Bako is probably the best place in Sarawak for wildlife experience. The park has been a protected area since 1957, so the animals are less wary of humans.

Taken from:

http://www.forestry.sarawak.gov.my/forweb/ np/np/bako.htm

With its rainforest abundant wildlife, jungle streams, waterfalls, interesting plant life, secluded beaches and trekking trails, Bako offers visitor an excellent introduction to the rainforest of Borneo.

Bako contains an incredible variety of plant species and vegetation types and this is one of the park's great attractions. At Bako it is possible to see almost every type of vegetation found in Borneo. 25 distinct types of vegetation from seven complete eco-system, Beach vegetation, Cliff vegetation, Kerangas or heath Forest, Mangrove Forest, Mixed Dipterocarp Forest, Padang or Grasslands Vegetation and Peat Swamp Forest. It is wasy to explore these eco-system via the jungle trails. The contrasts are so distinct that you do not have to be scientist to notice the differences.