Figure 4
From: Elevated wildlife-vehicle collision rates during the COVID-19 pandemic
Drivers of changes (Δ) in traffic volume across the United States. Changes in traffic volume between July 2018–June 2019 and July 2019–June 2020 across the fifty states and Washington, D.C. were correlated with (A) human population density and (B) local disease burden: traffic volume declined most in densely populated states and in states with either low or high disease burdens. Both (C) the severity of COVID-19 restrictions and (D) baseline traffic volumes were also related to traffic volume: traffic volume decreased most where restrictions were most severe and decreased least in states with high baseline traffic volume. However, COVID-19 restrictions and baseline traffic volume were not significant in all of our top models (Table S4). Response curves were predicted using model 26, which included all four covariates as predictors of changes in traffic volume (Table S4). Blue points correspond to decreases and red to increases, with darker colors signifying greater relative changes.
