Impact of light pollution spectra and intensity on the development and mortality of tiger mosquito ( Aedes albopictus ) larvae

Light pollution is a global urban stressor that can impact the behavior, physiology and fitness of many species, including disease vectors such as the tiger mosquito (Aedes albopictus). Experimental and observational studies in diverse arthropods have shown that artificial light at night (ALAN) can either slow development or accelerate it at the cost of higher mortality, suggesting that immature life stages may be vulnerable to light pollution. This study investigated how varying intensities of artificial light pollution - using both high-pressure sodium (HPS) and light-emitting diode (LED) lamps - affect the developmental rates of immature Ae. albopictus mosquitoes under semi-natural field conditions. During a controlled field experiment, newly hatched Ae. albopictus larvae were exposed to five different light intensity levels (10, 30, 60, 100 and 200 lx) under HPS and LED illumination alongside a control group without artificial light exposure. We measured time to pupation and emergence and mortality in both male and female mosquitoes to assess the biological impacts of varying light type and intensity. Our findings indicated no significant differences in average time to pupation or emergence across the different combinations of light type and intensity or control groups. However, greater variation was observed within certain light type and intensity combinations, suggesting potential nuances in ecological impacts not reflected in group averages. Mortality was consistently low across all groups, indicating that light pollution does not significantly impair larval survival in Ae. albopictus. These results suggest that under typical urban lighting conditions, Ae. albopictus development and immature survival remain robust.