Data from: An active-radio-frequency-identification system capable of identifying co-locations and social-structure: validation with a wild free-ranging animal

Behavioural events that are important for understanding sociobiology and
movement ecology are often rare, transient and localised, but can occur at
spatially distant sites e.g. territorial incursions and co-locating
individuals. Existing animal tracking technologies, capable of detecting
such events, are limited by one or more of: battery life; data resolution;
location accuracy; data security; ability to co-locate individuals both
spatially and temporally. Technology that at least partly resolves these
limitations would be advantageous. European badgers (Meles meles L.),
present a challenging test-bed, with extra-group paternity (apparent from
genotyping) contradicting established views on rigid group territoriality
with little social-group mixing. In a proof of concept study we assess the
utility of a fully automated active-radio-frequency-identification (aRFID)
system combining badger-borne aRFID-tags with static,
wirelessly-networked, aRFID-detector base-stations to record badger
co-locations at setts (burrows) and near notional border latrines. We
summarise the time badgers spent co-locating within and between
social-groups, applying network analysis to provide evidence of
co-location based community structure, at both these scales. The aRFID
system co-located animals within 31.5 m (adjustable) of base-stations.
Efficient radio transmission between aRFIDs and base-stations enables a 20
g tag to last for 2–5 years (depending on transmission interval). Data
security was high (data stored off tag), with remote access capability.
Badgers spent most co-location time with members of their own
social-groups at setts; remaining co-location time was divided evenly
between intra- and inter-social-group co-locations near latrines and
inter-social-group co-locations at setts. Network analysis showed that
20–100% of tracked badgers engaged in inter-social-group mixing per week,
with evidence of trans-border super-groups, that is, badgers frequently
transgressed notional territorial borders. aRFID occupies a distinct niche
amongst established tracking technologies. We validated the utility of
aRFID to identify co-locations, social-structure and inter-group mixing
within a wild badger population, leading us to refute the conventional
view that badgers (social-groups) are territorial and to question
management strategies, for controlling bovine TB, based on this model.
Ultimately aRFID proved a versatile system capable of identifying
social-structure at the landscape scale, operating for years and suitable
for use with a range of species.