Earthworm diversity and populations in different habitats of Rajah Sikatuna Protected Landscape, Bohol, Philippines

An earthworm survey was conducted to determine the species composition, diversity, and species richness in the grassland, agricultural areas, and secondary forest habitats of Rajah Sikatuna Protected Landscape (RSPL). Six indigenous morphospecies of earthworms were identified, which are putatively new species. These include one Amynthas species, three Polypheretima species, and two Pheretima species. Also, Pontoscolex corethrurus, an invasive species was found to be the most abundant species of earthworm in grassland and agricultural areas but not in the secondary forest. The diversity index showed a high level in the secondary forest with low species richness. Agricultural and grassland areas showed a low level of diversity. Land use and abiotic factors can be related to the composition of earthworm communities in different habitats. Further studies must be conducted for the conservation and sustainable management of its biodiversity and habitat.