Types of Collars Used
Two types of collars, VHF and GPS, are used. VHF are the traditional
radio collar, which sends out a steady signal which one can locate with
an antenna and receiver, either on foot, from a vehicle or from the
air (the latter being most efficient, but most expensive). A VHF collar
lasts at least three years on a lion, after which a new one with fresh
batteries must be fitted
GPS collars are far more sophisticated – they incorporate a GPS
receiver which can be set to take position fixes at any time of day
or night, which are then stored in the collar until remotely downloaded
to a computer via a UHF radio link; one does not need to recapture the
lion in order to get the data. Thus, we can map a lion’s movements
day and night, allowing unprecedented studies of home range, movements
according to habitat types, human activity or wildlife concentrations,
etc. GPS collars cost ten times as much as VHF ones, and consume more
battery power: a GPS collar taking frequent fixes lasts perhaps one
year, after which it must be changed.
A satellite GPS collar is currently experimented. Its higher cost ($7,000)
is justify by immediately available information and no need of a receiver.
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