The bull will follow the female and she will run away. This behaviour will attract other bulls and when a big male in Musth reaches, she will allow him to catch her and they will mate. Typically they stay together for three or four days, in this period they will mate a few times and the bull chases the other competitiours away. The number of cows coming oestrus can change dramatically under different conditions. According to a drought C. Moss has found during two years in Amboseli NP only one cow in oestrus, in the next year it were more then 100.
Elephants react to environmental conditions and decrease mating when overpopulated.
Due to the ban of ivory trade poaching has decreased considerably. The major problem now is the increasing human population. Areas used since eaons of time from elephants are developed to farmland and the farmers can't afford loosing their crop in one night to a hungry elephant group. On the long run elephants and humans can't coexist in the same area and the elephants are driven. National Parks can'solve that problem.