HAMID Abang A Forest Department of Sarawak, 研究員
ITIOKA Takao Faculty of Agriculture, Nagoya University, 農学部, 助手 (40252283)
HASHIMOTO Yoshiaki Himeji Institute of Technology, 自然環境科学研究所, 講師 (50254454)
ITINO Takao Faculty of Agriculture, Kagawa University, 農学部, 助教授 (20176291)
|Budget Amount *help
¥4,200,000 (Direct Cost: ¥4,200,000)
Fiscal Year 1996: ¥2,000,000 (Direct Cost: ¥2,000,000)
Fiscal Year 1995: ¥2,200,000 (Direct Cost: ¥2,200,000)
Ant-plant mutualism and diel behavior of some dominant ant speceis were studied in a lowland rain forest in the Lambir National park, Sarawak, Malaysia. We recognized more than 30 ant species attending hemipteran (mainly homopteran) insects, and also about 30 hemipteran species intensively attended by ants. Approximately 85% of phytophagous insects found on forest floor trees and shrub were hemipterans attended by ants.
Among the 5 parties, i. e., 11 Macaranga species (ant plants) associated Crematogaster species (specialist ants) at least 3 coccoid species reared by ants, 2 Narathuru species (leafeating butterflies) and 3 cecidomyiid species (gall midges) there were rather strict species-specific relations in Lambir. The relation was compared between 3 different forests : Lambir, Kubah, and Gunung Mulu.
Preventing the access of associated ants to ceitain leaves of some Macaranga species caused a significant increase in the amount of damage by leaf-eating insects. On the Macaranga trees receiving insufficient sunlight the colonies of Cremato-gaster ants tended to decline, ant some of them died owing to the increased damage by walking sticks and planthoppers. In coccoids that were reared by ants, the morthality rate was high during earlier stages of larva, and approached zero during adulthood. This strongly suggested that ants ustilize young coccoids as their food.
The diel habits was observed for army ants (genus Aenictus) that are supposed to have a serious effect on the ant community. The movement of marching and food items were studied with 2 commonity found species, A.laeviceps and A.gracilis. Each party stayd in one place for about half day, then moved toanother site after exhausted almost all ant colonies there. For A.laeviceps 22 ant species in 8 genera, and for A.gracilis 5 species in 2 genera, respectively, were observed to be transported by army ant workers as food. We have yet few information about the role of victim ant species playd on the plants.