Honey Bee Medicine for the Veterinary Practitioner. Группа авторов

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Honey Bee Medicine for the Veterinary Practitioner - Группа авторов


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(2017b) Short‐lived; 2–3 yr without miticides Rosenkranz et al. (2010) Annual survival High survivorship 84% (established) 20% (founder) Seeley (2017b) Low survivorship (0–50%) Ellis et al. (2010) Cavity size of home Small cavity; 45 l (30–60 l) Seeley and Morse (1976) Large cavity; 120–160 l Loftus et al. (2016) Swarming frequency 87% annual queen turnover in established colonies Seeley (2017b) Swarming suppressed, so low queen turnover Oliver (2015) Propolis barrier Complete barrier “propolis envelope” Seeley and Morse (1976) Incomplete barrier smooth hive walls Hodges et al. (2018) Colony spacing Colonies far apart (~1 km) Seeley and Smith (2015) Radcliffe and Seeley (2018) Colonies close together (~1 km) Root and Root (1908) Virulence level vertical transmission of mite‐vectored pathogens, via swarming Seeley and Smith (2015) Virulence favored by horizontal transmission of mite‐vectored pathogens, via drifting/robbing Seeley and Smith (2015) Nest insulation Thick‐walled (20 cm/8‐in.) well insulated tree cavity Seeley and Morse (1976) Thin‐walled (2.5 cm/1‐in.) poorly insulated Langstroth Root and Root (1908) Immune Function Strong social immunity, Immune genes downregulated Simone et al. (2009) Weak social immunity, Immune genes upregulated Borba et al. (2015)

      All honey bee populations that have survived for more than a decade without miticide treatments share a common feature: their colonies are small (Locke 2016). Small colony size relates directly to the dynamics of brood development and swarming. Having relatively few brood has two significant impacts on mite reproduction. First, since Varroa mites only reproduce within the cells of sealed (pupal stage) brood, the reproduction of these mites is hampered by the relatively small brood nests of wild colonies. Second, a small nest cavity size shortens the time before the sealed brood fills a colony's brood nest, and this brood nest congestion is one of the primary cues for swarms and afterswarms (Winston 1980). When colonies living in large hives (two deep hive bodies plus two honey supers) were compared to colonies living in small hives (just one deep hive body, to mimic the nest cavity size in nature), it was found that the small‐hive colonies had reduced mite loads and improved colony survival, as a result of more frequent swarming and lowered Varroa infestations (Loftus et al. 2016).

      Wall Thickness and Thermoregulation

      Seeley and Morse (1976) reported that the average wall thickness of natural nest cavities is approximately 20 cm (~8 in.). The wall thickness of a standard Langstroth hive is just 1.9 cm (0.75 in.), hence some 10 times thinner than the nest cavity wall of a bee tree. The reduced wall thickness in Langstroth hives creates a large reduction in nest insulation, possibly resulting in adverse effects on colony energetics. Large temperature fluctuations inside a hive exacerbate colony stress by increasing the demands on colony nutrition and hydration (more nectar and water foraging trips), by impairing a colony's ability to maintain thermal homeostasis (more fanning and “bearding” when it is hot, and more metabolic heat production when it is cold), and by hastening entry into a winter cluster – all of which increase the physiological demands on the colony (Mitchell 2016).

Schematic illustration of the comparison of the structure and organization of a honey bee nest as found in a bee tree (left) and a standard Langstroth hive made up of two deep hive bodies (right). Photos depict a research station beside the Shindagin Hollow State Forest in upstate New York.
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