Sexual Maturity and Breeding Season
Young female collared peccaries become sexually mature 33-34 weeks, whereas young males are ready to produce offspring 46-47 weeks after birth (Texas Tech University, 1997). Once sexually mature, female collared peccaries enter the estrous cycle more than once in a single breeding season, staying therein for about 24 days, with actual estrus lasting about four days. For this reason, breeding can occur at any time in the year. However, exceptions to this rule exist, as peccaries in Arizona breed during February (McCulloch, 1955, cited by Neal, 1959), whereas those in Texas have their mating season in December (Jennings and Haris, 1953, cited by Neal, 1959).
Mating System and the Acts of Courtship and Mating
Collared peccaries have a promiscuous mating system, as no pair bonds are formed after mating. Females usually allow the male to assume the dominant role in courtship and mating, although males can be passive in some cases (Byers and Bekoff, 1981). Lending more evidence to the hypothesis that a dominance hierarchy does not exist in these creatures (see "Social Behavior"), Byers and Bekoff observed only mild agonistic behavior among male peccaries competing for sexually receptive females, and they failed to see any fighting. Though females will drive off a male who attempts to interrupt mating between her and another male, they have been known to mate with more than one male in one instance, but without hostility between the two males (Byers and Bekoff, 1981). One may draw the conclusion that the sperm of male peccaries is competitive, and that the fertility of male peccaries ensures the production of their own offspring, since there is little to no hostility between male peccaries concerning females in estrus.
Offspring
Following impregnation, the gestation period lasts about 145 days (Sowls, 1984, cited by Novak, 1999). When the female peccary gives birth, she usually has two offspring, but her litter size can range from one to, on rare occasions, four offspring (Novak, 1999). The nest is usually an abandoned burrow, log, or cave that served as another animal’s habitat before the female peccary discovered it (Novak, 1999). Newborn peccaries weigh about 500-900 g in their first five days, quickly growing to about 3 kg at one month old (Lochmiller et al., 1987). Due to high predation risk, peccary piglets are capable of running behind their mothers only a few hours after birth. Another adaptive behavior of peccary young is their defensive temperament directly inherited from their parents, which is exhibited when young peccaries employ their teeth as weapons against human researchers when approached (Neal, 1959). An infant peccary, however, is a diminutively sized creature, so it must stay with its mother. Though the mother is the one primarily responsible for rearing its young, males may lend some help in caring for the progeny. No adults exhibit hostility towards young, and they allow the piglets to intermingle with them. Young peccaries stay with the herd at all times, mostly feeding with their mothers for the first two tot three months of their lives (Neal, 1959).
This website was completed in partial fulfillment of the requirements for Biology 323, Animal Behavior, at Davidson College in the spring Semester 2008.
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