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Carlos tracking a radio-collared coyote.
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.

Photo courtesy of Jen Vogel/Earthwatch Institute