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•Varroamites are a key threat to honey bee colonies.•Genetic resources shed light on Varroabiology and interactions with their hosts.•Work describing reproductive cues and host finding shows mite vulnerabilities.•Varroaand honey bees carry shared and unique microbes.•Novel rearing and delivery methods are needed to understand and control mites.

Experiments were conducted to examine how several key factors affect population growth of the small hive beetle, Aethina tumida Murray (Coleoptera: Nitidulidae). Laboratory experiments were conducted to examine effects of food quantity and temperature on reproduction of cohorts of young A. tumida adults (1:1 sex ratio) housed in experimental arenas. Daily numbers and total mass of larvae exiting arenas were highly variable within treatment. Either one or two cohorts of larvae were observed exiting the arenas. Food quantity, either 10 g or 20 g, did not significantly affect the number of larvae exiting arenas at 32°C, but did at 28°C; arenas provided 20 g food produced significantly more larvae than arenas provided 10 g. Temperature did not affect the total mass of larvae provided 10 g food, but did affect larval mass provided 20 g; beetles kept at 28°C produced more larval mass than at 32°C. Field experiments were conducted to examine A. tumida reproductive success in full strength bee colonies. Beetles were introduced into hives as egg-infested frames and as adults, and some bee colonies were artificially weakened through removal of sealed brood. Efforts were unsuccessful; no larvae were observed exiting from, or during the inspection of, any hives. Possible reasons for these results are discussed. The variability observed in A. tumida reproduction even in controlled laboratory conditions and the difficulty in causing beetle infestations in field experiments involving full colonies suggest that accurately forecasting the A. tumida severity in such colonies will be difficult.

Varroa destructor mites (Acari: Varroidae) are harmful ectoparasites of Apis mellifera honey bees. Female foundresses of wax-capped pupal host cells and their daughters feed on host fluids from open wounds on the host's integument. Details of V. destructor mite nutrition are forthcoming, and little is known about the potential physical effects on hosts from mite feeding. Chemical analysis of waste excretions can infer details of animals' nutrition. Here, chemical analysis by high-performance liquid chromatography/mass spectrometry (HPLC-MS/MS) of mite excretions showed that the purine content of V. destructor waste consists of guanine with traces of hypoxanthine. Traces of uric acid and caffeine were also detected. Concentrations of guanine attenuated over time and excretions collected from senescing mites did not contain detectable guanine. Non-reproducing individual female mites maintained in vitro , housed in gelatin capsules and provided a honey bee pupa, deposited an average of nearly 18 excretions daily, mostly on the host's integument rather than on the capsule wall. The weight and volume of excretions suggest mites can consume nearly a microlitre of host fluids each day. Compounded over 10 days, this together with open wounds, could lead to substantial water loss and stress to developing pupae. [ABSTRACT FROM AUTHOR]