The Tiger (Panthera tigris) is the largest species of cat living on planet Earth today and is part of the Felidae family and a member of the Panthera genus.
In the wild, the territory of the tigers has been drastically reduced in the last century and they can be found today only in the Siberian taiga and in open grasslands and tropical mangrove swamps.
The tiger is classified today as endangered by the IUCN Red List because the population has been reduced from 100.000 at the beginning of the 20th century to a number of almost 4,000 today, mostly due to habitat fragmentation and loss, and also due to poaching.
The genetic studies have indicated that about 2,88 million years ago, the snow leopard and the tiger diverged from the other species of Panthera and they are more related to each other than with the African lion, the leopard and the jaguar.
Today’s tigers have a common ancestor called Longdan tiger (Panthera zdansky) that lived in northwestern China about 72,000 to 108,000 years ago.
There are several subspecies of tigers living today on the Asian continent and also in Sunda islands.
Tiger subspecies living today in continental Asia.
1. Bengal tiger (Panthera tigris tigris): is considered the largest subspecies of tiger living today because males reach a total length from nose to tail between 110 to 120 inches (270 to 310 cm) and a weight between 397 and 569 lbs (180 to 258 kg).
Some of the largest specimens reached a length of 153 inches (390 cm) and over 300 kg (660 lbs) in weight.
Females are smaller, reaching a total length between 94 to 104 inches (240 to 265 cm), and a weight between 220 to 350 lbs (100 to 160 kg).
The colour of the Bengal tiger is light yellow to reddish yellow and has black stripes.
These are the largest members of the species (they are larger than the African lions) and inhabit today the alluvial grasslands, subtropical and tropical rainforests, wet and dry deciduous forests, scrub forests and mangrove habitats in Nepal, India, Bangladesh and Bhutan.
2. Siberian tiger (formerly Panthera tigris altaica, and today Panthera tigris tigris):
This is a heavy tiger because it features a thick coat (required in its cold habitat) with pale hues and dark brown stripes.
Males reach a length between nose and tail of 98 to 133 inches (250 to 340 cm), and a weight between 397 and 675 lbs (180 and 306 kg), while the females are smaller, reaching a total length between 86 and 114 inches (220 and 290 cm), and a weight between 220 and 368 lbs (100 to 167 kg).
These tigers can be found today in Russia (Siberian region) and in northeastern China (in the Hunchun National Siberian Tiger Nature Reserve).
3. Caspian tiger (formerly Panthera tigris virgata, and today Panthera tigris tigris): this is an extinct subspecies of tiger that lived by the late 20th century in Eastern Anatolia, South Caucasus, the coasts of the Caspian and the Aral Seas, in Central Asia in the basins of the Amu-Darya and the Syr-Darya rivers, the Altai Mountains and in the southern shore of Lake Balkhash (a large lake in Central Asia).
This was a pretty large tiger (between the Bengal tiger and the Siberian tiger after the size of the head), and was closely related to the Siberian tiger, but with a coat that was briighter and more uniform compared to the coat of the Siberian tiger.
4. Indochinese tiger (formerly Panthera tigris corbetti, and today Panthera tigris tigris): this is a smaller tiger compared to the Bengal tiger because males reach an average length from nose to tail of only 108 inches (270 cm) and a weight between 331 and 430 lbs (150 to 195 kg).
Females are even smaller, reaching an average length of 96 inches (240 cm) and a weight of only 220 to 290 lbs (100 to 130 kg).
This is a tiger with a coat that is yellow to orange in color with black stripes, and lives today in Thailand, Myanmar and Laos.
5. South China tiger (formerly Panthera tigris amoyensis, and today Panthera tigris tigris): it is considered the most ancient species of tiger due to its narrow skull and long-muzzled nose.
Its coat is orange in color and features rhombus-like black stripes.
Males can reach a length between 91 and 102 inches (230 to 260 cm), and a weight between 290 and 400 lbs (130 to 180 kg).
Females are smaller reaching a length of only 87 to 94 inches (220 to 240 cm), and a weight between 100 and 110 kg.
The population of South China tiger is extinct in the wild today, but the captive population consists today of more than 70 individuals.
6. Malayan tiger (formerly Panthera tigris jacksoni, and today Panthera tigris tigris):
There is no major difference between the Malayan tiger and the Indochinese tiger in terms of skull size or pelage, but it was proposed as a distinct subspecies after the genetic studies that showed a difference in their DNA.
This is a pretty small tiger because males reach a length from nose to tail of only 75 to 110 inches (190 to 280 cm), and a weight between 104 and 285 lbs (47 to 129 kg), while the females are even smaller, reaching a length of only 71 to 102 inches (180 to 260 cm), and a weight between 53 and 194 lbs (24 to 88 kg).
The Malayan tiger population consist today of about 200 adult individuals that live in southern and central regions of the Malay Peninsula.
Tiger subspecies specific to the Sunda Islands.
1. Javan tiger (Panthera tigris sondaica).
The Javan tiger is an extinct subspecies of tiger that lived in the Indonesian island of Java (the last specimen was hunted in mid 1970s).
