Overall, the jaguar is the largest native cat species of the New World and the third largest in the world. This spotted cat closely resembles the leopard, but is usually larger and sturdier. It ranges across a variety of forested and open terrains, but its preferred habitat is tropical and subtropical moist broadleaf forest, swamps and wooded regions. The jaguar enjoys swimming and is largely a solitary, opportunistic, stalk-and-ambush predator at the top of the food chain. As a keystone species it plays an important role in stabilizing ecosystems and regulating prey populations.
While international trade in jaguars or their body parts is prohibited, the cat is still frequently killed, particularly in conflicts with ranchers and farmers in South America. Although reduced, its range remains large. Given its historical distribution, the jaguar has featured prominently in the mythology of numerous indigenous American cultures, including those of the Maya and Aztec.
Etymology
The word 'jaguar' is thought to derive from the Tupian word yaguara, meaning "beast of prey".[2] The word entered English presumably via the Amazonian trade language Tupinambá, via Portuguese jaguar.[3][4] The specific word for jaguar is yaguareté, with the suffix -eté meaning "real" or "true".[5]The word 'panther' derives from classical Latin panthēra, itself from the ancient Greek pánthēr (πάνθηρ).[6]
In Mexican Spanish, its nickname is el tigre: 16th century Spaniards had no native word in their language for the jaguar, which is smaller than a lion, but bigger than a leopard, nor had ever encountered it in the Old World, and so named it after the tiger, since its ferocity would have been known to them through Roman writings and popular literature during the Renaissance.[7]
Onca is the Portuguese onça, with the cedilla dropped for typographical reasons, found in English as ounce for the snow leopard, Panthera uncia. It derives from the Latin lyncea lynx, with the letter L confused with the definite article (Italian lonza, Old French l'once).[8]
Evolution
Fossil skull of a Pleistocene North American jaguar (Panthera onca augusta)
Phylogenetic studies generally have shown the clouded leopard (Neofelis nebulosa) is basal to this group.[12][13][14]
Fossils of extinct Panthera species, such as the European jaguar (P. gombaszoegensis) and the American lion (P. atrox), show characteristics of both the jaguar and the lion (P. leo).[12] Based on morphological evidence, the British zoologist Reginald Innes Pocock concluded that the jaguar is most closely related to the leopard (P. pardus).[15] However, DNA-based evidence is inconclusive, and the position of the jaguar relative to the other species varies between studies.[12][13][14][9]
Taxonomy
In 1758, Carl Linnaeus described the jaguar in his work Systema Naturae and gave it the scientific name Felis onca.[16] In the 19th and 20th centuries, several jaguar type specimens formed the basis for descriptions of subspecies.[17] In 1939, Reginald Innes Pocock recognized eight subspecies based on geographic origins and skull morphology of these specimens.[15] Pocock did not have access to sufficient zoological specimens to critically evaluate their subspecific status, but expressed doubt about the status of several. Later consideration of his work suggested only three subspecies should be recognized. The description of P. o. palustris was based on a fossil skull.[18] The author of Mammal Species of the World listed nine subspecies and both P. o. palustris or P. o. paraguensis separately.[17]Results of morphologic and genetic research indicate a clinal north–south variation between populations, but no evidence for subspecific differentiation.[10][19] A subsequent, more detailed study confirmed the predicted population structure within jaguar populations in Colombia.[11]
IUCN Red List assessors for the species and members of the Cat Specialist Group do not recognize any jaguar subspecies as valid.[1][20] The following table is based on the former classification of the species provided in Mammal Species of the World.[17]
| Formerly recognised subspecies | Region | Image |
|---|---|---|
|
South America: Venezuela to the Amazon rainforest, coastal Peru, the Pantanal regions of Mato Grosso and Mato Grosso do Sul, Brazil, along the Paraguay River into Paraguay and northeastern Argentina | _female_Piquiri_River.JPG) |
Female South American jaguar at Piquiri River, Mato Grosso state, Brazil
| ||
| Central and North America: Colombia, Guatemala, Belize, El Salvador to Yucatán Peninsula, Mexico and southern Arizona, United States. |  |
El Jefe in Arizona, United States
|
Characteristics
The head of the jaguar is robust and the jaws extremely powerful
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Comparative illustration of jaguar (bottom) with leopard and cheetah
