Underground Animal Tracking & Mapping in 3D

Wildlife tracking using wireless sensor networks has garnered a great deal of attention and research, since the seminal ZebraNet project monitored zebras with mobile nodes in 2002. However, research to date has concentrated on monitoring animals when they are above ground. It is currently impossible to automatically monitor animals whilst they are underground. The main reason for this is that radio waves are severely attenuated by layers of soil, to the point of being unusable. There is a strong need for a system that can localize burrowing animals when they are within their dens or tunnels, in order to better understand their behaviour and habits. A prime example of this is the European badger - badgers are a protected species in the UK, yet are subject to widespread culling due to their possible link to bovine TB. By monitoring internal sett conditions and animal interactions underground, a better understanding of infection could potentially be obtained.

To tackle these issues, I propose the use of low frequency magnetic fields (i.e. the principle of magneto-induction, MI), which are able to penetrate soil without attenuation, to provide ultra-low power three dimensional localization of wild animals within their burrows. Data from tracking collars will be forwarded by conventional high frequency radio links when the animal is above ground, meaning that the animal does not need to be recaptured to obtain the stored information. By mapping animal movements over time, the subterranean tunnel architecture itself will be determined, something which can currently only be obtained, destructively, through excavation. Sensors within the tunnel will monitor gas concentrations and temperature gradients, which will help to explain how animals achieve suitable ventilation underground and maintain body temperature. To investigate animal behaviour, tracking collars will be equipped with miniature sensors, such as accelerometers and magnetometers, which will record motion and energetics. To reduce data volumes, tracking collars will automatically characterize animal behaviour primitives, such as walking or sleeping. To further increase the rate of "learning" this information, tracking collars will share motion features, forming a distributed knowledge base. Thus, this research proposes a broad animal monitoring and tracking system, which will reveal a complete picture of animal life underground, for the first time.

To achieve the goals of the research a close collaboration with the Wildlife Conservation Research Unit at the University of Oxford will be formed. They will guide the design of the tracking collars and attach them to suitable badgers during regular research undertaken in Wytham Woods, Oxfordshire. Their expertise is also vital in framing the research to address biologically relevant questions. Data from this system will also be used by researchers in the University of Cambridge Computing Laboratory, to investigate social contact networks. Ultimately this insight into the detail of badgers' lives will help to unravel the true extent with which they interact with each other, and shed light not just on the behavioural-ecology of this species, but investigate their social systems and address important questions concerning the transmission of disease.