The Eefect of Herbivory on the Abundance of Shrubs in the St. Paul Subterranean River National Park, Puerto Princesa City, Palawan, Philippines

Abstract

The purpose of this study is to determine the effects of herbivory on the abundance of shrubs in the rainforests of the St. Paul Subterranean River National Park in Puerto Princessa City, Palawan, Philippines. The point-center quarter method was used for sampling and the relative abundance of the four shrubs encountered was determined. Fifty leaf samples were taken from each species and the percent herbivory was calculated. The first species was identified as Premna subscendens with a relative abundance of 74 % and an average percent herbivory value of 9.03 %. The second species was identified as Morus alba L. with a relative abundance of 12 % and an average percent herbivory value of 16.52 %. The third species was identified as Strophantus cumingii with the least relative abundance value at 5 %, and the highest mean percent herbivory value at 20.8 %. The fourth species was only identified as Pagioga, with a relative abundance of 9 % and a mean percent herbivory value of 16.15 %. The results indicate an indirect relationship between the magnitude of herbivory for a species of shrub and its abundance.