Terrestrial vertebrates faunal assessment in Catubig watershed (Philippines)

Villanueva (Catubig Watershed Management Planning) conducted an inventory of terrestrial vertebrates, namely, amphibians, reptiles, birds, and mammals in the Catubig Watershed from 2002 to 2003. The Catubig Watershed lies north of the Samar Island Nature Park. The total land area is 87,382 ha. It is considered valuable due to the presence of patches of old growth forests mixed with residuals, mostly forests over limestones. It has noticeably high mammal diversity. The Catubig Watershed consists of several dissecting rivers and creeks, feeding the large Catubig River. The headwaters of the watershed lie in the upper streams of these tributaries,which drain the Catubig Watershed, recognized as critical areas for protection. Multi-sampling methods was used to ensure that all aspects of observations were addressed and gaps or biases were avoided. Data collected from the transect counts, nettings, and trapping results were analyzed quantitatively using measurable computations of basic ecological parameters- diversity and abundance.Findings of the study revealed the following: the faunal assessment registered a total of 167 species of terrestrial vertebrates, 13 amphibians, 22 reptiles, 32 mammals,and 100 bird species. Of the 13 amphibian species observed in the Catubig Watershed, 9 were considered as Philippine endemics. Of the 22 reptilian species, only 13 were Philippine endemics. One reptilian species, recently described as Lycodon ferroni, was recorded in the area and considered to be island endemic and regional endemic of high conservation importance. Two threatened reptilian species, the Philippine sailfin lizard and Philippine crocodile, included in the 1994 International Union for Conservation Network (IUCN) red data list,were also noted. Richness of bird species was observed in Catubig Watershed with a total of 100 species, which included 45 species (1 of which was the East Visayan endemic), 12 greater Mindanao endemic species, and 6 migratory birds. Four species of mammals listed in the IUCN red list of globally threatened mammals were recorded, namely rufous horseshoe bat (Rhinolophus rufus), golden-crowned flying fox (Acerodon jubatus),Philippine warty pig (Sus philippinensis), and the Philippine brown deer (Cervus marianus). Also noted in the watershed, was the high density of endangered and endemic fruit bats. Some of these species were considered as island endemic and regional endemic of high conservation importance,and included in the 1994 IUCN red data list and may require regulation. The strict implementation of laws concerning the protection of forest habitats and threatened species is one of the major issues that need to be addressed. Considering the high level of threats in the area,a system of regulation on wildlife trade needs to be addressed in close cooperation with the LGUs and the local DENR.