More tigers now live in cages than in the wild

Tigers are secretive, solitary animals that need a lot of room to move. From lush jungles in Malaysia and Indonesia to high mountains in Bhutan and mangrove forests in India, the habitats tigers roam in search of food are being lost to deforestation and development. Much of what remains is fragmented into chunks of isolated forest surrounded by roads, farms, towns and cities.

With their sleek, stripey coats, piercing stare and adorable cubs, tigers are highly sought-after as exotic pets and zoo animals. This is especially true in the US — according to the US Fish and Wildlife Service, the total number of tigers in the country "likely exceeds the numbers found in the wild." It's estimated there could be from 2,000 to 5,000 tigers living in the state of Texas alone.

Only half of tiger cubs survive in the wild. Mothers may refuse to feed their offspring or abandon them for unknown reasons. In captivity, zoos have overcome this by getting female dogs to takeover the feeding of tiger cubs. The dogs don't seem to know the difference between their own offspring and the tiger cubs, which take around the same amount of time to wean.

There are nine subspecies of tiger, of which six survive today. The differences are mostly a reflection of extreme climatic changes over thousands of years. The Siberian — or Amur — tiger (pictured), for example, is bigger and hairier than other subspecies. This means it can retain heat in the frosty Siberian wilderness, as it has a smaller surface area relative to its overall mass.

While the six surviving tiger subspecies don’t have a lot of genetic variation, they are each uniquely adapted to their habitats — which are in Asia, not Africa. Some live in tropical forests, others in dry forests, some in marshes and wetlands and some at elevations of 3,000 meters (10,000 feet). That makes it more difficult to relocate them to different parts of the world to boost numbers.

Although far from being the only issue facing the great cat, climate change poses a major threat to their habitat. A recent study, published in Science of the Total Environment, predicted that sea level rise in the Sundarbans — a mangrove forest stretching across India and Bangladesh — will likely decimate the local Bengal tiger population, the only subspecies adapted to living in mangroves.