Pandas are very choosy about their mates. The females are only receptive for a few days. During this time, if she is unable to find any willing mate then the reproductive opportunity is certainly lost. These animals reach the maturity age after five or seven years. Besides, females litter 1 – 2 cubs which seldom survive in the wild. The weight of these cubs is no more than 4 – 8 ounces which further makes their survival difficult.