•Land use in the Northern Great Plains of the US has led to reduced bee forage.•We examine the impact of land use on honey bee colony survival and productivity.•The area of uncultivated forage land ...positively influenced annual apiary survival.•Plants utilized by honey bee colonies for pollen were primarily volunteer species.•Potential for improving honey bee habitat and management of lands are discussed.
The Northern Great Plains region of the US annually hosts a large portion of commercially managed U.S. honey bee colonies each summer. Changing land use patterns over the last several decades have contributed to declines in the availability of bee forage across the region, and the future sustainability of the region to support honey bee colonies is unclear. We examined the influence of varying land use on the survivorship and productivity of honey bee colonies located in six apiaries within the Northern Great Plains state of North Dakota, an area of intensive agriculture and high density of beekeeping operations. Land use surrounding the apiaries was quantified over three years, 2010–2012, and survival and productivity of honey bee colonies were determined in response to the amount of bee forage land within a 3.2-km radius of each apiary. The area of uncultivated forage land (including pasture, USDA conservation program fields, fallow land, flowering woody plants, grassland, hay land, and roadside ditches) exerted a positive impact on annual apiary survival and honey production. Taxonomic diversity of bee-collected pollen and pesticide residues contained therein varied seasonally among apiaries, but overall were not correlated to large-scale land use patterns or survival and honey production. The predominant flowering plants utilized by honey bee colonies for pollen were volunteer species present in unmanaged (for honey bees), and often ephemeral, lands; thus placing honey bee colonies in a precarious situation for acquiring forage and nutrients over the entire growing season. We discuss the implications for land management, conservation, and beekeeper site selection in the Northern Great Plains to adequately support honey bee colonies and insure long term security for pollinator-dependent crops across the entire country.
Small hive beetles (SHBs) are generalists native to sub-Saharan Africa and reproduce in association with honeybees, bumblebees, stingless bees, fruits and meat. The SHB has recently become an ...invasive species, and introductions have been recorded from America, Australia, Europe and Asia since 1996. While SHBs are usually considered a minor pest in Africa, they can cause significant damage to social bee colonies in their new ranges. Potential reasons for differential impact include differences in bee behaviour, climate and release from natural enemies. Here, we provide an overview on biology, distribution, pest status, diagnosis, control and prevention to foster adequate mitigation and stimulate future research. SHBs have become a global threat to both apiculture and wild bee populations, but our knowledge of this pest is still limited, creating demand for more research in all areas of its biology.
Managed honey bee colony losses are of concern in the USA and globally. This survey, which documents the rate of colony loss in the USA during the 2015-2016 season, is the tenth report of winter ...losses, and the fifth of summer and annual losses. Our results summarize the responses of 5725 valid survey respondents, who collectively managed 427,652 colonies on 1 October 2015, an estimated 16.1% of all managed colonies in the USA. Responding beekeepers reported a total annual colony loss of 40.5% 95% CI 39.8-41.1% between 1 April 2015 and 1 April 2016. Total winter colony loss was 26.9% 95% CI 26.4-27.4% while total summer colony loss was 23.6% 95% CI 23.0-24.1%, making this the third consecutive year when summer losses have approximated to winter losses. Across all operation types, 32.3% of responding beekeepers reported no winter losses. Whilst the loss rate in the winter of 2015-2016 was amongst the lowest winter losses recorded over the ten years this survey has been conducted, 59.0% (n = 3378) of responding beekeepers had higher losses than they deemed acceptable.