Its size and weight vary considerably: weights are normally in the range of 56–96 kg (123–212 lb). Exceptionally big males have been recorded to weigh as much as 158 kg (348 lb).[25][26] The smallest females weigh about 36 kg (79 lb).[25] Females are typically 10–20 percent smaller than males. The length, from the nose to the base of the tail, varies from 1.12 to 1.85 m (3.7 to 6.1 ft). The tail is the shortest of any big cat, at 45 to 75 cm (18 to 30 in) in length.[25][27] Legs are also short, but thick and powerful, considerably shorter when compared to a small tiger or lion in a similar weight range. The jaguar stands 63 to 76 cm (25 to 30 in) tall at the shoulders.[23]
Further variations in size have been observed across regions and habitats, with size tending to increase from north to south. Mexican jaguars in the Chamela-Cuixmala Biosphere Reserve on the Pacific coast weighed just about 50 kg (110 lb), about the size of a female cougar.[28] South American jaguars in Venezuela or Brazil are much larger with average weights of about 95 kg (209 lb) in males and of about 56–78 kg (123–172 lb) in females.[18]
A short and stocky limb structure makes the jaguar adept at climbing, crawling, and swimming.[23] The head is robust and the jaw extremely powerful, it has the third highest bite force of all felids, after the tiger and lion.[29] A 100 kg (220 lb) jaguar can bite with a force of 503.6 kgf (1,110 lbf) at canine teeth and 705.8 kgf (1,556 lbf) at carnassial notch.[30] This allows it to pierce the shells of armored reptiles and turtles.[31] A comparative study of bite force adjusted for body size ranked it as the top felid, alongside the clouded leopard and ahead of the tiger and lion.[32] It has been reported that "an individual jaguar can drag an 800 lb (360 kg) bull 25 ft (7.6 m) in its jaws and pulverize the heaviest bones".[33]
While the jaguar closely resembles the leopard, it is generally sturdier and heavier, and the two animals can be distinguished by their rosettes: the rosettes on a jaguar's coat are larger, fewer in number, usually darker, and have thicker lines and small spots in the middle that the leopard lacks. Jaguars also have rounder heads and shorter, stockier limbs compared to leopards.[34]
Colour variation
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A melanistic jaguar is a color morph which occurs at about 6 percent frequency in populations
Some evidence indicates that the melanistic allele is dominant, and being supported by natural selection.[37] The black form may be an example of heterozygote advantage; breeding in captivity is not yet conclusive on this. Melanistic jaguars (or "black" jaguars) occur primarily in parts of South America, and are virtually unknown in wild populations residing in the subtropical and temperate regions of North America; they have never been documented north of Mexico's Isthmus of Tehuantepec.[38]
Extremely rare albino individuals, sometimes called white panthers, also occur among jaguars, as with the other big cats.[24] As usual with albinos in the wild, selection keeps the frequency close to the rate of mutation.
Distribution and habitat
The jaguar inhabits a variety of forested and open habitat, but is strongly associated with the presence of water.
It occurs in the 400 km² Cockscomb Basin Wildlife Sanctuary in Belize, the 5,300 km² Sian Ka'an Biosphere Reserve in Mexico, the approximately 15,000 km2 Manú National Park in Peru, the approximately 26,000 km2 Xingu National Park in Brazil, and numerous other reserves throughout its range.
The inclusion of the United States in the list is based on occasional sightings in the southwest, particularly in Arizona,[39] New Mexico and Texas. There are rock drawings made by the Hopi, Anasazi, and Pueblo all over the desert and chaparral regions.[40] There are records of the beast being sold for its pelt in the vicinity of San Antonio, Texas for $18 apiece in the mid 19th century[41] and there are records from well before California was a state that fit the description of this cat.[42]
In the early 20th century, the jaguar's range extended as far north as the Grand Canyon and possibly Colorado, and as far west as Monterey in Northern California.[43][44][45] The jaguar is a protected species in the United States under the Endangered Species Act, which has stopped the shooting of the animal for its pelt. Jaguar skins are also treated as illegal contraband by the US government and otherwise by and large Americans have stopped wearing fur coats made of the pelts of spotted cats as citizens are aware of the international plight of big cats. Unfortunately the cessation of hunting came too late to save the jaguar population from crashing and no kittens have been known to have been born on the other side of the Mexican-American border in generations.
