Gestation (pregnancy) in meerkats takes 70 days (10 weeks). The female usually gives birth at night, in a burrow. The litters range from one to an average of 3-4 pups. The biggest litter observed had seven pups – even though meerkats have six nipples only.
The first four days are the most dangerous time in the life of a meerkat: Litters are often killed by other pregnant meerkat females, who want to raise the chances of survival for their own pups. Infanticides are less likely to occur after the first four days; strong females thus evict other pregnant females to keep their litters safe. Furthermore, babysitters stay with the pups to protect them. The pups’ eyes are closed before they leave the burrow. The pups are nursed by their mother, and in many cases, other females will also lactate to the pups, especially if they just aborted or lost their own litter.
Meerkat pups first emerge from their birth burrow at the age of 2-3 weeks. They weigh approx. 100 g at this stage. They will stay at the burrow, being guarded by babysitters. In most cases the group will move to another, clean burrow after the pups emerged, carrying the pups along. Pups are given their ID codes by the KMP researchers when they emerge; pups of habituated groups are not afraid of humans.
The pups start to forage with the group at the age of 3-4 weeks, and are gradually weaned while they get used to the meerkats’ prey of insects, scorpions and other small ground-dwelling animals. The pups’ gender can usually be established at the age of 1-2 months; pups are given personal names once their gender is established. The pups will dig for prey once they go foraging, but usually without much success; they instead follow helpers (older meerkats) and give loud begging calls, to which the helpers react by giving their prey to the begging pup.
Pups now have to learn to survive in the Kalahari: they learn to find and handle prey, and react properly to predators and other animals. Pups learn this with the help of older meerkats; they are first given dead and later immobilised prey, and finally live prey. The helpers thus adjust their “teaching” to the age or skills of the pups. Pups also learn to communicate, react to predator alarms with the adequate behaviour, or to mob intruders by observing older meerkats.
Begging pups are usually given food by older meerkats until they’re a few months old. The KMP classifies meerkats as pups until 3 months of age, as juveniles until 6 months, and as sub-adults until 12 months.
Male and female meerkats reach maturity around the age of one year. The female’s first oestrus seems to occur around the age of one year, though this is rarely observed. They often do not become pregnant until the age of two years, or else they abort, or their litters are killed by older females. However, early pregnancies occur – the youngest female to give birth was 9 months old. After reaching maturity, male meerkats start to join roving expeditions, often led by older, experienced males.
Yearlings also start to contribute to common tasks in the group, like babysitting or performing sentinel duty. Adult meerkats weigh approx. 600-800 g, but the maximum weighed for a non-pregnant meerkat was 1017 g.
Meerkats have a matriarchal social system and becoming the dominant female of a group is what all females inherently seek. The dominant female is the mother of up to 80% of the pups born in the family, and usually her offspring are protected and reared by all members. The dominant female often suppresses reproduction of subordinate females by evicting them, so that they abort or have to abandon their litters.
Males usually have to leave their native groups in order to find mating opportunities with non-related females. They can become dominant in other groups if they succeed in immigrating there and ousting the natal males. Dominant males will defend the group’s territory by scent-marking and fighting for it, always supported by the group. They will also defend the non-related females in the group from advances of other males. Subordinate immigrants thus often leave their new group after a while, and try to immigrate elsewhere. The KMP has observed male meerkats who lived in 5 groups, consecutively.
The average dominance span for a female meerkat is 31 months, while a dominant male holds his position for only 17 months on average. The maximum in the KMP for a female to hold dominance is 9.5 years.
The life span of a meerkat very much depends on its social position. Dominant meerkats in average live 6-10 years, with the maximum in the KMP being almost 13 years. Subordinate meerkats are in many cases evicted or disperse by the age of around 3 years, and are subsequently lost. The most important causes of death are predation, fatalities in fights with other meerkats (incl. infanticide), diseases, or human-caused factors like car fatalities – but for two thirds of the KMP meerkats the cause of death is unknown, since they just disappeared.