Allan and Jon, fourth-grade students at St. George School, asked us how we identify an animal by its tracks. This is an excellent question! A big part of our daily work here at Chamela involves setting up 'scent stations' to record animal tracks so that we can tell which animals are present in the area.

A scent station consists of a smelly pellet placed in the middle of an area where the soil has been smoothed over. When an animal comes to smell the pellet, it leaves its tracks on the smooth soil. We set scent stations at 300-meter intervals along roads, trails, and streams that animals are likely to visit. The scent stations are checked daily. The number of tracks are recorded and each track is measured. The tracks are photographed and plaster casts made for later identification.

To identify a track, we use a guide with drawings of tracks, like the ones in this picture. Our guide includes many animals common to this area and information on the size (length and width) of their tracks.

For example, the length a jaguar track (forefoot) is 100 millimeters (4 inches long) by 120 millimeters (4.8 inches). Try drawing these tracks to scale (1 mm = .04 inches).

• jaguar forefoot - 100 mm x 120 mm
• puma forefoot - 80 mm x 90 mm
• coyote forefoot - 65 mm x 55 mm
• coatimundi forefoot - 60 mm x 45 mm
• ocelot forefoot - 50 mm x 55 mm
• jaguarundi forefoot - 30 mm x 35 mm

The shape of a track is another important clue to identifying the animal species. Notice in the animal track drawings how the toes and the pads of different animals are shaped and spaced. How big are the toe impressions relative to the pads? Which species have claws showing? Do you see a similarity in pattern among the wild cats that is different from the pattern of the coyote or coati?

In general, the toe impressions of cats (jaguars, ocelots, house cats) are smaller and asymmetrical, with one toe slightly ahead of the others. The pad is the dominant feature of the track and is shaped like an 'm' with a blunt top edge. Claw marks are not apparent. The toe impressions of dogs (coyotes, foxes, domestic dogs) are roughly the same size and appear symmetrical. The pad looks somewhat pointed at the top edge. Nail marks show.

In trying to identify a track, keep in mind that different soil conditions may alter the appearance of a track.

So, if you guessed that the mystery track is an ocelot, you are right! You can tell by:

1. the size of the track (a little more than half the length of the 90 mm knife)
2. the asymmetrical shape of the toes (one toe slightly ahead of the others)
3. the blunt m-shaped pad