With fewer than 80 individuals remaining, the Sumatran rhino is the most critically endangered large mammal on Earth, requiring extraordinary conservation interventions.
Sumatran rhinos are solitary forest animals requiring large territories and specific fruiting forest resources. Habitat fragmentation isolates individuals who may never encounter another rhino for breeding. Captive breeding attempts have caused welfare concerns including reproductive pathologies in isolated females. The psychological burden of extreme rarity - reflected in population-level loss of social and reproductive opportunities - makes this both a conservation and welfare crisis of the highest magnitude.