Thesis (BS Biology) -- University of the Philippines Mindanao, 2005

A survey of birds was done in the forest edge and forest interior of Mount Mahuson and Mt. Sinaka, Arakan, Cotabato Province. Mist nets and point counts recorded a total of 102 species belonging to 35 minutes, with 52 Philippine endemics and 14 Mindanao endemics. Some birds can survive in a wide range of habitat and have conspicuous behavior, consequently, they were found in all of the sites (250. Conversely, some birds have reticent behavior and limited ranges and were found in a single site only (39). Edge effects influence species richness by either promoting the proliferation of generalist feeders in Mount Mahuson, with 54 species in its edge and only 52 species in its interior, or by inhibiting the survival of interior specialists in Mount Sinaka with 75 species in its interior and only 47 species in its edge. Using Jaccard?s coefficient, high community similarity (55.88% and 46.99%) was observed between edges and interiors within the same type of sites found in different mountains illustrating minimal edge effects. Physical assessment of the area showed that human disturbances threaten avian diversity indicating the need for immediate conservation measures.