Can the problems associated with the low reproductive rate in captive white rhinoceroses (Ceratotherium simum) be solved within the next 5 years?

The reproductive rate of the white rhinoceros in captivity is very low and >50% of animals are >20 years of age. At a recent IRF (International Rhino Foundation) workshop reproductive problems have been defined as 1) acyclicity and variable oestrous cycle length of 35 or 70 days, 2) mating failure due to acyclicity, or silent oestrus due to sibling relationship/mate choice problems and 3) conception - pregnancy failure due to presumed uterine pathology. Although reasons for any of the above problems could not be identified definitively, possible solutions are available. Serial faecal reproductive monitoring will help to evaluate effects of management measures. The most promising recommendation is to transfer animals between zoos in order to break up sibling relationships/overcome mate choice problems. The additional use of diagnostic ultrasound for reproductive assessment is strongly encouraged. Serial ultrasound examinations would be best, however, even single ultrasound exams will provide invaluable contributions to the understanding of white rhino reproductive failure. Other options are to work on protocols for ovulation induction in animals with missing or erratic luteal activity and to continue research into the development of artificial insemination.