Geography Reference
In-Depth Information
faster-than-average movements (shown in dark blue) occurred during December
and January, most probably the result of bouts of commuting from the den to
seasonally available food resources that were dispersed over long distances.
Especially during the austral summer months, movement speeds near the end of
nightly active periods were lower than average, suggesting a tendency of the
animal to rest or groom outside of the den before retiring to sleep. Also during
summer months there were occasions when fixes were recorded before sunset.
Most likely these occurred during nights when the possum slept in epiphytes,
where it was possible for the GPS collar to determine locations, which usually is
not possible when GPS collars are in tree cavities or holes in the ground where
satellite signals are occluded by surrounding dense woody or stone materials
(Dennis et al.
2010
; Dennis and Shah
2012
). With the matrix view, it was easy to
see horizontal changes. An interesting general shift of the start and finish of active
time emerged. There was an upward shift towards later finishing times in the
autumn months of March to May, which might reflect the possum's response to
increasingly long nights.
4 Discussion and Conclusion
This chapter has introduced an experimental, movement-specific, visualisation
toolset that is being tested with both human and animal activity movement data
sets. We introduced the tool set with an example of the daily lifestyle of human
residents of Halifax, but have concentrated more on presenting outputs from a data
set of GPS-tracked possums. The goal of this has been to compare the capabilities
of certain visualisation tools in the context of different species in different geog-
raphies. The Ringmap project has used a time geography approach to explore more
powerful tools for visualising movement of animals by focusing on an integration
of space, time, activity and environmental factors and coincides with the rapid
evolution of sophisticated tracking technologies that foster the conditions for
advancing conceptualisation of a 'movement ecology' paradigm aimed at animal
studies. The overlaps between these approaches has been noted, as has the parallel
gap between the animal and human research communities, and the nature of this
common ground has been explored a little within the text. Three specific repre-
sentations have been compared for this paper.
Not surprisingly, traditional timelines have proven equally capable of adding
value to basic two-dimensional maps. However, extra value has been revealed by
linking environment factors (vegetation type) and/or derived 'activity' parameters
to the timeline display.
The ringmap representation has proved to be flexible in providing a compact
means of exploring activity patterns over markedly different spatio-temporal res-
olutions and observational periods be they generated by humans or possums.
For possums it has been successfully improved by integrating the seasonal
cyclicity in such a way that it incorporates the fluctuating duration of the possum's
low light 'day'. The inner space of a ringmap can also be used flexibly, displaying
