1) There are 5 species of rhinos, two of which are critically endangered. The Javan rhino has fewer than 80 individuals remaining in a single national park in Indonesia. 2) Rhinos have acute senses of smell and hearing but poor eyesight. They live in herds called crashes and communicate using vocalizations and scent marking. 3) Poaching is the main threat faced by rhinos due to demand for their horns in traditional medicine. Conservation efforts aim to protect rhino habitats and populations.