Issues: Disease and natural disasters
Small populations + natural calamities = catastrophic consequences
The Indian or greater one-horned rhino, which has almost 60% of its population in Kaziranga National Park in India, suffered a loss of over 30 rhinos during the floods of 1998.
From December 1981 to February 1982, at least five rhinoceros died when a viral infection that first hit water buffaloes in villages surrounding Ujung Kulon park (Indonesia) spread to the population of the Javan rhinoceros. Many Javan rhinos also died in 1935 because of anthrax.