The jaguar (Panthera onca) is a member of the cat family (Felidae), and is the largest representative of this family in the western hemisphere. They are native to Mexico, Amazonia, Venezuela and the Guianas (historically, their range was far greater; see Conservation status).

General biology and behaviour

Jaguars are roaring cats, like the lion, tiger and leopard, and are truly spectacular animals. Adult males average 200 pounds (85 kg) or more, while females average around 150 pounds (70 kg). The size of individuals varies with their geographic location (northern specimens are smaller than those in the south) and their habitat. Those living in heavily forested areas are smaller than those living in or near the open.

When compared to the other members of the genus, jaguars have shorter legs and a more stocky build. They have a spotted coat, but an appearance significantly different than the other spotted cats, the leopard and the cheetah. Their coat is covered in broken-edged rosettes that contain the black spots, giving the appearance of a mosaic. The cheetah and leopard, on the other hand, simply have their spots distributed more or less evenly along a solid background. The southern jaguars also have a relatively high natural rate of melanism, meaning there are pure black specimens regularly observed in the wild.

The jaguar is always associated with water. They swim well, and tend to inhabit the rain forest and flood plains or swamps. They have also been found in scrub lands and dry deciduous forests, but this is not considered optimal habitat. They tend to remain at relatively low elevations, remaining below 2700 meters above sea level (however, individuals have been found as high as 3800 meters in Costa Rica).

Jaguars are solitary, territorial animals. They come together as adults to breed, but otherwise live without contact with other jaguars. They mark their territories with urine and by scratching trees. Each jaguar will patrol a range of roughly 15 square kilometres, but in areas of high population density, certain portions of the range will be shared with other jaguars.

Female jaguars are capable of breeding year round, but research on a number of wild populations in South America has found that they time reproduction with the rainy season, so the female will have her cubs when food is most abundant. After copulation, a female will gestate for roughly 100 days, and then give birth to 1 to 4 cubs (the average is 2). These young will remain with their mother for 18-24 months, after which time they will leave to find their own territories. At this age, most females cubs are sexually mature, while males must attain an age of 3 to 4 years first.

Jaguars prey on a very diverse range of species. Adults will eat large prey, such as the peccary, deer, tapir and capybara. Given the size of the prey and the fact that they are solitary hunters, jaguars will often leave large animals in a cache for later consumption. They will also target cattle being farmed by the local populations, putting them into conflict with humans (see Conservation status). Their predatory strategy is fairly simple. They remain hidden, either in a tree or in the scrub brush, and ambush their prey. They are the only cat species which pierces the skull of its prey with its teeth in order to kill. Some scientists have hypothesized that this ability may have evolved as a result of the super-abundant reptilian prey available to jaguars during the late Pleistocene. As a final note, while rare, jaguars do in fact hunt and kill humans.

Finally, the jaguar is a top predator in all the ecosystems it inhabits. Not only do they play a crucial ecological role as the top predator (culling the weak and the sick), but some scientists maintain that they are in fact keystone predators, meaning their ecological importance outweighs their numbers or biomass. Many of the tropical food webs containing the jaguar go hopelessly out of balance when the cat is removed, having negative impacts on many other native species.

Taxonomy

Family: Felidae Subfamily: Pantherinae Genus: Panthera Species: onca There are several subspecies of jaguar, some no longer extant. These subspecies are: P. o. onca, P. o. arizonensis, P. o. centralis, P. o. goldmani, P. o. hernandesii, P. o. palustris, P. o. peruvianus, and P. o. veracucis. Some scientists, however, believe that there may be only two subspecies, and as is the case with subspecies classifications, modifications occur regularly. The above list represents the closest thing to a consensus, at present.

Their closest relatives are the other members of the genus Panthera: the lion, the leopard and the tiger.

Conservation status

The jaguar's range was, historically, from Texas and Arizona to Argentina. Their range has been reduced by over 50 percent in the past 500 years due to hunting and habitat destruction. However, the species was devastated in the 20th century as a result of a very active trade in jaguar pelts1. However, anti-fur campaigns in the 1970s dramatically reduced the value of these pelts, and thus the hunting of the species. At present, there are an estimated 15 000 jaguars living in the wild. However, high deforestation rates in the species' native range continues to place heavy pressure on the jaguar, and they are often shot on sight by cattle ranchers who fear for their livestock. Particularly concerning is that translocation of problem individuals does not seem to alleviate the problem; jaguars return to hunt the cattle in their original range. As such, many cattle ranchers in Venezuela and Brazil go so far as to hire hunting parties to pursue all jaguars local to the grazing lands of their cattle, whether the cattle are preyed upon or not. Finally, the jaguar is also pressured, although only slightly so, by competition for resources with indigenous populations.

The numbers of this species have become so reduced that they are classified as endangered (Appendix 1) by the Convention on International Trade in Endangered Species (CITES), by the Mexico and US Fish and Wildlife Service, and as vulnerable by the International Union for Conservation of Nature.

Importance to humans

The jaguar is also known as El tigre, Frijolillo and Tigre leon across South America. They are venerated by indigenous peoples as gods, and some tribes believe that they not only devour the bodies of the living, but also the souls of the dead. The ruins in the Yucatan peninsula contain great deals of iconography, and the jaguar plays a particularly prominent role. The Mayans believed that the jaguar was a supernatural being who rose each day and prowled, like the sun, from east to west. Then, during the evening the jaguar sun fought with the lords of the underworld all night. Each evening, the jaguar won using its strength and cunning, thus ensuring that the sun rose each day. There are countless other stories and fables involving the jaguar, often with contrary messages.

1 I know I shouldn't, but I really can't help myself: Fuckers!


Information culled from
* http://lynx.uio.no/catfolk/onca-02.htm
* http://www.felidtag.org/pages/Educational/FactSheets/jaguar.htm
* http://greennature.com/article138.html
* http://www.gf.state.az.us/frames/fishwild/jaguar.htm
* http://www.oneworldjourneys.com/jaguar/jaguar.html