Assessing the relationship between anthropogenic nightlight, noise, and avian contributions to ecosystem services

Abstract

Anthropogenic sensory pollutants, especially anthropogenic nightlight and noise (ANLN), are well-known agents of habitat degradation for many bird species. Studies show that ANLN can also induce physiological stress, affect habitat selection, and reduce the reproductive success of birds, but the large-scale effects of ANLN on the ecosystem services birds provide have not been examined. I categorized 60 bird species based on the services they provide and used mixed effects models to predict their probability of occurrence within the contiguous United States during their breeding season. I then spatially modeled species’ occurrence rates based on the partial dependence effects of each pollutant separately and summed the rates by service category to produce predicted service maps. Of the 60 species, night light and noise showed significant effects on occurrence for 8% (n=5) and 22% (n=13) of species, respectively. Nightlight was negatively correlated to seed dispersal and invertebrate pest control, and noise positively or negatively correlated with these services, dependent on species. Though many species’ occurrence was not drastically affected by ANLN levels, over certain thresholds, many occurrence rates dropped to zero (n=40 and n=53 species, for nightlight and noise, respectively). This largely explains the >50% predicted reduction of urban area services; however, why some areas, such as the Mojave Desert, saw similar reductions due to noise is unclear. Given ANLN's lack of consistent effects in >75% of models, these results suggest ANLN may not inevitably decrease all avian services. Further research is needed to examine the nuances of ecosystem service and avian species' resilience across the ANLN gradient.