Females are reproductively receptive for about three weeks, but conception is only possible three to five days of that time.
Reproductive receptiveness is often displayed in females by greater interest and enthusiasm at the approach of a musth bull and/or exhibit an estrous walk. Receptive females may also exhibit an estrous walk, characterized by holding their head held high and frequently looking over their shoulders. Estrous females (reproductively receptive) will also vocalize at this time. These sounds travel long distances and help distant musth bulls locate the female.
Competition for potential mates is settled by bulls through a trial of strength, usually pushing, tusking, wrestling, and ramming. The weaker of the two bulls is forced to retreat and gives up mating rights to the female. Rarely do these mating fights turn brutal, as they are a quick assessment of strength and virility.
Males assess a female's reproductive status by testing her urine for hormones. Chemical information is picked up through the trunk, blown into the roof of the mouth, and then detected by the Jacobson's organ in the upper palate of the mouth.
Refer to the Senses section - Olfactory.
Successive mating occurs briefly from a few hours to four days. Males usually stay with the female after mating to prevent her from mating with other males.
Both African and Asian elephants have a gestation period of almost two years (20-22 months).
By the third month of pregnancy, the calf's ears, trunk, and tail are present.