The Bukit Barisan mountain range that runs down the full length of Sumatra reach altitudes of over 3,000 meters above sea level (m asl), with the highest peaks being Gunung Kerinci in West Sumatra (3,800 m asl) and Gunung Leuser (3,404 m asl) in Aceh. Sumatran orangutan habitat is primarily in lowland areas. The highest…