Compared to other subspecies of tiger, the Javan tiger was a smaller cat, males reaching a total length of only 98 inches (248 cm) and a weight of 220 to 311 lbs (100 to 141 kg), while the females were smaller, reaching a total length of about 86 inches (220 cm), and a weight between 165 and 254 lbs (75 to 115 kg).
2. Sumatran tiger (formerly Panthera tigris sumatrae, and today Panthera tigris sondaica).
This tiger still lives today in the Indonesian island of Sumatra, and is the smallest subspecies of tigers.
Males reach a length from nose to tail of 87 to 100 inches (220 to 255 cm), and a weight between 220 and 310 lbs (110 to 140 kg).
Females are smaller, reaching a total length of 85 to 91 inches (215 to 230 cm).
The Sumatran tiger population is the last surviving tiger population among all the three Indonesian island populations of tigers.
In the wild there are about 441 to 679 adults today, and they live in 10 protected areas that cover an area of 20,000 square miles.
3. Bali tiger (formerly Panthera tigris balica, and today Panthera tigris sondaica).
This is also a smaller tiger that lived in the Indonesian island of Bali.
Due to excessive hunting, the Bali tiger is today extinct (the last adult tiger, which was a female, was hunted in West Bali on 27 September 1937).
A typical feature of this tiny tiger was the skull that had a narrow occipital plane.
Males reached a total length of 87 to 91 inches (220 to 230 cm), and a weight between 200 and 220 lbs (90 to 100 kg), while females were smaller, reaching a length of 75 to 83 inches (190 to 210 cm), and a weight of 143 to 176 lbs (65 to 80 kg).
Tigers are today the largest members of the Felidae family because both males and females are larger than the lions.
Male tigers can reach a total length (from nose to the end of the tail) that varies between 90 and 153 inches (250 to 390 cm), and a weight between 198 and 675 lbs (90 to 306 kg).
The tiger is a muscular and very agile cat, with a large and robust head, large and massive paws with sharp and powerful forelimbs.
Its coat is dense and heavy with colors that can vary from orange and light brown to yellow and white ventral areas, and also with distinctive vertical black stripes.
The skull of the tiger is similar in size and shape with the skull of a lion, and the only difference can be seen in the shape of the lower jaw.
The canines are very large and curved, and they can reach a height of height of up to 3.5 inches (90 cm).
Males have a mane-like heavy growth of fur that surrounds the neck and jaws with long whiskers.
The eyes have round pupils with yellow irises, and the ears are small and rounded, and feature a prominent white spot on the back of the ear, which is surrounded by black fur.
These fake eyes are called ‘ocelli’, and they seem to have an important role in the communication among species.
Tiger Behavior and Social Organization
Adult tigers live generally solitary lives, and they have established territories that can cover an area of 20 square miles for females and 23 to 40 square miles for males.
Even if they prefer to live solitary, the territory of a male tiger can overlap over several female territories, which will allow the male to have a wide prospective for mating partners.
Some tigers can disperse over large distances of up to 400 miles (650 km), just to reach other tiger populations.
Male tigers are more aggressive defending their territory against other males compared to the females that could allow other females to cross their territory.
However, when eating a kill, a tiger can allow other tigers to join the feast.
This way, a male tiger can allow a tigress with cubs to feed from its kill.
In very rare cases, male tigers can participate in raising their own cubs.
Tigers are very good swimmers, they can swim in rivers, lakes and ponds.
A tiger can swim long distances per day (18 miles or 29 km).
They can even catch and carry prey through water.
Tigresses reach sexual maturity at the age of three to four years, while the males at the age of four to five years.
Mating is more common between the months November and April, but it can occur all year long.
Gestation can range from 93 to 112 days (an average being 103 to 105 days), and the newborn cubs (up to three cubs and extremely rarely six) will be very tiny compared to their mother, because they weigh only 1.50 to 3.09 lbs (0,68 to 1,4 kg).
The female will provide them with milk up to the age of five to six months.
Wandering males that are unrelated with the female can occasionally kill the cubs to make the female receptive again.
If the cubs are lost, the tigress will give birth to another litter within a period of five months from the previous litter.
Around the age of six months, the cubs will start roaming the territory along with their mom, and they will be taught to hunt.
A tiger cub is capable of hunting around the age of eleven months, and it will become independent at the age of eighteen months.
However, cubs will completely separate from their mother at the age of two to two and a half years.
A very large population of tigers has been hunted or lost due to habitat fragmentation and loss in the 20th century, but the efforts to recover the tiger population made in this century have managed to increase the number of tigers in the wild from 3,200 individuals in 2011 to 3,890 individuals in 2015.
India is home for the largest population of wild tigers in Asia (2,226 individuals at a census made in 2014) mostly due to the increased number of tiger reserves and due to the laws to reduce poaching.
Wild tigers can be found in many Asian countries on the continent, but also in the Sunda islands, and also in captivity in many areas of the planet.
Even so, because poaching was not entirely eradicated in the countries that are home for the tigers, their population is still in danger, and this is the reason why the IUCN Red List marked the tiger as endangered species.