Observations on Reproduction and Breeding Behavior of the African Elephant

Observations on the breeding behavior of the African elephant (Loxodonta africana) in Uganda show that some wild females begin to breed at approximately 7 years and all females breed by approximately 11 years of age. A declining population and lower annual increment of elephants south of the Victoria Nile River in Murchison Falls National Park are associated with an average postpartum preconception interval more than three times longer than the 24.1-month (sic) period reported in 1953 by Perry. The change in length of this interval is possibly a function of self-regulation in population numbers. At least in some parts of its range, the wild African elephant breeds throughout the year with no distinct seasonal acceleration. Corpora lutea present during early pregnancy are not replaced during a subsequent stage of pregnancy but are maintained throughout gestation and for about 2 months after parturition. Old or degenerate corpora lutea persist for at least 4.5 years postpartum. Apparently in some animals corpora lutea develop before conception, whereas in others, conception apparently occurs when corpora are established. At least two graafian follicles may ovulate and develop into corpora lutea within a short time. Cows have multiple mates, there is no prolonged male-female relationship, and frequently there is no fighting by bulls over females. Information concerning breeding and reproduction of the African elephant is limited. One of the most extensive reports directed entirely to various aspects of reproduction of the African elephant is that of Perry (1953). His study is devoted largely to describing the female reproductive tract, and emphasizes ovarian characteristics. Recently, Johnson (1963) reported extensively on histological and quantitative characteristics of the testes of the African elephant. He includes observations on the teeth and pituitary gland, and presents evidence that suggests the possibility of individual cyclicity in reproductive activity of adult males. Short and Buss (1965) detected no progesterone in 11 corpora lutea from six African elephants in various stages of the estrous cycle and pregnancy, postulated a relatively short functional and long structural life of the elephant's corpus luteum, and suggested that some corpora lutea developed prior to conception. The first three chapters of a monograph by Hill et al. (1953:11-67) on the elephant in East-Central Africa include general information on reproduction. The anatomy of the male reproductive system has been reported on by Mojsiscovics (1879), Oudemans (1892), and Schulte (1937). Data on age at sexual maturity and duration of gestation are provided by Seth-Smith (1932), Hundley (1934), Burne (1943), and Flower (1943). The African elephant breeds throughout the year, at least in those areas for which data are available. Krumbiegel (1943) and Ansell (1960) observed calves throughout the year. Perry (1953) noted fetuses of variable age in cows collected throughout the year in Uganda. Buss and Brooks (1961) and Buechner et al. (1963) found no evidence of seasonal peaks in parturition and concluded that breeding occurs throughout the year in Uganda. Considering that environmental conditions within the African elephant's extensive range are highly variable, and that information has been secured from a limited part of this range, the possibility of seasonal breeding in some areas cannot be ruled out. The purpose of this study was (1) to study structures of 120 pair of ovaries from