Ocean map shows ‘nowhere is safe’ from human impact

The first comprehensive mapping of ocean wilderness revealed that no part of the ocean is untouched by humans, and only 13 percent could be classified as “wilderness.”

“Nowhere is safe,” said James Watson of the University of Queensland, an author on the study, in a video abstract for the report.

The exhaustive analysis of human impacts in all global marine ecosystems, published Thursday in Current Biology, categorized and mapped all the ways humans have changed the ocean, such as fishing, shipping and pollution.

The study scored each marine area according to the intensity, number and cumulative effect of human impact, building a map of the ocean and each geographic location’s status. To be classified as “wilderness,” the study defined the area as “mostly free of human disturbance.”

The cumulative stresses on the ocean can be compared in some ways to human health. “If you’ve got a low-grade fever and a knife wound on your arm and a broken leg, and you start adding these things up, each one is pretty bad, but together you’re in really bad shape. You need to hurry to the doctor. And that’s the same idea as what we’re talking about going on in the ocean,” said Ben Halpern, an author on the study and a marine biology professor at the University of California at Santa Barbara.

“To me it is depressing,” said Kendall Jones, lead author and a conservation planning specialist at the Wildlife Conservation Society. “Often you have a picture in your head of these wild places where people don’t really go, and actually that’s not the case. We go really everywhere now. There is not much of the ocean that remains as it once was.”

Coastal areas are the most disturbed by humans, and they’re also the most productive, Halpern said. For example, coral reefs and mangroves are near many cities, provide food and protection from wave damage, and are crowded with underwater life.