It took just a few days of lockdown for baby rabbits to dare to cross once-bustling roads in Christchurch, New Zealand, and less than a week for a puma to descend from the Andes Mountains into Santiago, one of South America’s busiest capitals. In Barcelona, wild boar, a familiar sight for citizens on the city’s outskirts, have made their way into Diagonal Avenue, an eight-lane thoroughfare.
It’s surprising and strange, yes, but also meaningful. Research suggests that ecosystems can rebound with speed once human intervention subsides. A review published last week determined that damaged ecosystems and wildlife can be rebuilt if the right conditions are achieved. Marine ecosystems in particular can substantially recover by 2050, according to the study, led by Carlos Duarte at the Red Sea Research Center in Saudi Arabia.
Of course, a deadly pandemic that brings about a sudden economic collapse is no way to sustainably restore threatened ecosystems. Yet it’s a clear reminder of how quickly the wild world responds when humans take a step back.
Scientists have tracked this pattern for decades. The number of humpback whales migrating from Antarctica to eastern Australia has been increasing each year, from a few hundred animals in 1968, when commercial whaling was banned, to more than 40,000 today. In 1880 only 20 breeding northern elephant seals had survived decades of hunting, and today there are more than 200,000.
Hunting bans, habitat restoration, and the reduction of water pollution are all linked to the recovery of marine species. The continuation of these practices—and, most of all, working to mitigate the effects of climate change—would contribute to oceans recovering significantly by 2050, the researchers said.
It’s more difficult for land ecosystems to bounce back because both the scale of extinction and the scale of human presence are so large there, said Duarte, a marine science professor. But these differences don’t mean the return of wildlife to deserted city streets isn’t significant, he said: “I believe our own confinement, and the release of wildlife from confinement, should bring some empathy between humans and wildlife moving forward.”