"In the past century, humans have become the dominant predator across many systems."
So begins a startling new report about humanity's impact on the planet, published Friday in the journal Science. The study, by researchers at the University of Victoria in Canada, points to the huge impact that human society has had on food webs and ecosystems around the globe and dubs our species an unsustainable "super predator."
For evidence, the team only had to look to the oceans, where humans remove fish at 14 times the rate of marine predators. Humans, the study points out, are "particularly intense" when it comes to hunting, and have used powerful killing technology (trawl nets, guns and mechanized slaughterhouses, for example) to dominate other predators.
"Hunters 'capture' mammals with bullets, and fishes with hooks and nets," author Chris Darimont told reporters, according to the BBC. "They assume minimal risk compared with non-human predators, especially terrestrial carnivores, which are often injured while living what amounts to a dangerous lifestyle."
The research echoes what many scientists have warned for years: If we don't stop overfishing, we may soon run out of animals to catch. Many fish populations have been hunted to the brink of collapse, shark populations have been decimated and less than 8 percent of southern bluefin tuna remain.
The report also notes that it's not just the sheer number of animals that humans kill for food -- some estimates say 56 billion farmed animals are slaughtered annually -- it's the type of animals we take. Humans focus on adult prey, unlike other predators. A full-grown lion, for example, often opts for the smaller, weaker juvenile zebra rather than an adult.
This distinction makes it harder for animal populations to recover as breeding members are removed. "We are dialing back the reproductive capacity of populations," Darimont said.
The paper suggests altering the food we choose to hunt, to focus on smaller, younger prey. But humans are far too good at using more of the planet's resources than we should.
We've already consumed this year's worth of the world's resources, and it's only August.