Sumatra has a wide range of plant and animal species but has lost almost 50% of its tropical rainforest in the last 35 years. Many species are now critically endangered, such as the Sumatran ground cuckoo, the Sumatran tiger, the Sumatran elephant, the Sumatran rhinoceros, and the Sumatran orangutan. Deforestation on the island has also resulted in serious seasonal smoke haze over neighbouring countries, such as the 2013 Southeast Asian haze which caused considerable tensions between Indonesia and affected countries Malaysia and Singapore.