Meeting Abstract
Pesticide usage in rice fields has surged since the early 1970’s in the Philippines to help meet the food needs of a rapidly growing population. An increased exposure to pesticides can lead to health problems in humans and compromise various life history traits of organisms in the surrounding environment. Rice fields provide habitat to many amphibian species that may provide pest control services that could lead to reduced pesticide use. We evaluated food consumption of Rhinella marina (invasive species) and Fejervarya vittigera (native species) to determine whether amphibians provide potential to control insect pests in rice fields. Standard transects were conducted on 12 nights. We collected 34 F. vittigera and 63 R. marina and flushed their stomach contents; complete or partially digested insects were collected. All organisms were identified to order and classified as rice pest, non-rice pest, predator, scavenger, or parasitoid. R. marina ate a significantly greater numbers of individual food items compared to F. vittigera, but there was no difference in the total mass of their food items. F. vittigera ate more pest species of rice, R. marina ate more predatory species. Hence the invasive toad may not provide the same level of ecosystem services for pest control as the native F. vittigera since it ate fewer pest items and more rice pest predators. Future research needs to quantify whether actions to increase the density of native frog populations of F. vittigera can moderate high insecticide use in rice fields.
