Francis, C. D. | bioRxiv Science

bioRxiv2021

Light and noise pollution impacts specialist wildlife species disproportionately

Global expansion of lighting and noise pollution alters how animals receive and interpret environmental cues. Yet we lack a cross-taxon understanding of how animal traits influence species vulnerability to this growing phenomenon. This knowledge is needed to improve the design and implementation of policies that mitigate or reduce sensory pollutants. We present results from an expert knowledge survey that quantified the relative influence of several ecological, anatomical, and physiological traits on the vulnerability of terrestrial vertebrates to elevated levels of anthropogenic lighting and noise. Our findings, based on 280 responses, highlight the increasing recognition among experts that sensory pollutants are important to consider in management and conservation decisions. Participant responses show mounting threats to species with narrow niches; especially habitat specialists, nocturnal species, and those with the greatest ability to differentiate environmental visual and auditory cues. Our results call attention to the threat specialist species face and provide a generalizable understanding of which species require additional considerations when developing conservation policies and mitigation strategies in a world altered by expanding sensory pollutant footprints. We provide a step-by-step example for translating these results to on-the-ground conservation planning using two species as case studies.

ecology↗

bioRxiv2020

Light pollution affects West Nile virus exposure risk across Florida.

Emerging infectious diseases (EIDs), including zoonotic arboviruses, present a global health threat. Multiple components of human land use change have been linked to arboviral emergence, but one pervasive factor that has received comparatively little attention is light pollution. Although often considered a component of built environments, artificial light at night (ALAN) outpaces the growth and spatial extent of urbanization, and thus affects areas where human population density and anthropogenic land changes are modest. West Nile virus (WNV) emergence has been described as peri-urban, but recent research suggests that its relative ubiquity in human-altered environments might actually be due to ALAN. Indeed, we found previously that experimental ALAN exposure enhanced avian competence to transmit WNV to mosquitoes. In the present study, we asked whether such organismal effects manifest ecologically by determining whether WNV exposure among sentinel chickens in Florida is related to local ALAN conditions. We found strong support for a nonlinear relationship between ALAN and WNV exposure in chickens with peak WNV risk occurring at low ALAN levels. Importantly, effects of ALAN on WNV exposure were stronger than other aspects of urbanization; only ambient temperature in the month prior to sampling had a comparable effect to ALAN. These results represent the first field evidence that ALAN might affect infectious disease exposure risk. We advocate for further research on how ALAN influences zoonotic risk, as well as efforts to study alternative nighttime lighting methods to reduce such risk. Significance StatementLight pollution associated with human development is a globally pervasive and rapidly expanding anthropogenic stressor; but despite documented effects on host immune functions and vector behaviors, how it affects infectious disease risk is unknown. Using data from the Florida Department of Health arbovirus surveillance program, we show that light pollution is a stronger predictor of variation in West Nile virus (WNV) exposure risk than many other previously implicated anthropogenic and natural environmental variables. Light pollution effects are nonlinear, so risk is highest in areas with dim light pollution. Our results highlight a new way that light pollution might affect human and wildlife health.

ecology↗