Temporal dynamics and microhabitat-associated variation in Aedes albopictus abundance and oviposition behaviour in a...

Mosquitoes are among the most dangerous insects for human health as vectors of numerous pathogenic arboviruses; among them, Aedes albopictus is one of the most epidemiologically relevant species due to its high vector competence and wide geographic expansion. Understanding its population dynamics and oviposition behaviour in peri‑urban environments is essential for the development of targeted surveillance and control strategies. Adult abundance was monitored in a Mediterranean peri‑urban context using BG-Sentinel traps from June to October 2023, while oviposition activity was assessed via ovitraps. The study evaluated associations with meteorological conditions, vegetation characteristics, ground substrate, and diel timing. A total of 1590 adult mosquitoes were collected, showing a pronounced bimodal seasonal pattern with peaks in August and late September. Adult abundance was positively associated with cumulative rainfall during the two weeks preceding sampling. Microhabitat variables (hedge species, orientation, substrate) had limited associations with oviposition, although grass surfaces and denser vegetation showed slight positive trends. By contrast, oviposition activity was more consistently associated with seasonal progression and diel timing than with the measured microhabitat variables. In particular egg-laying during the crepuscular-dawn period (low-light period, 18:00-11:00 of the following day) was higher than during the diurnal period (11:00-18:00). Temporal patterns at both seasonal and diel scales were more strongly associated with variation in egg abundance than the measured microhabitat variables. These findings indicate that integrated adult-oviposition monitoring can improve the interpretation of population dynamics and may help inform more effective integrated vector management interventions.