After a gestation period of 16 weeks (about 3.5 months), a tiger gives birth to a live litter, usually comprising three or four cubs. However, litters of up to seven cubs have been known to occur, although they seldom all survive. In anticipation of her birth, the pregnant mother will prepare a den that is in a secluded spot; protected from other predators and from bad weather. These spots are often in crevices, caves, dense grasses or even in the hollow of a large tree and usually provide a mat of soft grass or leaves on which she can give birth. When the cubs are born, the female is alone; the father usually has nothing to do with the birth or rearing of his cubs. The cubs are born with their eyes closed and are, therefore, blind. They are totally dependent on their mother for their every need. Their eyes will open within between six and 12 days from birth. They weigh between 780 and 1 600 grams. If a litter of cubs dies for any reason, the female will be able to have another one within five months. The mortality rate of tiny tiger cubs is very high, and only about half of those born ever survive to reach maturity.
The mother will not readily leave her cubs unattended in the den for the first two months of their lives. If she needs to move them to a safer spot, she will carry them gently in her mouth by the scruff of their tiny necks. This is a marvellous thing, considering the sheer power of her potentially ruthless jaws and teeth.
In each litter, there is likely to be one dominant cub; usually a stronger, larger male (but, occasionally, this can be a female cub too). This cub will lead his ‘pack’ of siblings and dictate to them when they should sleep, play and eat. This cub will continue to dominate them until they leave their mother to become independent. He will eat more than them and be favoured by the mother. By nature, tiger cubs are playful and rather active. They will pounce on one another and chase blowing grasses or even their mother’s tail. They roll around with each other in mock fighting positions and leap through the tall grasses energetically.
The cubs drink milk from the mother until they are about two months old. In fact, nursing the cubs takes up about 70% of the mother’s time in those first few months. By six to eight weeks, they will begin to eat solid food. By about eight weeks, they will leave the concealment of their den and their mother will begin teaching them how to hunt for their own prey. At this stage, they will remain close to the proximity of the den, not yet ready to follow their mother as she goes in search of prey. This level of maturity only comes at approximately six months of age. The mother nurses the cubs until they are three to six months old, which coincides with the time at which they reach the maturity required to venture further afield with her in search of food.
Male cubs are more adventurous than their female siblings, which may account for the survival rate of females being higher. Major threats to young cubs include predators, fires and floods. As they get older and more adventurous, their threats change; and many are killed by being injured during their training for hunting.
To train the cubs to hunt, the mother will first perform stalks and kills as they look on. They will learn her technique and imitate her in later months and years. Then, she may bring down an animal, but not kill it; allowing the cubs to finish the kill before eating it. Only then will they begin to practice hunting on their own. They are usually accomplished hunters by the time they reach 18 months of age. Males and females will then leave their mother’s care at around 24 to 30 months of age. Females are likely to find personal territory close to their mothers, while her male cubs will probably wander further away from her.
The mother will give birth to a new litter approximately every two to 2.5 years.