New research published in Ecosystem Services shows vultures mitigate tens of millions of metric tons of CO2 each year, Scientific American has reported. These birds have a vital role in the ecosystem: they feed on carcasses, keeping the nutrients cycling and preventing pathogens from spreading. But beyond that – the new study found – they have an important role in mitigating greenhouse gas emissions.
Each kilogram of a decaying animal body releases approximately 0.86 kilograms of CO2 or equivalent emissions, and an individual vulture eats 0.2 to one kilogram of carcass daily. Thus, collectively, vultures help avoid tens of millions of metric tons of CО2 globally each year, the study said.
The estimate shows that there are 134 million to 140 million vultures across the globe. They help mitigate emissions mostly in the Americas, according to the study led by Pablo Plaza, a biologist at the National University of Comahue in Argentina. The Black, Turkey, and Yellow-headed vultures found only on those continents account for 96% of the vulture-related mitigation. This is equal to 12 million metric tons of carbon dioxide, or as much as 2.6 million cars.
“The decline in vulture populations in many regions of the world, such as Africa and Asia, has produced a concomitant loss of the ecosystem services vultures produce,” Plaza said.
This is a worrying trend, especially since vultures can play an important role in times of climate disasters.
“Without vultures, we have carcasses decomposing at a slower rate, which can cause a series of problematic issues,” said Carolina Baruzzi, a postdoctoral researcher at the University of Florida. Such issues include both increased emissions and disease. Baruzzi’s research showed a striking difference between ecosystems with and without vultures. Ïn two weeks, [carcasses] were usually gone,” if vultures were around, she said. “Where we didn’t have vultures, they stayed there for more than a month and a half or two months.”
Vultures alone are not a major solution to the climate crisis. However, together with other factors, they can make a difference.
“I think the bigger piece here is this idea of a portfolio approach to emissions reduction,” said U.S. Forest Service scientist Grant Domke. “Everything needs to be on the table, and the more we understand about the contributions of plants and animals as part of the economy-wide picture, the better.”