For the past six years in which overwintering mortality of honey bee colonies has been surveyed in the USA, estimates of colony loss have fluctuated around one-third of the national population. Here ...we report on the losses for the 2012-2013 seasons. We collected data from 6,482 US beekeepers (6,114 backyard, 233 sideline, and 135 commercial beekeepers) to document overwintering mortality rates of honey bee colonies for the USA. Responding beekeepers reported a total 30.6% (95% CI: 30.16-31.13%) loss of US colonies over the winter, with each beekeeper losing on average 44.8% (95% CI: 43.88-45.66%) of their colonies. Total winter losses varied across states (range: 11.0% to 54.7%). The self-reported level of acceptable winter loss was 14.6%, and 73.2% of the respondents had mortality rates greater than this level. The leading self-identified causes of overwintering mortality were different according to the operation type; backyard beekeepers generally self-identified "manageable" factors (e.g., starvation, weak colony in the fall), while commercial beekeepers generally identified non-manageable factors (e.g., queen failure, pesticides) as the main cause of losses. For the first time in this series of surveys, we estimated mortality during the summer (total loss = 25.3% (95% CI: 24.80-25.74%), average loss = 12.5% (95% CI: 11.92-13.06%)). The entire 12-months period between April 2012 and April 2013 yielded a total loss of 45.2% (95% CI: 44.58-45.75%), and an average loss of 49.4% (95% CI: 48.46-50.43%). While we found that commercial beekeepers lost fewer colonies than backyard beekeepers in the winter (30.2% (95% CI: 26.54-33.93% vs 45.4% (44.46-46.32%) respectively), the situation was reversed in the summer where commercial beekeepers reported higher average losses than backyard beekeepers (21.6% (95% CI: 18.4-24.79%) vs 12.1% (11.46-12.65%)). These findings demonstrate the ongoing difficulties of US beekeepers in maintaining overall colony heath and survival.
Small hive beetles, Aethina tumida, are parasites and scavengers of honey bee and other social bee colonies native to sub-Saharan Africa, where they are a minor pest only. In contrast, the beetles ...can be harmful parasites of European honey bee subspecies. Very rapidly after A. tumida established populations outside of its endemic range, the devastating effect of this beetle under suitable climatic conditions prompted an active research effort to better understand and control this invasive species. Over a decade, A. tumida has spread almost over the entire USA and across the east coast of Australia. Although comparatively few researchers have worked with this organism, a diversity of research methods emerged using sets of diverse techniques to achieve the same goal. The diversity of methods made the results difficult to compare, thus hindering our understanding of this parasite. Here, we provide easy-to-use protocols for the collection, identification, diagnosis, rearing, and for experimental essays of A. tumida. We hope that these methods will be embraced as standards by the community when designing and performing research on A. tumida.
Nosema ceranae, a microsporidian parasite originally described from Apis cerana, has been found to infect Apis melllifera and is highly pathogenic to its new host. In the present study, data on the ...ultrastructure of N. ceranae, presence of N. ceranae-specific nucleic acid in host tissues, and phylogenetic relationships with other microsporidia species are described. The ultrastructural features indicate that N. ceranae possesses all of the characteristics of the genus Nosema. Spores of N. ceranae measured approximately 4.4 x 2.2 μm on fresh smears. The number of coils of the polar filament inside spores was 18-21. Polymerase chain reaction (PCR) signals specific for N. ceranae were detected not only in the primary infection site, the midgut, but also in the tissues of hypopharyngeal glands, salivary glands, Malpighian tubules, and fat body. The detection rate and intensity of PCR signals in the fat body were relatively low compared with other examined tissues. Maximum parsimony analysis of the small subunit rRNA gene sequences showed that N. ceranae appeared to be more closely related to the wasp parasite, Nosema vespula, than to N. apis, a parasite infecting the same host.
Estimates of winter loss for managed honey bee (Apis mellifera) colonies are an important measure of honey bee health and productivity. We used data from 5,500 US beekeepers (5,244 backyard, 189 ...sideline and 67 commercial beekeepers) who responded to the April 2012 Bee Informed Partnership Winter Colony Loss Survey and calculated loss as the difference in the number of colonies between October 1, 2011 and April 1, 2012, adjusting for increases and decreases over that period. In the US, the total colony loss was 22.5% for the 2011-12 winter; 45.1% (n = 2,482) of respondents reported no colony loss. Total loss during 2011-12 was substantially lower than loss during 2010-11 (29.9%). Of the 4,484 respondents who kept bees in 2010-11 and 2011-12, 72.0% reported that the loss during 2011-12 was smaller or similar to the loss during 2010-11. There was substantial variation in total loss by state (range 6.2% to 47.7%). The average loss per beekeeping operation was 25.4%, but the average loss was not significantly different by operation type (backyard, sideline, commercial). The average self-reported acceptable loss per respondent was 13.7%; 46.8% (n = 2,259) of respondents experienced winter colony losses in excess of the average acceptable loss. Of beekeepers who reported losing at least one colony during 2011-12, the leading self-identified causes of mortality were weak condition in the fall and queen failure. Respondents who indicated poor wintering conditions, CCD, or pesticides as a leading cause of mortality suffered a higher average loss when compared to beekeepers who did not list these as potential causes.
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.
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.