In 1996 and from 2004 on, hunting guides and wildlife officials in Arizona photographed and documented jaguars in the southern part of the state.[46] Between 2004 and 2007, two or three jaguars have been reported by researchers around Buenos Aires National Wildlife Refuge in southern Arizona. One of them, called 'Macho B', had been previously photographed in 1996 in the area.[47] For any permanent population in the US to thrive, protection from killing, an adequate prey base, and connectivity with Mexican populations are essential.[48] In February 2009, a 53.5 kg (118 lb) jaguar was caught, radio-collared and released in an area southwest of Tucson, Arizona; this is farther north than had previously been expected and represents a sign there may be a permanent breeding population of jaguars within southern Arizona. The animal was later confirmed to be indeed the same male individual ('Macho B') that was photographed in 2004.[49] On 2 March 2009, Macho B was recaptured and euthanized after he was found to be suffering from kidney failure; the animal was thought to be 16 years old, older than any known wild jaguar.[50]
Completion of the United States–Mexico barrier as currently proposed will reduce the viability of any population currently residing in the United States, by reducing gene flow with Mexican populations, and prevent any further northward expansion for the species.[51]
The historic range of the species included much of the southern half of the United States, and in the south extended much farther to cover most of the South American continent. In total, its northern range has receded 1,000 km (620 mi) southward and its southern range 2,000 km (1,200 mi) northward. Ice age fossils of the jaguar, dated between 40,000 and 11,500 years ago, have been discovered in the United States, including some at an important site as far north as Missouri. Fossil evidence shows jaguars of up to 190 kg (420 lb), much larger than the contemporary average for the animal.[52]
The habitat of the cat typically includes the rain forests of South and Central America, open, seasonally flooded wetlands, and dry grassland terrain. Of these habitats, the jaguar much prefers dense forest;[24] the cat has lost range most rapidly in regions of drier habitat, such as the Argentine pampas, the arid grasslands of Mexico, and the southwestern United States.[1] The cat will range across tropical, subtropical, and dry deciduous forests (including, historically, oak forests in the United States). The jaguar prefers to live by rivers, swamps, and in dense rainforest with thick cover for stalking prey. Jaguars have been found at elevations as high as 3,800 m, but they typically avoid montane forest and are not found in the high plateau of central Mexico or in the Andes.[24] The jaguars preferred habitats are usually swamps and wooded regions, but jaguars also live in scrublands and deserts.[53]
Ecology and behavior
Ecological role
The adult jaguar is an apex predator, meaning it exists at the top of its food chain and is not preyed on in the wild. The jaguar has also been termed a keystone species, as it is assumed, through controlling the population levels of prey such as herbivorous and granivorous mammals, apex felids maintain the structural integrity of forest systems.[28][54] However, accurately determining what effect species like the jaguar have on ecosystems is difficult, because data must be compared from regions where the species is absent as well as its current habitats, while controlling for the effects of human activity. It is accepted that mid-sized prey species undergo population increases in the absence of the keystone predators, and this has been hypothesized to have cascading negative effects.[55] However, field work has shown this may be natural variability and the population increases may not be sustained. Thus, the keystone predator hypothesis is not accepted by all scientists.[56]The jaguar also has an effect on other predators. The jaguar and the cougar, which is the next-largest feline of South America, but the biggest in Central or North America,[28] are often sympatric (related species sharing overlapping territory) and have often been studied in conjunction. The jaguar tends to take larger prey, usually over 22 kg (49 lb) and the cougar smaller, usually between 2 and 22 kg (4.4 and 48.5 lb), reducing the latter's size.[57][58] This situation may be advantageous to the cougar. Its broader prey niche, including its ability to take smaller prey, may give it an advantage over the jaguar in human-altered landscapes;[28] while both are classified as near-threatened species, the cougar has a significantly larger current distribution. Depending on the availability of prey, the cougar and jaguar may even share it.[59]
