Protected areas are a tool used by environmentalists to protect resources and biodiversity. By officially cordoning off parks, preserves, and wildlife sanctuaries, natural habitats and species can flourish.
But a new report in the journal Science found that a third of those protected areas are under intense pressure from human encroachment.
Globally, there are 200,000 protected areas that range in size, but six million square kilometers of that faces environmental pressure from agriculture, encroaching human settlement, roads, light pollution, rail, and infrastructure development on waterways.
Researchers looked at the “human footprint,” a global map showing these pressures first published in 2016, and compared where these footprints treaded over protected areas. One of the study's authors, James Watson, is from the Wildlife Conservation Society, a conservation group that strives to protect wildlife. He says threats to critical species and natural resources are compromised by this growing human encroachment.
“There's a good chance the biodiversity crisis will be exacerbated,” said Watson in a press release. He's referring to what scientists are increasingly saying is a dangerous decrease in the world's biodiversity. When biodiversity decreases, it has cascading effects.
For example, in the U.S., fewer past protections for predators like bobcats were linked to the increase in lyme disease. Researchers found that, as predator populations decline, deer populations increase, providing more transient hosts for the blood-sucking ticks that carry lyme and other diseases.
It's a crisis that scientists like renowned ecologist E.O. Wilson have tried to address by advocating for more fully protected areas that allow biodiversity to thrive. Wilson ambitiously called for protecting half the Earth last October.
The study's authors say their findings are a wake-up call, not only to rethink how biodiversity is protected, but also to revise plans to meet standards set by the Convention on Biological Diversity. The 1992 treaty mandates that its 196 signing parties must take steps toward ensuring biological diversity by preserving resources.
Whether the world can actually meet those goals is now in question.
Elizabeth O’Donoghue is the director of infrastructure and land use at the Nature Conservancy (TNC). Given the rate of global population growth, she wasn't surprised by the study's findings.
At TNC, she and her colleagues developed a resource called “Green Print” that allows communities or developers to see potential environmental issues in the San Francisco area. The region is one of the fastest growing in the U.S., so much so that it's even led to a housing crisis. While it wasn't identified in the paper, the region has struggled to balance biodiversity and human encroachment.
“Right now the Bay Area has seven million people. It's growing to 9 million. And it's a biodiversity hotspot,” says O’Donoghue. TNC's tool allows information to be spread, but she notes it's just a start. Truly ensuring biodiversity longterm requires popular and political support, she says.
So what are some of the real impacts of not protecting resources?
“Plants and animals that have made the Bay Area so attractive would really go downhill,” says O’Donoghue. “Wide-ranging species would not have those large rangelands to traverse. The natural ability of nature to absorb rainwater to provide groundwater recharge. Drinking water and air quality would be impacted.”
Despite the gloomy outlook painted by the study, it's findings weren't all negative.
In regions that are strictly protected, the team found fewer instances of human encroachment, meaning stricter enforcement could help regions meet their biodiversity goals.
The study did not look at how climate change or conflict impacted protected areas, which scientists warn can have big impacts longer term.