THE IMPACT OF LIGHT POLLUTION ON NOCTURNAL POLLINATORS AND PLANT REPRODUCTIVE SUCCESS

Abstract

Artificial night light (ALAN) is increasingly gaining popularity as a normal anthropogenic pollution to the environment with terrible consequences on the environment and the nocturnal animals particularly.  This paper examines the impact of the light pollution on pollinators in the night and how this impacts the success of plants reproduction. To do this it employs a mixed-methods experimental design which incorporates field observations, spectral light profiling and quantification of reproductive output at various locations with varying amounts of light.  It is found that there is a strong negative correlation between pollinator activity under light exposure and the visitation rate declined by up to 45 per cent in high-light conditions particularly among the moth species.  The plants at these locations produced over 30 per cent fewer seeds and fruits compared to those plants in lowlight control sites.  Pie charts, scatter plots, and compound visualizations revealed that negative outcomes were not only of a lower number of pollinators, but the nature of species and the manner of their behavior changed as well.  The analysis of multivariate regression revealed that the light intensity of artificial sources was a serious parameter causing negative impacts on the reproductive output of plants.  Spectral preference testing also indicated that moths have a stronger attraction of short wavelength (blue-rich) light making disruption of pollinators far more serious.  The findings demonstrate the ecological impact of unregulated nighttime illumination and instruct an immediate incorporation of dark-sky concepts, lighting curfew and spectral filtering in the city and peri-urban development to mitigate the pace of biodiversity loss.  The current research contributes to the accumulation of the existing knowledge about light pollution which is a significant conservation issue that needs to be addressed within policies that refer to biodiversity, ecosystem services and sustainable development.  The research does not only demonstrate the tenuous nature of night time ecological interactions, but it also provides valuable insight as to how the pollination services which are beneficial to wild and domesticated plant systems can be preserved.