Abstract:

Species form complex interactive networks within communities, which often experience seasonal species oscillations or species composition shifts. However, the variation that occurs within such networks is poorly understood. Studying seasonal changes of ecological networks may reveal the mechanisms that maintain the stability of a community. In this study, we collected fig wasps from Ficus benjamina during the dry and rainy seasons in Xishuangbanna to understand how fig wasp communities may shift seasonally. We compared fig wasp abundance, species composition, and metrics of coexistence networks (e.g. network diameter, connectance, nestedness, and community temperature) between the rainy season and the dry season. The pollinating wasp, Eupristina koningsbergeri was the most abundant species in both rainy season and dry season. There were more non-pollinating fig wasp species during the dry season (15 fig wasp species) than the rainy season (14 fig wasp species). A higher number of non-pollinating fig wasps can be detrimental to fig-pollinator wasp mutualisms because they reduce both fig seed production and pollinator abundance. Additionally, the dry season experiences higher species connectivity (0.95 in dry season, 0.47 in rainy season), higher network temperature (23.24 in dry season, 2.64 in rainy season) than the rainy season, which indicate more complex inter-specific interactions, and a higher level of disturbance of fig wasp community in the dry season.

Key words: fig-fig wasp, insect community, ecological network, seasonal variation, species interaction