). SHB reproduction can occur in recently abandoned honey bee nests but also in colonies where the bees are still present (Lundie, 1940; Neumann and Elzen, 2004). Furthermore, SHB may also reproduce on fruits (Ellis et al., 2002) or in bumblebee nests (Ambrose et al., 2000). While the adults have comparatively little impact on the honey bee colony, the larvae can cause severe damage to combs (Lundie, 1940), often resulting in the full structural collapse of the nest. SHB reproduction in honey bee colonies is associated with typical signs such as a rotten smell, fermented honey and comb damage (Lundie, 1940). Here we report for the first time on the reproduction of small hive beetles in honey bee colonie

Small hive beetle, Aethina tumida, populations II: Dispersal of small hive beetles

Small hive beetles (= SHB), Aethina tumida, are parasites and scavengers of honeybee colonies and actively disperse for host finding. We investigated the re-infestation levels of SHB-free colonies within ten infested apiaries in South Africa, Australia and the USA. Re-infestation of 95% of the colonies indicates a high SHB exchange between colonies. Colony position and queen status had no influence on colony infestation levels. Spread into apiaries was determined at twelve SHB-free apiaries. While apiaries in Maryland remained un-infested, those in Australia showed high infestation numbers. Apiary density, SHB population levels and ongoing SHB mass reproduction seem to govern SHB infestation of newly installed apiaries. Those located in forested habitats showed higher infestation levels possibly due to the presence of wild/feral colonies. The results elucidate factors influencing SHB dispersal and the role of human-mediated spread, enabling improved control of SHB

Small hive beetle, Aethina tumida, populations II : dispersal of small hive beetles

Small hive beetles (= SHB), Aethina tumida, are parasites and scavengers of honeybee colonies and actively disperse for host finding. We investigated the re-infestation levels of SHB-free colonies within ten infested apiaries in South Africa, Australia and the USA. Re-infestation of 95% of the colonies indicates a high SHB exchange between colonies. Colony position and queen status had no influence on colony infestation levels. Spread into apiaries was determined at twelve SHB-free apiaries. While apiaries in Maryland remained un-infested, those in Australia showed high infestation numbers. Apiary density, SHB population levels and ongoing SHB mass reproduction seem to govern SHB infestation of newly installed apiaries. Those located in forested habitats showed higher infestation levels possibly due to the presence of wild/feral colonies. The results elucidate factors influencing SHB dispersal and the role of human-mediated spread, enabling improved control of SHB

Small hive beetle, Aethina tumida, populations I : infestation levels of honeybee colonies, apiaries and regions

The small hive beetle (SHB) is a parasite and scavenger of honeybee colonies. Here we provide the first comprehensive systematic data on colony infestation levels with adult SHB for 226 colonies at 31 apiaries in South Africa, Australia, Florida and Maryland. Inside colonies, SHB distribution was influenced by the presence of bees with more SHB in the brood nest in the absence of bees. SHB distribution among colonies at an apiary was different from a random distribution but colony phenotypes (number of bees, amount of brood or stores) did not influence infestation levels. Apiaries next to large scale honey extraction facilities (honey houses) showed higher infestation levels and regions with more damage had higher SHB population levels. Consequently, methods of reducing SHB populations, such as the removal of dead colonies and the prevention of SHB reproduction in honey houses, seem to be important for pest management

Susceptibility of small honey bee colonies to invasion by the small hive beetle, Aethina tumida (Coleoptera, Nitidulidae)

Weak and small honey bee colonies are supposed to be more susceptible to infestations by the small hive beetle [Aethina tumida, small hive beetle (SHB)]. To test this, we established 24 nucleus colonies [12 with and 12 without previous SHB removal (= screening)]. Four weeks later, we compared beetle numbers and the occurrence of SHB reproduction to the corresponding full-sized colonies. Full-sized colonies with no screening were infested with significantly more SHBs than all other groups (mean ± standard deviation = 46.9 ± 26.7). Regardless of this, none of the full-sized colonies showed damage or evidence of SHB reproduction. In contrast, five nucleus colonies collapsed and SHB larvae were found in an additional seven colonies. Our study demonstrates that SHB infestation levels which are harmless to full-sized colonies may have a negative impact on small nucleus colonies

Small hive beetle, Aethina tumida, populations I: Infestation levels of honeybee colonies, apiaries and regions

The small hive beetle (SHB) is a parasite and scavenger of honeybee colonies. Here we provide the first comprehensive systematic data on colony infestation levels with adult SHB for 226 colonies at 31 apiaries in South Africa, Australia, Florida and Maryland. Inside colonies, SHB distribution was influenced by the presence of bees with more SHB in the brood nest in the absence of bees. SHB distribution among colonies at an apiary was different from a random distribution but colony phenotypes (number of bees, amount of brood or stores) did not influence infestation levels. Apiaries next to large scale honey extraction facilities (honey houses) showed higher infestation levels and regions with more damage had higher SHB population levels. Consequently, methods of reducing SHB populations, such as the removal of dead colonies and the prevention of SHB reproduction in honey houses, seem to be important for pest management