Rhinos once roamed many places throughout Eurasia and Africa and were known to early Europeans who depicted them in cave paintings. Long ago they were widespread across Africa's savannas and Asia's tropical forests. But today very few rhinos survive outside national parks and reserves. Two species of rhino in Asia—Javan and Sumatran—are Critically Endangered. A subspecies of the Javan rhino was declared extinct in Vietnam in 2011. A small population of the Javan rhino still clings for survival on the Indonesian island of Java. Successful conservation efforts have helped the third Asian species, the greater one-horned (or Indian) rhino, to increase in number. Their status was changed from Endangered to Vulnerable, but the species is still poached for its horn.