Because of the differences between the 8 different subspecies of Panthera tigris, the size in this animal varies. Those tigers that live in India average in weight between 286 - 575 lbs. Tigers that reside in Indonesia maintain lower weights that range from 220 - 330 lbs. Bali tigers are the smallest subspecies, ranging from 143 - 220 lbs. The largest subspecies, Siberian tigers, range from 220 - 675 lbs. Body lengths vary as well, ranging from 6 - 11 ft. The height from the ground to the top of the tiger's shoulder is about 35 - 40 in.

The tiger's body is built in such a way to aid in its hunting techniques. Longer hindlimbs than forelimbs are an adaptation for jumping, while strong and powerful forelimbs and shoulders aid in dragging down large prey. Like all cats, tigers have sharp retractile claws. These help this predator to hold onto its prey once the initial attack is made.

Another adaptation to hunting is the tiger's large and powerful jaw, which includes relatively flattened canines. The jaw's power makes the tiger's bite deadly. The stripes on a tiger act in the same way that a fingerprint does on a human. Each stripe pattern is unique to that particular individual.

The tiger is found in a variety of habitats: from the tropical evergreen and deciduous forests of southern Asia to the coniferous, scrub oak, and birch woodlands of Siberia. It also thrives in the mangrove swamps of the Sunderbans, the dry thorn forests of north-western India, and the tall grass jungles at the foot of Himalayas. Tigers are found in the Himalayan valleys, and tracks have been recorded in winter snow at 9,800 feet. The extinct Caspian tiger frequented seasonally flooded riverine land known as tugai, consisting of trees, shrubs, and dense stands of tall reeds and grass up to 10 feet in height. (When hunting in these reed thickets, tigers sometimes reared up on their hind legs or leaped upward in order to see their surroundings.) The tiger’s habitat requirements can be summarized as: some form of dense vegetative cover, sufficient large ungulate prey, and access to water.

Biomes: taiga, temperate forest & rainforest, temperate grassland, tropical rainforest, tropical deciduous forest, tropical scrub forest, tropical savanna & grasslands

Palearctic, Oriental: India, Manchuria, China and Indonesia. These mysterious mammals were once found in the regions of Afghanistan, Pakistan, Iran and other parts of Indonesia.

For tigers that live in the tropical forest region, breeding activity has been recorded throughout the year; however, in the northern regions breeding has only been observed in the winter months. A female is only receptive for a few days, and mating is frequent during that time period, possibly reaching 100 copulations during only two days. The male is able to tell when a female is in heat, which decreases any incidences in which an unreceptive female is pursued. A male tiger mates with all the females within his home. The gestation period is 103 days. A typical litter is about 3 - 4 cubs in size, each blind and helpless and weighing about 2 lbs. Rearing of the young is done by the female. In the beginning she needs only to suckle her young, but as they become older and begin to grow more rapidly she must hunt more often to find enough food to sustain both herself and the cubs. One of the reasons a female's home range is smaller than that of a male is because females must stay as close as possible to their young so that they can return to the den often to suckle them. At about 8 weeks of age, the cubs are ready to follow their mother out of the den and become familiar with their surroundings. The cubs begin to gain their independence around 18 months of age, but it is not until they around 2 - 2 1/2 years old that they go off in search of their own range. The cubs reach sexual maturity by 3 - 4 years of age.

The main source of food for tigers is large, hooved mammals, but they will eat anything they can catch. Where wild prey is scarce, tigers will readily prey on livestock if it is available. The moderately dense covering in which tigers and their prey live aids in the success of their hunting technique. Tigers are stalk and ambush predators, and they use the dense covering to conceal themselves and sneak up on their prey. When the tiger is close enough to its prey, it suddenly rushes at it and attempts to kill it. Only 1 in 10 or 20 attacks is successful. The tiger uses its powerful body to knock the prey off balance. The attack is normally made from the side or rear of the victim, and the objective is to get the prey off of its feet and to deliver a fatal bit to the back of the neck or throat. The tiger may keep his grip several minutes after death. When the tiger is ready to begin eating its kill, it drags the carcass into a dense covering and begins eating the rump. A considerable amount of meat can be consumed at one time (45 - 75 lbs), however, if the kill is to sustain an individual over several days, the amount eaten is generally less (33 - 40 lbs/day). Female tigers with young have to kill more often to feed their young and themselves as well.

In general, the social system of the tiger is not very complex. The mother and her young are the basic social unit. Tigers generally hunt alone; however, there have been instances when a high degree of social tolerance has been demonstrated. Sometimes tigers are seen in groups in the wild at bait kills, as well as in zoos occupying the same exhibit.

Generally, both female and male tigers maintain home ranges that do not overlap with the home range of another tiger of the same sex. Tigress home ranges are approximately 12 square miles while the ranges of males are much larger, covering 37 - 60 square miles. Male home ranges cover the territory of many smaller female home ranges, and those females make up a sort of harem for that male. He must protect his territory and the females within it from competing males. Because it is impossible to be at several places within a home range at one time, tigers use several kinds of signals to communicate a wide spectrum of information. The two main senses used in interpreting these signs are smell and sight. Urine and anal gland secretions are sprayed on trees, bushes and rocks in various places throughout a particular area, as well as feces and scrapes. The information that these signals contain is very useful in reducing physical conflict with neighboring animals. Tigers learn to interpret these signals and perhaps to avoid a particular area because they recognize the scent of another tiger. Males use a behavior called "Flehmen" to determine a female's reproductive condition. This behavior, which includes a characteristic grimace, involves smelling the female's urine to determine if she is in heat.

Male tigers may kill a mother's cubs if the cubs are the offspring of a previous male. This ensures that the female will come into heat and bear the new male's offspring.

Every subspecies of Panthera tigris is endangered. The wide geographical range could mislead people into thinking that tigers are highly adaptable, but in fact this species is very specialized and requires a particular type of habitat, which is being encroached upon for agricultural purposes. This type of land is a habitat for many large-hooved mammals, which are the bulk of the tiger's diet. Also, most existing tiger reserves are small in size and isolated, and it is rare that interbreeding occurs between different populations. This results in inbreeding, which may cause a problem in the future.

There are 8 different subspecies of Panthera tigris , one of which is the Siberian tiger (P. t. altaica). This subspecies is the largest living felid, and the record weight for this animal is a male weighing 846 lbs. There were only 200 of these animals left in the wild as of 1987. Another subspecies is the Javan tiger (P.t.sondaica); there are only 3 - 4 left in the wild. Two subspecies, South Chinese tiger (P. t. amoyensis) and Caspian tiger (P. t. virgata) may be extinct, and the subspecies called the Balinese tiger (P. t. balica) is now probably extinct.

Brakefield, Tom. Big Cats: Kingdom of Might. Stillwater, MN: Voyageur Press, 1993

Alderton, David. Wild Cats Of The World. New York: Facts on File, 1995

Nowak, Ronald. Walker's Mammals Of The World. Baltimore: Johns Hopkins University Press, 1999