Wild pigs produce as much CO2 as 1.1 million cars, study finds
Two of the biggest targets in the push to lower the world’s CO2 emissions are motoring and agriculture. The two industries have a surprising amount of parallels and overlap, and this has been further underlined by a new study by a network of international researchers for Global Change Biology.
The study aimed to figure out how much CO2 was created by the world’s population of feral pigs, based on a series of models based on data from around the globe. It found that wild pigs produce 4.9 million metric tons of carbon dioxide annually, which roughly equates to the same amount of CO2 produced by 1.1 million cars.
Wild pigs primarily do their damage when uprooting soil, the study found. This is something that they do while finding food. The process exposes microbes in the soil to oxygen, which in turn prompts the microbes to reproduce exponentially, simultaneously causing CO2 to form.
“When we think of climate change, we tend to think of the classic fossil fuel problem. This is one of the additional threats to carbon, and to climate change potentially, that hasn’t really been explored in any global sense,” Dr Christopher O’Bryan of the University of Queensland told The Guardian.
“Any form of land-use change can have an effect on carbon emissions from the soil. The same thing happens when you put a tractor through a field or you deforest land.
“If all we care about is agriculture, then the cost and the benefits of managing pigs will be different than if all we cared about was carbon emissions, than if all we cared about was biodiversity. [...] At the end of the day, feral pigs are a human problem. We’ve spread them around the world. This is another human-mediated climate impact.”
While 1.1 million cars’ worth of CO2 might not sound too significant, given that there’s around 1.5 billion cars on the planet in total. But it’s worth noting that the study named Oceanic countries like Australia and New Zealand as being the most impacted by carbon emissions caused by wild pigs.
Out of the 36,000 square kilometres that the study claims wild pigs are uprooting annually globally, 22,000km is in Oceania. This is the equivalent of 643,000 extra cars on the road across the continent.
“Areas that are peat bogs or black soils … especially ones that have a lot of moisture, they’re a sink for carbon,” Nicholas Patton, a PhD student at the University of Canterbury, told the Guardian. “When pigs get in there and root around, they have a lot more potential for that carbon to be released [than from other soils].”