In India, the feral dogs can't match the efficiency and speed of vultures when it comes to disposing of carcasses, says Bowden. This means that many carcasses are left to decompose naturally or, in some cases, are incinerated. Carcasses release greenhouse gasses when they decompose, including CO2 and methane. But most of these emissions are prevented if the vultures dispose of them, according to a study released earlier this year by scientists at the National University of Comahue in Argentina. The study estimated that a single vulture consumes between 0.2 and 1kg (7 and 35oz) of decaying carcass meat per day, depending on the species. When it's left to decompose naturally, each kilogram of carcass meat emits about 0.86kg of CO2 equivalent, or CO2e. Using these estimates, the scientists calculated that the 134-140 million vultures worldwide could be preventing tens of millions of tonnes of emissions per year, an amount comparable to the emissions of some countries. "This ecosystem service contributed by vultures to humans and nature cannot easily be replaced by other species, including humans," the study notes. However, due to the absence of vultures, rotting carcasses in India are now often buried, dumped at landfill sites, or thrown in the river, where they risk contaminating the water and result in odour pollution around cities, says Prakash.
Isabelle Gerretsen, ‘Why we should value scavengers’, BBC
