VW foundation - Sentinel Beehive
Real-time Monitoring of the 3D-Thermal Distribution
The honeybee is of paramount importance to humans in both agricultural and ecological settings. During the lasts decades honeybee colonies have suffered from a new, still not understood, phenomenon, called Colony Collapse Disorder (CCD). It is believed that CCD stems from a complex set of interacting stresses, to name a few of them - nutritional stress due to loss of appropriate forage distribution in time, environmental pollution, infections by pathogenic microbes or viruses, accelerated by the invasion of the parasitic mite Varroa destructor (Figure 1a).
A bee-colony must be treated as a superorganism, where the existence and the lifespan of each given individual rely on a myriad of coordinated inter-individual interactions, governed by endothermy. This is realised via physiological heat generation and regulation of body temperature by metabolic means of adult honeybees. Therefore, each stage of the living cycle of the bee-colony must have its optimal and characteristic 3-dimensional temperature distribution (3D-TD).
Our working hypothesis assumes that there is an optimal 3D-TD for each phase of the life-cycle of the bee-colony. Knowing this 3D-TD will allow recognizing and distinguishing between various harmful occurrences at the bee-colony. Re-establishment of the optimal 3D-TD or its manipulation towards environmental–friendly extermination of the Varroa-mites will be than a straight forward procedure (Figure 1b).
Herewith, we propose to use the perturbation (deviation from natural 3D-TD) of the social thermal homeostasis in honeybee nests as a response of the bee-colony superorganism on external stressors, such as parasitic mites and/or viral invasions. The sensing procedure must be inherently non-invasive: only if the bee-colony studied follows its natural living sequence, will the reaction on external stressor be authentic. That means the size of the colony, forage and breeding activities must be as possible natural.
During the Sentinel Beehive-project, supported by VW-Foundation, we are using the dependence of the ohmic resistance of decorated tosylate-type ionic liquids (Figure 1c) on the sample temperature as a sensing tool. Such ionic liquids demonstrate sustainable and well reproducible temperature sensitivity of 50mK, allowing to create sensing elements by ink-jet printing technology.