Bird Species Diversity in Various Land Covers in Oil Palm Plantation of PT GSIP, Central Kalimantan

The diversity of birds is strongly influenced by the type of land cover. Oil palm plantations have been confirmed to change the type of land cover from what were once secondary forest, shrubs, and/or open land into palm trees with various age classes. Therefore, it is very interesting to examine the variations of bird species diversity under the different types of land cover. This research was conducted using a transect method (length 1 km and width 100 m) over various types of land cover: young, medium, and old-aged oil palm trees, secondary forest, shrubs, and high conservation value (HCV) area. Observation took place in the morning and evening with five replications. Types of data recorded at the time of observation consisted of bird species and number of individuals. The data obtained were analysed using the Margalef index and Sorensen's similarity index. The total number of bird species found in all land cover types amounted to 37 species from 22 families. The HCV area had the highest species number (21) and highest species diversity index (4.55), while the lowest diversity index was found in the old-aged oil palm plantation (2.72). Old-aged and medium-aged oil palms showed similar bird species compositions (similarity index of 0.89).