Tiger

A tiger’s stripes are not just on its fur. Shave a tiger and the pattern is still there, printed on the skin underneath.

Every tiger’s stripes are unique, like a fingerprint, and researchers identify individual wild tigers from camera-trap photographs by the pattern on their flanks.

The tiger is the largest cat in the world. It is also one of the rarest, and there is a genuinely uncomfortable statistic attached: more tigers live in cages in the United States than survive in the wild anywhere on Earth.

The tiger’s scientific name is Panthera tigris.

• Kingdom: Animalia
• Phylum: Chordata
• Class: Mammalia
• Order: Carnivora
• Family: Felidae
• Genus: Panthera
• Species: Panthera tigris

Being in Panthera makes the tiger a true big cat alongside the lion, leopard and jaguar, and means it can roar. A tiger’s roar carries up to 2 miles.

Several subspecies survive, including the Bengal, Siberian, Indochinese, Malayan and Sumatran tiger. Three are already gone: the Bali tiger, the Javan tiger and the Caspian tiger, all lost during the twentieth century.

For camouflage, and it works far better than it looks in a zoo.

Orange looks conspicuous to us, but the animals a tiger hunts do not see color the way we do. Deer and wild boar are red-green color blind, so to them an orange tiger reads as a dull greenish gray. Add vertical black stripes and the cat dissolves into tall grass and broken shadow.

A tiger can lie 50 feet from a deer and remain invisible until it moves.

The stripes do a second job. Because every pattern is unique, they identify individuals, and conservationists rely on this: a camera trap photograph is enough to tell one wild tiger from another and count a population without ever touching an animal.

And the pattern goes all the way down. The stripes are pigmented into the skin itself, not only the hair growing out of it.

Tigers measure 5 to 10 feet in the body, with a tail of around 3 feet, and weigh 140 to 660 pounds. Siberian and Bengal tigers are the largest; Sumatran tigers are much smaller, which suits dense forest.

• Canine teeth. Up to 3 inches long, the largest of any living cat.
• Paws. Broad, with retractable claws up to 4 inches. A single swipe carries enough force to break bone.
• Night vision. Around six times better than ours, thanks to a reflective layer behind the retina.
• Hind legs. Longer than the front legs, which gives the tiger its forward-leaning stance and lets it leap 30 feet.
• Tongue. Covered in backward-facing barbs rough enough to scrape meat off bone.

White tigers are not a subspecies and not albino. They are Bengal tigers carrying a rare recessive gene, and every white tiger in captivity descends from a small number of closely related animals, which is why so many have health problems.

Tigers live only in Asia, across India, Nepal, Bhutan, Bangladesh, Myanmar, Thailand, Malaysia, Indonesia, China and the Russian Far East.

They use an extraordinary spread of habitats: tropical rainforest, dry forest, grassland, mangrove swamp and snowbound Siberian taiga where winter falls below minus 30.

What they need is cover, large prey and water. Tigers drink often and swim readily, unlike most cats, and will cross rivers and swim several miles.

They have lost more than 90 percent of their historic range, which once reached from Turkey to the Russian coast and south through Indonesia.

Tigers are carnivores, hunting deer, wild boar, antelope and water buffalo, with smaller animals taken when large prey is scarce.

They hunt alone, by stalking. A tiger creeps to within about 30 feet, then rushes, and kills large prey with a bite to the throat.

Most attempts fail. Perhaps one hunt in ten or twenty succeeds, so a tiger may go several days between meals and then eat up to 80 pounds at once, covering the rest of the carcass and returning to it.

That poor success rate is why prey numbers matter so much. A forest can look perfect and still hold no tigers if the deer have been hunted out.

Tigers are solitary and territorial, which sets them apart from lions. Each holds a range it marks with scent, scratched trees and calls, and a male’s territory may overlap several females.

They are mostly active at night and around dawn and dusk.

They are strong swimmers and genuinely enjoy water, lying in rivers and pools to cool off, which almost no other big cat does.

They cannot purr. Instead a relaxed tiger makes a friendly huffing sound called a prusten, blown through the nostrils, used between tigers that know each other.

They also produce infrasound, too low for us to hear, which travels through dense forest and may be part of how they communicate across distance.

Pregnancy lasts about 103 days and produces two to four cubs, born blind in a den among rocks or dense vegetation.

The mother raises them entirely alone. She hunts while they wait hidden, which is the most dangerous period of their lives, and roughly half of all cubs die before reaching two.

Cubs start following her at around two months and learn to hunt by watching. They stay with her for two years, which is a long apprenticeship for a solitary animal.

Tigers live 10 to 15 years in the wild and over 20 in captivity.

An adult tiger has no natural predators. Cubs are taken by other tigers, leopards, bears, dholes and crocodiles.

Every serious threat is human. Poaching is the worst: tigers are killed for skins and for bones and body parts sold in traditional medicine, and a single tiger is worth a great deal to a criminal network.

Habitat loss and fragmentation break populations into pockets too small to stay healthy. Prey depletion empties forests that still look intact. And conflict kills tigers directly, because a tiger that takes livestock near a village rarely survives long.

The tiger is Endangered, with roughly 4,000 to 5,500 left in the wild.

For context, there were perhaps 100,000 tigers a century ago. The low point came around 2010, when the wild population was estimated at about 3,200.

Here is the good news, and it is real. Numbers have risen since that low point, the first sustained increase in a century, driven by hard protection work in India, Nepal, Bhutan and Russia. Nepal roughly tripled its tiger population. India holds the large majority of the world’s wild tigers.

The captive figure is the strange part. Estimates suggest around 5,000 tigers live in captivity in the United States alone, more than the entire wild population, most of them in private hands rather than accredited zoos and contributing nothing to conservation.

As the top predator across Asian forests, the tiger controls deer and wild boar numbers, and that matters more than it sounds. Unchecked deer strip undergrowth and young trees, and a forest grazed bare regenerates poorly.

Tigers also change where prey dares to feed, which spreads grazing pressure around rather than concentrating it.

Because a single tiger needs a very large area with healthy prey, protecting tigers means protecting whole landscapes. Tiger reserves in India shelter elephants, leopards, sloth bears, hundreds of bird species and the watersheds that supply water to millions of people downstream.

That is the argument for tigers that has nothing to do with how magnificent they are: saving them saves a great deal else by default.