Fewer than 80 Sumatran rhinos survive in very small and highly fragmented populations. The Sumatran rhino is the most endangered of all rhinoceros species due to its rapid rate of decline. Because of poaching, numbers have decreased more than 70% over the last 20 years, with the only viable populations now in Indonesia. The species was declared extinct in the wild on mainland Malaysia in 2015 and Malaysian Borneo in 2019. Sumatran rhinos exist only in protected areas where they are physically guarded by Rhino Protection Units (southern Sumatra) and Wildlife Protection Units (northern Sumatra). Continued protection, combined with consolidating small, fragmented populations into larger ones, and intensifying captive breeding efforts, are the best hope for the species’ survival.