Marinduque is an island of 172,700 ha off the southwestern coast of Luzon. It is hilly and reaches a maximum altitude of 1,153 m. Two small blocks of old growth forest are shown on recent forest cover maps around the highest peaks in the center and south of the island. Most of the forest remaining on the island is likely to be lowland in type, with some montane forest above c.1,000 m. This IBA includes the small Torrijos Watershed Reserve, which has an area of 105 ha.
Several of the threatened and restricted-range birds of the Luzon Endemic Bird Area have been recorded on Marinduque, but the ornithological coverage there appears to have been rather sparse and more survey work may locate more of these species. There is a population of the threatened Green Racquet-tail on the island, but it is believed to be small. Six subspecies of birds are endemic to Marinduque, Amethyst Brown-dove Phapitreron amethystina imeldae, Blackish Cuckoo-shrike (see above), White-browed Shama Copsychus luzoniensis shemleyi, Mangrove Blue Flycatcher Cyornis rufigastra marinduquensis, Purple-throated Sunbird Nectarinia sperata marinduquensis and Mountain White-eye Zosterops montanus gilli.
Non-bird biodiversity: Threatened endemic mammals recorded on Marinduque include the Philippine Pygmy Fruit Bat Haplonycteris fischeri and the Southern Luzon Giant Cloud Rat Phloeomys cumingi, which was last recorded in 1890 but may still be present in the area. The Philippine Warty Pig Sus philippensis, which used to be common is now extinct in this IBA. Other endemic mammals like Philippine Pygmy Roundleaf Bat Hipposideros pygmaeus, Philippine Nectar Bat Eonycteris robusta and Large Rufous Horseshoe Bat Rhinolophus rufus are also found in this IBA. Endemic herpetofauna so far recorded in this IBA are Giant Philippine Frog Rana magna macrocephala and Truncate-toed Chorus Frog Kaloula conjuncta. The waters around Marinduque are also known to support threatened animals, such as Olive Ridley Turtle Lepidochelys olivacea, Green Turtle Chelonia mydas, Hawksbill Turtle Eretmochelys imbricata and Spinner Dolphin Stenella longirostris.
BirdLife International (2020) Important Bird Areas factsheet: Central Marinduque. Downloaded from http://www.birdlife.org on 26/10/2020.