Tracking the lighters and collecting position data is achieved with
the help of research transmitters normally used as animal implants
in wildlife habitat studies.

Each innocuous looking lighter case houses the transmitter and its
little antenna out of sight. Once assembled, the lighter emits a signal
on a specific frequency – visible to our scanners when in range.

Seeing a lighter is near, switching on close-range directional antennas
tells us more.

The telemetry data collected is analysed using software for wildlife
study, extracting information about the lighters and the urban habitats
described by their movements. The software, feeding on the times and
positions of lighter fixes, performs a polygon or grid cell analysis
for a visual map of the home-ranges.

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For a short overview of how biotelemetry works in general, in
'Traces of Fire' as well as a couple of links to resources on the
topic click here.

Details on the lighters' components are to be found here.

Details on the lighters' assembly are to be found here.