Reproduction and life cycle
4-month-old cub at the Salzburg Zoo
Generation length of the jaguar is 9.8 years.[62]
Female estrus is 6–17 days out of a full 37-day cycle, and females will advertise fertility with urinary scent marks and increased vocalization.[60] Both sexes will range more widely than usual during courtship.[citation needed] Pairs separate after mating, and females provide all parenting. The gestation period lasts 93–105 days; females give birth to up to four cubs, and most commonly to two. The mother will not tolerate the presence of males after the birth of cubs, given a risk of infanticide; this behavior is also found in the tiger.[63]
The young are born blind, gaining sight after two weeks. Cubs are weaned at three months, but remain in the birth den for six months before leaving to accompany their mother on hunts.[64] They will continue in their mother's company for one to two years before leaving to establish a territory for themselves. Young males are at first nomadic, jostling with their older counterparts until they succeed in claiming a territory. Typical lifespan in the wild is estimated at around 12–15 years; in captivity, the jaguar lives up to 23 years, placing it among the longest-lived cats.[65]
Social activity
Jaguars at Cameron Park Zoo in Waco, Texas
Like the other big cats, the jaguar is capable of roaring[69][70] and does so to warn territorial and mating competitors away; intensive bouts of counter-calling between individuals have been observed in the wild.[31] Their roar often resembles a repetitive cough, and they may also vocalize mews and grunts.[65] Mating fights between males occur, but are rare, and aggression avoidance behavior has been observed in the wild.[67] When it occurs, conflict is typically over territory: a male's range may encompass that of two or three females, and he will not tolerate intrusions by other adult males.[63]
The jaguar is often described as nocturnal, but is more specifically crepuscular (peak activity around dawn and dusk). Both sexes hunt, but males travel farther each day than females, befitting their larger territories. The jaguar may hunt during the day if game is available and is a relatively energetic feline, spending as much as 50–60 percent of its time active.[24] The jaguar's elusive nature and the inaccessibility of much of its preferred habitat make it a difficult animal to sight, let alone study.
Hunting and diet
The jaguar has an exceptionally powerful bite that allows it to pierce the shells of armored prey
There is evidence that jaguars in the wild consume the roots of Banisteriopsis caapi.[76]
While the jaguar often employs the deep throat-bite and suffocation technique typical among Panthera, it sometimes uses a killing method unique amongst cats: it pierces directly through the temporal bones of the skull between the ears of prey (especially the capybara) with its canine teeth, piercing the brain.[77] This may be an adaptation to "cracking open" turtle shells; following the late Pleistocene extinctions, armored reptiles such as turtles would have formed an abundant prey base for the jaguar.[31][24] The skull bite is employed with mammals in particular; with reptiles such as the caiman, the jaguar may leap onto the back of the prey and sever the cervical vertebrae, immobilizing the target. When attacking sea turtles, including the huge leatherback sea turtle which weighs about 385 kg (849 lb) on average, as they try to nest on beaches, the jaguar will bite at the head, often beheading the prey, before dragging it off to eat.[78] Reportedly, while hunting horses, a jaguar may leap onto their back, place one paw on the muzzle and another on the nape and then twist, dislocating the neck. Local people have anecdotally reported that when hunting a pair of horses bound together, the jaguar will kill one horse and then drag it while the other horse, still living, is dragged in their wake.[79] With prey such as smaller dogs, a paw swipe to the skull may be sufficient to kill it.
