Vulture decline linked to 100,000 additional human deaths annually

Vultures, often described as "nature’s sanitation service," play a crucial role in removing dead animals that harbour bacteria and pathogens, preventing the spread of disease. 

"Understanding the role vultures play in human health underscores the importance of protecting wildlife, and not just the cute and cuddly. They all have a job to do in our ecosystems that impacts our lives," said study co-author Eyal Frank, an assistant professor at the University of Chicago's Harris School of Public Policy.

The decline in vulture populations has been attributed largely to the veterinary use of diclofenac, which was banned in 2006. Although the decline has slowed in some regions, at least three vulture species have experienced long-term population losses of 91-98%, according to the latest State of India's Birds report.

The new peer-reviewed study, published in the American Economic Association journal, indicates that the decimation of these scavenging birds has allowed deadly bacteria and infections to proliferate, resulting in around half a million deaths over five years. 

"The vulture collapse in India provides a particularly stark example of the type of hard-to-reverse and unpredictable costs to humans that can come from the loss of a species," said Sudarshan, an associate professor at the University of Warwick and co-author of the study.

Specifically in India, a 2019 livestock census recorded over 500 million animals, the highest number in the world. However, researchers note that the decline of vultures in India is the fastest ever recorded for a bird species and the largest since the extinction of the passenger pigeon in the United States. 

Of the vulture species in India, the white-rumped vulture, Indian vulture, and red-headed vulture have experienced the most severe long-term declines since the early 2000s, with populations decreasing by 98%, 95%, and 91%, respectively.