Radio-tracking
Cats & Other Carnivores
by Dr. Carlos López González
Aileen from the Murray Language Academy asks: 'Is
it hard finding the wild cats even with the traps and
advances in technology?' The answer is definitely 'yes.'
These cats are very shy and elusive animals.
The box traps, camera photos, and tracks left in scent
stations help us to make estimates about numbers of
animals, their diversity, and their physical condition.
However, we really do not know much about what they
do or where they go the rest of the day or night. There
is a whole lot more to be learned.
Collaring animals with radio transmitters and then
tracking them 24 hours a day has been a tremendous help
to us in finding out more about their daily activity
patterns. So far, we have been able to radio-collar
and track ocelots, jaguarundis, coyotes, gray foxes,
coatimundis, pygmy spotted skunks, and hog-nosed skunks
using transmitters.
In the photo, you see a collared coyote. The collar
contains a small radio transmitter that beeps signals
that can be picked up by a radio receiver and antenna.
Depending on how loud the beeps are, we can figure out
the animal's direction and take a compass bearing. With
a compass reading from another hilltop taken at the
same time, we can determine through a process called
'triangulation' the exact location of the animal.
Through recording compass locations and triangulation
data over a 24-hour period, we have found out a lot
about the home ranges of different animals and the distance
they travel each day. For example, you can compare the
daily distances we've calculated for each of the animals
below:
coyote: 12 to 20 km
ocelot: 6.45 km
coatimundi: 3.5 km
pygmy spotted skunk: 1.48 km
Through radio tracking we have also discovered three
resting areas for ocelots two located along drainages,
and one under a human-built culvert.
We have also been able to find out more about the
areas of the forest that different animals use more
frequently and the extent that their territories overlap.
For example, ocelots appear to be using more of the
dense cover of the forest. Coyotes are using less of
the forest than expected, and more of the grasslands.
All of this information will help us better manage
the forest resources for conservation of wild cats and
other animals.