Illustration of a jaguar killing a tapir, the largest native land animal in its range
On killing prey, the jaguar will drag the carcass to a thicket or other secluded spot. It begins eating at the neck and chest, rather than the midsection. The heart and lungs are consumed, followed by the shoulders.[63] The daily food requirement of a 34 kg (75 lb) animal, at the extreme low end of the species' weight range, has been estimated at 1.4 kg (3.1 lb).[43] For captive animals in the 50–60 kg (110–130 lb) range, more than 2 kg (4.4 lb) of meat daily are recommended.[80] In the wild, consumption is naturally more erratic; wild cats expend considerable energy in the capture and kill of prey, and they may consume up to 25 kg (55 lb) of meat at one feeding, followed by periods of famine.[81]
Man-eating
Unlike all other Panthera species, jaguars very rarely attack humans. However, jaguar attacks appear to be on the rise with increased human encroachment on their habitat and a decrease in prey populations.[82] Sometimes jaguars in captivity attack zookeepers.[83] In addition, it appears that attacks on humans had been more common in the past, at least after conquistadors arrived in the Americas, to the extent that the jaguar had a fearsome reputation in the Americas, akin to the lion and tiger in the Old World. Nevertheless, even in those times, the jaguar's chief prey was the capybara, not the human, and Charles Darwin reported a saying of Native Americans that people would not have to fear the jaguar much, as long as capybaras were abundant.[84]Threats
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A South American jaguar killed by Theodore Roosevelt
jaguar hunting scene with dogs – MHNT
The major risks to the jaguar include deforestation across its habitat, increasing competition for food with human beings, especially in dry and unproductive habitat,[1][87] poaching, hurricanes in northern parts of its range, and the behavior of ranchers who will often kill the cat where it preys on livestock. When adapted to the prey, the jaguar has been shown to take cattle as a large portion of its diet; while land clearance for grazing is a problem for the species, the jaguar population may have increased when cattle were first introduced to South America, as the animals took advantage of the new prey base. This willingness to take livestock has induced ranch owners to hire full-time jaguar hunters.[65]
The skins of wild cats and other mammals have been highly valued by the fur trade for many decades. From the beginning of the 20th-century Jaguars were hunted in large numbers, but over-harvest and habitat destruction reduced the availability and induced hunters and traders to gradually shift to smaller species by the 1960s. The international trade of jaguar skins had its largest boom between the end of the Second World War and the early 1970, due to the growing economy and lack of regulations. From 1967 onwards, the regulations introduced by national laws and international agreements diminished the reported international trade from as high as 13000 skins in 1967, through 7000 skins in 1969, until it became negligible after 1976, although illegal trade and smuggling continue to be a problem. During this period, the biggest exporters were Brazil and Paraguay, and the biggest importers were the US and Germany.[88]
Conservation
A melanistic jaguar
Adult jaguar in Cameron Park Zoo, Waco, Texas
Jaguar Conservation Units
Jaguar conservation is complicated because of the species' large range spanning 18 countries with different policies and regulations. Specific areas of high importance for jaguar conservation, so-called "Jaguar Conservation Units" (JCU) were determined in 2000. These are large areas inhabited by at least 50 jaguars. Each unit was assessed and evaluated on the basis of size, connectivity, habitat quality for both jaguar and prey, and jaguar population status. That way, 51 Jaguar Conservation Units were determined in 36 geographic regions as priority areas for jaguar conservation including:[86]- the Sierra Madre of Mexico
- the Selva Maya tropical forests extending over Mexico, Belize, and Guatemala
- the Chocó-Darién moist forests from Honduras, Panama to Colombia
- Sierra de Tamaulipas
- Venezuelan Llanos
- northern Cerrado and Amazon basin in Brazil
- Misiones Province in Argentina
In 1986, the Cockscomb Basin Wildlife Sanctuary was established in Belize as the world's first protected area for jaguar conservation.[91]
Given the inaccessibility of much of the species' range, particularly the central Amazon, estimating jaguar numbers is difficult. Researchers typically focus on particular bioregions, thus species-wide analysis is scant. In 1991, 600–1,000 (the highest total) were estimated to be living in Belize. A year earlier, 125–180 jaguars were estimated to be living in Mexico's 4,000-km2 (2400-mi2) Calakmul Biosphere Reserve, with another 350 in the state of Chiapas. The adjoining Maya Biosphere Reserve in Guatemala, with an area measuring 15,000 km2 (9,000 mi2), may have 465–550 animals.[92] Work employing GPS telemetry in 2003 and 2004 found densities of only six to seven jaguars per 100 km2 in the critical Pantanal region, compared with 10 to 11 using traditional methods; this suggests the widely used sampling methods may inflate the actual numbers of cats.[93]
