external image Jaguar-1.jpg

Kingdom: Animalia

Phylum: Chordata

Class: Mammalia

Order: Carnivora

Family: Felidae

Genus: Panthera

Species: P. onca

Range and Abundance:

The jaguar is the only of its species found in the Americas. It was once found in a larger area than it currently occupies, however, human activities and hunting have reduced its range. (see map).

Although they have historically been in U.S. territory, today there are virtually none found north of the Mexcan border.

A "black panther" or melanistic jaguar
A "black panther" or melanistic jaguar
Coloration and Morphology:

Jaguars are very large cats between 56 - 159 kg (124 - 350 lbs) and 1.62 - 1.82 meters (5.3 - 6 feet). Although not as big as their lion or tiger cousins, leopards are extremely muscular and built with great efficiency. They are excellent swimmers, climbers, and pouncers - the perfect build for a jungle habitat. Their jaws pack one of the most powerful bites on the planet, being able to pulverize bone and reptile shell.

The color of jaguars can vary depending on whether or not they are melanistic. Most jaguars have a light-brown to yellow undercoat with brown and black spots. These serve as camoflauge while the cat hunts. Melanistic jaguars (also called Black Panthers) can be entirely or mostly black, sometimes with hints of blue and purple. This is the result of an allele that, although dominant, remains rare in the species.

Interestingly, as one samples the sizes of jaguar jaws from North to South America, one finds that they increase. The reason for this is unknown. 3

As proved by this photograph of a jaguar pawprint, the great felines still prowl the Rain Forest near La Selva

Jaguars are a jungle cat and are built for it, but the big cats can also be found in tropical wetlands, where they tend to grow slightly larger and have lighter markings. Being great swimmers, they often stalk reptiles and fish in vernal pools during rainy seasons. Even in the rain forest, jaguars have a close association with the water. They are also found in trees. Male jaguars have a territory that is twice the size of a female's.


Ecologically, jaguars fill a crucial role as head of the rain forest food chain. In some places, the jaguar's habitat overlaps that of a cougar. However, because cougars tend to take smaller prey, the two are not normally in competition. The importance of apex predators cannot be underestimated, as it keeps down the populations of smaller mammals and reptiles, helping to keep the entire jungle ecosystem in equilibrium. Study and preservation of the jaguar is important for this reason, as apex predators have been eliminated from many temperate ecosystems, and the natural equilibrium has shifted detrimentally.
In places where the jaguar has been driven out, species such as the pecari become overabundant


As adults, jaguars are solitary figures that inhabit specific territories. Young males live a relatively nomadic life before winning their own territory, which is usually twice the size of the female's. Jaguars come together to copulate, and then separate. The female jaguar is responsible for rearing young, and will discourage adult male presence near her kittens to prevent infanticide. Jaguars are known to hunt primarily at night and are built for sneaking and pouncing rather than running after prey. With their powerful jaws, jaguars will deliver a deadly bite to the skull of an animal in order to kill it.


Jaguars prefer large prey such as deer, but will also consume smaller animals like dogs, monkeys, and reptiles.2 With such a powerful bite, jaguars are able to break through turtle shells to get at the meat within. When near human territories, jaguars may prey on livestock and horses. These giant cats are strictly carnivorous.1

Interaction with other species:

Being apex predators, jaguars are not symbiotic with any other animals. Their interaction with humans is not usually violent unless they feel threatened or are backed into a corner. Jaguars in captivity may attack their keepers. Due to deforestation and poaching, jaguar populations are declining, but efforts to save their population are underway throughout the Americas.

An ancient jaguar statue from the first century AD
An ancient jaguar statue from the first century AD
Cultural Significance:

Many ancient American cultures valued the jaguar as a powerful and sacred animal. The power of the jaguar is still respected in modern culture, and many sports teams, and even a brand of automobile, bear the name jaguar.

Personal Experience:

Although I did not see the jaguar while in Costa Rica, I did see its footprint on the way back from a hike. These prints were not there the twenty minutes before when we passed by the same patch of mud, which lead us to believe that the jaguar was tracking us. I also saw many hints of the jaguar in the culture of the Costa Rican people and some of their art. Finally, the lack of jaguars in La Selva led there to be an overabundance of peccaries.


1. Rodrigo Nuanaez, Brian Miller, and Fred Lindzey (2000). "Food habits of jaguars and pumas in Jalisco, Mexico". Journal of Zoology 252 (3): 373.

2. "Schaller, G. B. and Vasconselos, J. M. C. (1978). Jaguar predation on

capybara. Z. Saugetierk. 43: 296-301".

3. Dinets, Vladmir. "First documentation of melanism in the jaguar (Panthera onca) from northern Mexico".