The park comprises an area of 130,000 ha. It contains a variety of lowland and coastal habitats, including one of the largest freshwater swamp forests in Sumatra. The relatively open character of the forest coupled with a few trails makes it a rewarding site, where you can observe several unusual species of bird and animal. Mammals of note include Elephant, Agile Gibbon, Siamang, Leopard Cat, Tapir, Sumatran Rhino and Sumatran Tiger . Leeches are quite prevalent on the loop and forest trails but almost absent from the main access track.
Tigers are present in the area, and the staff all carry bear alarms.
A friend of mine visited a few months previously and came across a Tiger on the loop trail behind the guesthouse. The animal was found to be guarding a kill very close to the trail, so be careful. The area is easily reached in about 7 hours from Jakarta, so you could add a trip here to a Java and Bali itinerary. The accommodation is basic, but fine and very cheap at around Rp 10,000 per night. References The book to take is Birds of Borneo, Sumatra, Java and Bali by MacKinnon and Phillipps.