Seasonality of terrestrial insect families in a neotropical mixed forest environment

Insects are central to ecosystem functioning through pollination, seed dispersal, decomposition, and pest regulation, yet global declines threaten these services. This study examines seasonal dynamics of insect communities and functional roles in a Neotropical mixed forest in Guyana, addressing the deficiency of data on tropical seasonal variation. Species richness showed little difference between wet (97 species, 39 families, 9 orders) and dry (104 species, 43 families, 10 orders) seasons, but abundance varied markedly. Contrary to expectations of higher diversity during the wet season, results indicate peak diversity and abundance occur immediately following rains, at the onset of the dry season. Functional-group analyses revealed seasonal shifts in ecological roles: predator and parasitoid proportions fluctuated relative to decomposers and nutrient cyclers, while pollinator representation remained stable across seasons. These findings highlight that seasonality drives compositional and functional changes in insect assemblages without uniformly altering richness. The dependence of insect populations on climatic variables underscores the importance of resource windows for reproduction and survival. By linking species-level diversity with ecosystem roles across seasonal contexts, this study establishes a baseline for monitoring insect declines in tropical forests and informs conservation strategies aimed at safeguarding critical ecosystem services under changing environmental conditions.