JAGUAR
Panthera onca
STATUS:
The jaguar is a near threatened species and its numbers are declining. It is a protected species in the United States under the Endangered Species Act, which has stopped the shooting of the animal for its pelt.
DESCRIPTION:
The jaguar is the third-largest feline after the tiger
and the lion, and on average the largest and most powerful feline in the Western
Hemisphere. This spotted cat most closely resembles the leopard
physically, although it is of sturdier build and its behavioral and habitat
characteristics are closer to those of the tiger. The base coat of the
jaguar is generally a tawny yellow, but can range to reddish-brown and black.
The cat is covered in rosettes for camouflage in its jungle habitat. The spots
vary over individual coats and between individual Jaguars: rosettes may include
one or several dots, and the shape of the dots varies. The spots on the head and
neck are generally solid, as are those on the tail, where they may merge to form
a band. The underbelly, throat and outer surface of the legs and lower flanks
are white. The head is robust and the jaw extremely powerful. It has been
suggested that the jaguar has the strongest bite of all felids, and the second
strongest of all mammals; this strength is an adaptation that allows the jaguar
to pierce turtle shells. A comparative study of bite force adjusted for body
size ranked it as the top felid, alongside the clouded leopard and ahead of the
lion and tiger. It has been reported that "an individual jaguar can drag a 360
kg (800 lb) bull 8 m (25 ft) in its jaws and pulverize the heaviest bones".
SIZE:
There are significant variations in size: weights are
normally in the range of 56–96 kilograms (124–211 lb). Larger males have been
recorded as weighing 131–151 kilograms (288–333 lb) (roughly matching a tigress
or lioness), and smaller ones have extremely low weights of 36 kilograms (80
lb). Females are typically 10–20% smaller than males. The length of the cat
varies from 1.62–1.83 meters (5.3–6 ft), and its tail may add a further 75
centimeters (30 in). It stands about 67–76 centimeters (27–30 in) tall at the
shoulders. Further variations in size have been observed across regions
and habitats, with size tending to increase from the north to south.
POPULATION:
Given the inaccessibility of much of the species'
range—particularly the central Amazon—estimating jaguar numbers is difficult.
Researchers typically focus on particular bioregions, and 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 square kilometer (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 square kilometers (9,000 mi²), may have
465–550 animals. Work employing GPS-telemetry in 2003 and 2004 found densities
of only six to seven jaguars per 100 square kilometers in the critical Pantanal
region, compared with 10 to 11 using traditional methods; this suggests that
widely used sampling methods may inflate the actual numbers of cats.
LIFESPAN:
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.
RANGE:
The jaguar's present range extends from Mexico (with
occasional sightings in the southwestern United States) across much of Central
America and south to Paraguay and northern Argentina.
HABITAT:
The habitat of the cat 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; the cat has
lost range most rapidly in regions of drier habitat, such as the Argentinean
pampas, the arid grasslands of Mexico, and the southwestern United States. The
cat will range across tropical, subtropical, and dry deciduous forests
(including, historically, oak forests in the United States). The jaguar is
strongly associated with water and it often 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 3800 m, but they typically avoid mountain forest
and are not found in the high plateau of central Mexico or in the Andes.
FOOD:
Like all cats, the jaguar is an obligate carnivore,
feeding only on meat. It is an opportunistic hunter and its diet encompasses 85
species. The jaguar prefers large prey and will take deer, tapirs, peccaries,
dogs, and even anacondas and caiman. However, the cat will eat any small species
that can be caught, including frogs, mice, birds, fish, sloth, monkeys, turtles,
capybara, and domestic livestock.
BEHAVIOR:
Like most cats, the jaguar is solitary outside
mother-cub groups. Adults generally meet only to court and mate (though limited
non-courting socialization has been observed anecdotally) and carve out large
territories for themselves. Female territories, from 25 to 40 square kilometers
in size, may overlap, but the animals generally avoid one another. Male ranges
cover roughly twice as much area, varying in size with the availability of game
and space, and do not overlap. Scrape marks, urine, and feces are used to mark
territory. Like the other big cats, the jaguar is capable of roaring (the
male more powerfully) and does so to warn territorial and mating competitors
away; intensive bouts of counter-calling between individuals have been observed
in the wild. Their roar often resembles a repetitive cough, and they may also
vocalize mews and grunts. Mating fights between males occur, but are rare, and
aggression avoidance behavior has been observed in the wild. 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.
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% of its time active. The jaguar's elusive nature and
the inaccessibility of much of its preferred habitat make it a difficult animal
to sight, let alone study. It is also an apex and keystone predator, playing an
important role in stabilizing ecosystems and regulating the populations of prey
species. A short and stocky limb structure makes the jaguar adapt at
climbing, crawling and swimming.
OFFSPRING:
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. 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.
THREATS:
The loss of parts of its range, including its virtual elimination from its historic northern areas and the increasing fragmentation of the remaining range, have contributed to the status of "near-threatened" by the International Union for Conservation of Nature and Natural Resources. The major risks to the jaguar include deforestation across its habitat, increasing competition for food with human beings, poaching, hurricanes in Northern parts of its range, and the behavior of ranchers who will often kill the cat where it preys on livestock.