Approaches
In setting up protected reserves, efforts generally also have to be focused on the surrounding areas, as jaguars are unlikely to confine themselves to the bounds of a reservation, especially if the population is increasing in size. Human attitudes in the areas surrounding reserves and laws and regulations to prevent poaching are essential to make conservation areas effective.[94]To estimate population sizes within specific areas and to keep track of individual jaguars, camera trapping and wildlife tracking telemetry are widely used, and feces may be sought out with the help of detector dogs to study jaguar health and diet.[95][96] Current conservation efforts often focus on educating ranch owners and promoting ecotourism.[97] The jaguar is generally defined as an umbrella species – its home range and habitat requirements are sufficiently broad that, if protected, numerous other species of smaller range will also be protected.[98] Umbrella species serve as "mobile links" at the landscape scale, in the jaguar's case through predation. Conservation organizations may thus focus on providing viable, connected habitat for the jaguar, with the knowledge other species will also benefit.[97]
Ecotourism setups are being used to generate public interest in charismatic animals such as the jaguar, while at the same time generating revenue that can be used in conservation efforts. Audits done in Africa have shown that ecotourism has helped in African cat conservation. As with large African cats, a key concern in jaguar ecotourism is the considerable habitat space the species requires, so if ecotourism is used to aid in jaguar conservation, some considerations need to be made as to how existing ecosystems will be kept intact, or how new ecosystems that are large enough to support a growing jaguar population will be put into place.[99]
The United States
The only extant cat native to North America that roars,[100] the jaguar was recorded as an animal of the Americas by Thomas Jefferson in 1799.[101] Jaguars are still occasionally sighted in Arizona and New Mexico, such as El Jefe,[102][103] prompting actions for its conservation by authorities.[100] For example, on August 20, 2012, the USFWS proposed setting aside 838,232 acres in Arizona and New Mexico — an area larger than Rhode Island — as critical jaguar habitat.[104]In mythology and culture
Pre-Columbian Americas
Jaguar warrior in the Aztec culture
Copy of the Book of Chilam Balam of Ixil in the National Museum of Anthropology (Mexico)
Statuette of Karajà in the Museum of Toulouse
In Mesoamerica, the Olmec—an early and influential culture of the Gulf Coast region roughly contemporaneous with the Chavín—developed a distinct "were-jaguar" motif of sculptures and figurines showing stylised jaguars or humans with jaguar characteristics. In the later Maya civilization, the jaguar was believed to facilitate communication between the living and the dead and to protect the royal household. The Maya saw these powerful felines as their companions in the spiritual world, and a number of Maya rulers bore names that incorporated the Mayan word for jaguar (b'alam in many of the Mayan languages). Balam (Jaguar) remains a common Maya surname, and it is also the name of Chilam Balam, a legendary author to whom are attributed 17th and 18th-centuries Maya miscellanies preserving much important knowledge. The Aztec civilization shared this image of the jaguar as the representative of the ruler and as a warrior. The Aztecs formed an elite warrior class known as the Jaguar Knights. In Aztec mythology, the jaguar was considered to be the totem animal of the powerful deity Tezcatlipoca.[63][112]
Contemporary culture
The jaguar and its name are widely used as a symbol in contemporary culture. It is the national animal of Guyana, and is featured in its coat of arms.[113] The flag of the Department of Amazonas, a Colombian department, features a black jaguar silhouette pouncing towards a hunter.[114] The jaguar also appears in banknotes of Brazilian real. The jaguar is also a common fixture in the mythology of many contemporary native cultures in South America,[115] usually being portrayed as the creature which gave humans the power over fire.Jaguar is widely used as a product name, most prominently for a British luxury car brand. The name has been adopted by sports franchises, including the NFL's Jacksonville Jaguars and the Mexican soccer club Chiapas F.C. The crest of Argentina's national federation in rugby union features a jaguar; however, because of a journalist error, the country's national team is nicknamed Los Pumas.[116] In the spirit of the ancient Mayan culture, the 1968 Olympics in Mexico City adopted a red jaguar as the first official Olympic mascot.[117]
Panthera onca
Jaguar range
Red: Current range
Bright pink: Former range
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