2025 Volume 34 Issue 1 Pages 1-9
Most insects in temperate regions and tropical regions with distinct dry seasons exhibit seasonal life cycles that are adapted to seasonal climatic conditions. These insects tend to exhibit seasonal fluctuations in abundance at certain stages of their life cycle. Previous studies have shown that most insect species in several taxa display no clear seasonal patterns in their population fluctuations in the Bornean lowland tropical rainforests, where seasonal climatic changes are minimal, and there are no distinct dry seasons. However, the responses of insect populations to aseasonal climatic conditions in the tropical rainforest areas of the Southeast Asian tropics have not been sufficiently studied, and patterns in temporal population trends need to be investigated for a wider range of insect taxa. In this study, we investigated the temporal population trend of 11 abundant cicada species using data of individual numbers of cicada species collected by monthly light-trapping for the four years from 1993 to 1997. The majority of the target cicada species did not show any clear seasonal patterns in their population fluctuations. In contrast, clear seasonal patterns were detected in the population trends of two cicada species, Dundubia vaginata and Purana sp. 2., with the abundance peaking around March and November, respectively.
