-Monitoring physical variables associated with honeybee colonies, including weight, temperature, humidity, respiratory gases, vibration, sound, and forager traffic, in a continuous manner is becoming feasible for most researchers as the cost and size of electronic sensors decrease while their precision and capacity increase. Researchers have taken different approaches to collecting and analyzing the resulting datasets, with a view toward extracting information on colony behavior and phenology. The objective of this review is to examine critically the different kinds of data and data analyses, providing researchers with better-informed options for obtaining information on colony phenology in the field without disturbing the hive, and for combining information from different kinds of sensors to obtain a more complete picture of colony status. Wireless sensor networks and powering sensors are briefly discussed.continuous hive weight / colony temperature / colony humidity / forager traffic / hive vibration

SummaryPollination by honey bees plays a key role in the functioning of ecosystems and optimisation of agricultural yields. Severe honey bee colony losses worldwide have raised concerns about the sustainability of these pollination services. In many cases, bee mortality appears to be the product of many interacting factors, but there is a growing consensus that the ectoparasitic mite Varroa destructor plays the role of the major predisposing liability. We argue that the fight against this mite should be a priority for future honey bee health research. We highlight the lack of efficient control methods currently available against the parasite and discuss the need for new approaches. Gaps in our knowledge of the biology and epidemiology of the mite are identified and a research road map towards sustainable control is drawn. Innovative and challenging approaches are suggested in order to stimulate research efforts and ensure that honey bees will be able to sustainably fulfil their role in the ecosystem. Varroa destructor: alternativas para su control sostenible ResumenLa polinización por las abejas melíferas tiene una importante relevancia en el funcionamiento de los ecosistemas y en la optimización de los rendimientos agrícolas. Se ha expresado la preocupación acerca de la sostenibilidad de estos servicios de polinización, debido a las graves pérdidas de colonias de abejas melíferas a nivel mundial. En varios de estos casos, la pérdida de estas abejas parece ser el resultado de la interacción de muchos factores, existiendo un creciente consenso en que el ácaro ectoparásito Varroa destructor desempeña alguna

There is increasing worldwide concern about the impacts of pesticide residues on honey bees and bee colony survival, but how sublethal effects of pesticides on bees might cause colony failure remains highly controversial, with field data giving very mixed results. To explore how trace levels of the neonicotinoid pesticide imidacloprid impacted colony foraging performance, we equipped bees with RFID tags that allowed us to track their lifetime flight behavior. One group of bees was exposed to a trace concentration (5 μg/kg, ppb) of imidacloprid in sugar syrup while in the larval stage. The imidacloprid residues caused bees to start foraging when younger as adults and perform fewer orientation flights, and reduced their lifetime foraging flights by 28%. The magnitude of the effects of a trace imidacloprid concentration delivered only during larval stage highlights the severity of pesticide residues for bee foraging performance. Our data suggest that neonicotinoids could impact colony function by imbalancing the normal age based division of labor in a colony and reducing foraging efficiency. Understanding this mechanism will help the development of interventions to safeguard bee colony health.

-Continuous weight and temperature data were collected for honey bee hives in two locations in Arizona, and those data were evaluated with respect to separate measurements of hive phenology to develop methods for noninvasive hive monitoring. Weight and temperature data were divided into the 25-h running average and the daily within-day changes, or Bdetrended^data. Data on adult bee and brood masses from hive evaluations were regressed on the amplitudes of sine curves fit to the detrended data. Weight data amplitudes were significantly correlated with adult bee populations during nectar flows, and temperature amplitudes were found inversely correlated with the log of colony brood weight. The relationships were validated using independent datasets. In addition, the effects of an adult bee kill on hive weight data were contrasted with published data on weight changes during swarming. Continuous data were found to be rich sources of information about colony health and activity.continuous hive weight / continuous hive temperature / bee colony phenology / adult bee mass / brood production

Imidacloprid is a neonicotinoid pesticide heavily used by the agricultural industry and shown to have negative impacts on honey bees above certain concentrations. We evaluated the effects of different imidacloprid concentrations in sugar syrup using cage and field studies, and across different environments. Honey bee colonies fed sublethal concentrations of imidicloprid (0, 5, 20 and 100 ppb) over 6 weeks in field trials at a desert site (Arizona), a site near intensive agriculture (Arkansas) and a site with little nearby agriculture but abundant natural forage (Mississippi) were monitored with respect to colony metrics, such as adult bee and brood population sizes, as well as pesticide residues. Hive weight and internal hive temperature were monitored continuously over two trials in Arizona. Colonies fed 100 ppb imidacloprid in Arizona had significantly lower adult bee populations, brood surface areas and average frame weights, and reduced temperature control, compared to colonies in one or more of the other treatment groups, and consumption rates of those colonies were lower compared to other colonies in Arizona and Arkansas, although no differences in capped brood or average frame weight were observed among treatments in Arkansas. At the Mississippi site, also rich in alternative forage, colonies fed 5 ppb imidacloprid had less capped brood than control colonies, but contamination of control colonies was detected. In contrast, significantly higher daily hive weight variability among colonies fed 5 ppb imidacloprid in Arizona suggested greater foraging activity during a nectar flow post treatment, than any other treatment group. Imidacloprid concentrations in stored honey corresponded well with the respective syrup concentrations fed to the colonies and remained stable within the hive for at least 7 months after the end of treatment.