Because the ecoregion covers only elevations above 1,000 metres (3,300 ft), it exists in seven discontinuous patches surrounded by lowland rainforest.

Biodiversity is high, both because of the isolation of separate mountain ranges that have led to species variation within the island, and because of the altitude zonation.

Because most of the surrounding lowland forest has been cleared for human use, the montane regions have become an important refuge for rare and endemic species.

[4] Animal species vary widely in the ecoregion, as unconnected mountain ranges developed different habitats.

Mammals of conservation interest in the region include the Philippine warty pig Sus philippensis, the endemic Mindanao moonrat (Podogymnura truei), and the endangered Mindanao shrew (Crocidura grandis), and the endangered Giant golden-crowned flying fox (Acerodon jubatus).