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Expedition scientist Carlos López González prepares a live trap
Why We Are Here
by Dr. Carlos López González

Hi kids!

I am a wildlife biologist and have been researching wild cats and other carnivores at Chamela since 1992.

As predators, the carnivores play an important role in the forest ecosystem. Their feeding patterns directly impact the number of prey — small mammals, reptiles, birds, and insects in the entire forest.

This dry forest is thought to have a large number of carnivore species — six kinds of cats, two members of the canine family (coyote, gray fox), and a variety of smaller animals including three types of skunk.

However, we know very little about these animals — how many different species there are, which areas of the forest they visit, and how they relate to one another. For example, are carnivores such as pumas, ocelots, and coyotes competing for prey? How large an area do jaguarundi or foxes need to survive? What elements of the habitat are most important for conservation? The goal of our research is to find answers to these questions.

We are using different methods to document and track carnivore activity. One method is to place over 60 'live' traps along trails and riverbeds to capture the animals. These traps are like the ones shown in the photograph. The larger wire-cage trap is used to catch medium to small carnivores like ocelots and coatimundi (a relative of the raccoon). The smaller traps are used to catch the pygmy spotted skunk, a species of skunk found only in the Mexican dry forest.

Soft-catch leg-hold traps are used for the larger carnivores such as coyotes and jaguars. We have captured only one jaguar in five years! Several coyotes have been caught.

'Live' traps are designed to keep the animals alive and minimize any harm to them. The traps are baited with chicken, sausage, and other tasty items to lure the animals into the traps.

If a 'study' animal is caught, we take measurements and examine the animal carefully to assess its health. The animal is then tattooed and released. Some animals like ocelots, coyotes, and skunks are fitted with radio-transmitter collars so that we can track their movements after the animals are released. Coatimundis are the most frequently captured species — 47 'coatis' since 1992, followed by pygmy spotted skunks (36 total), and ocelots (28 total).

We use two other kinds of traps: a 'camera' trap and a 'scent station' trap. These are not really traps because they do not capture the animals. The camera trap takes a photograph of the animal as it goes by. The scent station is a small area of the trail that we prepare with a smelly pellet to attract animals. We then check the tracks.

In the next field report, I'll show you how we interpret photographs and tracks, and you can try out your skill identifying some 'mystery' animals.

Photo courtesy of Dr. Carlos López González/Earthwatch Institute