And although state records focus on the hefty mammals that endanger drivers—deer, elk, moose, bears, and the like—they’re mum on smaller critters, such as snakes, frogs, and birds, all of which have likely thrived during COVID-19. “We’re measuring the large animals, but I suspect it’s true for all animals, including insects,” Shilling said. (In Texas, millions of monarch butterflies succumb to grilles and windshields during their migrations to Mexico.) Add up all those less conspicuous casualties and extrapolate globally, and it’s hardly a stretch to say that hundreds of millions, perhaps billions, of wild animals will ultimately be spared because of the pandemic.
Nor is it just hyper-abundant animals, such as squirrels and raccoons, that are finding succor during the Anthropause. In California, the poster species for highways’ harms is the mountain lion, several populations of which may soon be protected under the state’s Endangered Species Act. Shilling found that mountain lion roadkill plummeted 58 percent after the shutdown. “When you’re talking about such small populations, you get even one cat taken out by roadkill, and that can spell doom,” Beth Pratt, the California director of the National Wildlife Federation, told me. The Anthropause isn’t merely protecting individual lives, it turns out—in some places, it may be safeguarding the persistence of entire species.
Although all available evidence suggests that net roadkill rates have dropped, it’s conceivable that, on some roads, deaths have actually ticked upward. For many species, cars—loud, terrifying, alien—deter animals from crossing altogether, leading one early road ecologist to describe traffic as a “moving fence.” In Oregon, researchers found that mule-deer collisions peaked at around 8,000 cars per day; beyond that threshold, the ungulates appeared to abandon their migration routes entirely rather than attempt to cross. As traffic has declined during COVID-19, then, animals may feel more comfortable venturing onto certain highways, at their peril—leading ultimately to localized roadkill hot spots. And even if it wasn’t more abundant this spring, roadkill might, in some states, simply be more visible, as agencies tasked with cleaning up carcasses divert resources to the coronavirus response.
How long will the benefits of the roadkill reprieve linger? In early March, Shilling and his colleagues found, Americans drove 103 billion total miles; by mid-April, shutdowns had reduced our collective travel to 29 billion miles, an astonishing 71 percent cut. As travel bans have eased, though, traffic has crept up again, to about half its pre-pandemic levels in California and Maine. Although cities like Milan, London, and New York have seized the opportunity to install new bike lanes and de-emphasize cars, many urban areas have registered more gridlock, as commuters spurn public transit for the socially distant cocoons of their personal vehicles.