Chasing the Rains: Seasonal Dynamics of Herbivorous and Predatory Insects in Savannahs in Kruger National Park, South Africa

Tropical savannahs experience pronounced seasonality, especially in rainfall and temperature, shaping plant productivity and resource availability. Yet, temporal patterns in insect diversity remain poorly understood. We investigated seasonal variation in species richness and community composition of moths (herbivores) and mantises (predators) across four main landsystems in Kruger National Park, South Africa. Using light traps during early and late wet seasons, we captured 65 593 moths (817 morphospecies) and 3511 mantises (38 morphospecies). Species richness of both groups significantly increased from the early to the late wet season, particularly in the wetter southern landsystems, likely driven by rainfall-enhanced resource availability and habitat complexity. Community composition varied seasonally and among landsystems, with moths primarily influenced by seasonal changes, whereas mantises responded more strongly to landsystem differences. Our results indicate that rainfall-driven seasonal resource variability is a key determinant of insect phenological patterns in tropical savannahs. Predicted shifts in rainfall patterns due to climate change may alter insect emergence timing and trophic interactions, highlighting the importance of incorporating seasonal dynamics into biodiversity conservation and management strategies.