There are approximately 400 Sumatran tigers (Panthera tigris sumatrae) existing in the wild. Smallest of all the tigers, its stripes are narrower than in other tiger subspecies and it has a more bearded and maned appearance.
• They are generally very shy and seek to avoid people.
• They hunt wild boar and deer species, however will take other prey opportunistically.
• They are the smallest of the tiger subspecies, weighing up to 140kg.
• Bukit Tigapuluh, Kerinci Seblat and the Leuser ecosystems are the three global priority areas for tiger conservation.
Adult tigers are basically solitary animals that maintain relatively separate territories, however some overlapping occurs in tiger ranges. In general, the larger the range, the greater the overlap. Ranges of male tigers typically do not show any overlap, and males, by excluding other males from an area, ensure exclusive access to females for mating. For males, the critical resource is females, and each male's range usually encompasses the smaller range of two or more females.
The essentially solitary nature of tigers is reinforced by scent marks left throughout their territories to indicate presence and occupancy of the area. This scent marking is a passive form of defence, although fights do occur. The scent marks include urine sprayed on bushes and trees, faeces and urine left in prominent places, scratch marks on trees, and scrapes made by raking backwards with the hind feet. Both sexes routinely freshen scent marks, and the frequency of marking is higher in zones where contact with neighbouring tigers is likely. A tiger can tell whether a scent mark belongs to a familiar local resident or a stranger, a male or a female, and whether or not that female is in oestrus. Their loud vocalizations, called roars, probably help them to find each other.
Sumatran tigresses may come into oestrus throughout the year. Female oestrous cycles occur about every 30 days, and the female is receptive for about five to seven days during this cycle. During this receptivity, the female is extremely friendly toward the male, rubbing her body and face against the male until he attempts to mount. For the first few days, mounting attempts by the male are not successful. After this period, the pair copulates frequently every 15 to 20 minutes at a peak for five or six days. The male begins by grasping the loose skin of the female's nape in his jaws. Copulations last only 10 to 30 seconds, after which the female roars loudly, turns over on her back and lashes out at the straddling male with her paws, who has to leap clear to avoid injury. She then rolls vigorously on her back. They lay separately until the female initiates another bout. Finally they part. The frequent copulations are believed necessary to induce ovulation in the female.
Gestation is just over 100 days. Cubs are typically born in a secluded area central to the female’s home range. Up to five or six cubs may be born, but more commonly it is two or three. Only one or two cubs from a litter generally survive the first two years of life. Cubs are born blind and depend exclusively upon their mother for nourishment for the next five or six months. Their weight at birth is about 1.5 kg.
When the cubs are about six months old, they accompany their mother on her hunting expeditions so they can feed directly on the kill. In the following months, they will slowly learn how to hunt and kill their own prey. Male cubs grow faster than their female siblings and by one year of age are noticeably larger and more independent, sometimes spending the day away from the mother. By 16 months of age, tigers have fully developed canines, but they are not very efficient at killing prey. By 18 months of age, both sexes start making their own kills. At this age, males will leave to find their own territory. Females tend to stay longer with their mother. The father plays no part in the upbringing of the cubs. In fact, it has been suggested that he may be a danger to them.
The young male tiger faces his most challenging time when he leaves his mother and seeks to find his own territory. Resident males have been observed to tolerate subordinate males in their range, but in general, resident males exclude other males. Most young males are forced to live in less favourable habitat, biding their time until they can displace a resident male and gain their own territory. This usually occurs when the resident male gets too old or suffers severe injury.
Young females leave their mother's territory, usually when the mother comes into oestrus and becomes too aggressive. Sometimes, the mother allows one of her female cubs to settle in part of her territory. When that daughter becomes sexually mature, at around three years of age, she is likely to mate with her father. Other female cubs disperse further afield. During any female's lifetime, she will probably mate with a number of males, which is based on the male turnover rate within her range.
Tigers eat almost anything that moves, but in general, their most favoured prey are medium-sized deer and wild boar. They usually capture their prey by stalking to within short distances and charging the unsuspecting animal from the rear. Small prey are killed by a neck bite. Larger prey are grasped by the jaws and forelegs, and once pulled down, the tiger grasps its throat and throttles it. Tigers can kill prey as large as a buffalo weighing 200 kg. It may eat 20kg to 30kg at a stretch, feeding intermittently for several days on large carcasses until it is consumed.
Tigers, like all predators, are not successful in every hunt, missing their prey more often than they catch it.