Survival of the Fittest

Social organization among tigers varies with the quality of habitat in a given area, the determinant of quality being the abundance of prey and optimum hunting cover. In a high prey density area the territorial definition of land tenures is prominent. In such an area the dominant males occupy very extensive territories as large as 20 to 40 sq miles. Up to three or even five females occupy mutually exclusive sub-territories within a large male territory. The females in such an organization are assured of food supply for themselves and their progeny and in turn owe allegiance to the territorial male. This also affords protection to their cubs from rival males as the territorial male meticulously demarcates and guards his territory against rivals. Such a high prey density area in a region thus serves as the main natal area with most of the breeding taking place there.

The young cubs stay under the care of the mother for anything from 1 ½ to 2 ½ years where after they are compelled to leave the natal area. But a young tiger is seldom able to find a place in the adjacent medium- prey-density areas because of their firm occupation by either the past prime adults recently thrown out from the natal area or the pre-prime adults preparing to find a foothold there. Thus a young tiger dispersing from the natal area may be required to travel far and may in fact remain transient in the low -prey-density peripheral area for a long time.

Males demarcate their territory by spraying scent with their urine on prominent trees in their territorial boundaries. They also often deposit their scent on the underside of the drooping branches of low bushes. This way the scent lasts longer preserved from excessive evaporation or from being washed away by rain. Another and simultaneous way of marking territory is to make scrapes on the ground and tree trunks with the paws and then to deposit a foul smelling secretion from the anal gland. These markings are intelligible to the other tigers and are recognized. Territorial integrity is maintained by frequent patrolling.

The females also mark their territories in the same manner but not as frequently or meticulously. The intensity of scent markings by a female becomes very high when she is in estrus and ready to have a mate. Her physiological condition is advertised by this scent and helps attract the males. The courtship period usually spreads over a week or 10 days but the actual mating period may be only two to three days during which copulation is frequent. Such association of the courting pair is necessary among cats in whom ovulation is promoted by frequent copulation. The gestation period in the case of the tiger is short being about 105 days. Since the tigress even during the terminal days of her pregnancy has to hunt for herself, nature has ensured that her pregnancy does not disable her from doing so. It is for this reason that the gestation period is so short the fetal size at birth small and the stage of development of the cubs when they are born rather low.

Both the Males and the females occupying the natal area are prime members of a population. Therefore confrontations take place among dominant tigers particularly males in order to establish supremacy and possess a territory. Such confrontations may range from a skirmish to serious figth, depending upon the match between the contenders. All out fights are by no means uncommon and very serious and deep wounds may be sustained. Wounds may not heal and may eventually cause death after a few days or even weeks. However tigers are generally able to heal all their wounds by licking them. Where direct licking is not possible they manage to reach the spots and such occupancy of prime habitats by prime adults is indeed a corollary to the axiom survival of the fittest. This ensures that only the best animals of both sexes are able to breed.