Scavenging bird population decline kills 500,000 people

Once upon a time, the vulture was a numerous and ubiquitous bird in India.

Scavenging birds circle over vast landfills in search of cattle carcasses. Sometimes they are sucked into jet engines during takeoff from airports, alerting pilots.

But more than two decades ago, vultures in India began dying due to a drug used to treat sick cattle.

By the mid-1990s, the population of 50 million vultures had plummeted to near zero due to the effects of diclofenac, a cheap, nonsteroidal cattle painkiller that is fatal to vultures. Birds that feed on livestock carcasses treated with the drug develop kidney failure and die.

According to the latest reports, declines have slowed in some areas since veterinary use of diclofenac was banned in 2006, but at least three species have suffered long-term losses of 91-98%. status of birds in india Report.

According to a new peer-reviewed study, that’s not all. The study, published in the journal Nature, said the unintentional killing of these heavy scavenging birds allowed the spread of deadly bacteria and infections, killing around half a million people each year within five years. American Economic Association Magazine.

“Vultures are considered nature’s health servers because they play an important role in clearing our environment of dead animals that contain bacteria and pathogens—without them, disease would spread,” said study co-author, University of Assistant Professor Eyal Frank said.

“Understanding the role condors play in human health emphasizes the importance of protecting wildlife, not just cute animals. They all have work to do in our ecosystems that impacts our lives.

Mr. Frank and his co-author Anant Sudarshan compared human mortality in areas of India where vultures thrived with those in areas where vulture numbers were historically low, both before the vulture collapse Or later. They also examined sales of rabies vaccines, feral dog populations and levels of the pathogen in water supplies.

They found that after sales of anti-inflammatory drugs increased and vulture populations plummeted, human mortality increased by more than 4 percent in areas where vultures once thrived.

The researchers also found that the impact was greatest in urban areas with higher livestock populations, where carcass dumping is common.

The authors estimate that the loss of vultures killed around 100,000 people each year between 2000 and 2005, costing more than $69 billion (£53 billion) annually in mortalities or economic costs associated with premature deaths.

These deaths are due to the spread of diseases and bacteria that condors would otherwise scavenge from the environment.

For example, without vultures, stray dog ​​populations would increase, bringing rabies to humans.

Rabies vaccine sales increased during this period but are still insufficient. Unlike vultures, dogs cannot effectively clean decaying remains, allowing bacteria and pathogens to spread into drinking water through runoff and poor disposal practices. Fecal bacteria in the water more than doubled.

“The collapse of India’s vultures provides a particularly stark example of how the loss of a species can cause irreversible and unpredictable losses for humans,” said Sudarshan, associate professor at the University of Warwick – author of the study.

“In this case, new chemicals are the culprit, but other human activities—habitat loss, wildlife trade, and now climate change—have effects on animals, which in turn affects us. Learn these Costs and identifying target resources and regulations are important to conserve especially these key species.

Among India’s vulture species, the white-rumped vulture, Indian vulture and red-headed vulture have suffered the most significant long-term declines since the early 2000s, with population declines of 98%, 95% and 91% respectively. Egyptian vultures and migrating gryphons also suffered significant, but less catastrophic, declines.

India’s 2019 livestock census records show that the number of livestock exceeds 500 million, ranking first in the world. Vultures are efficient scavengers and have long been used by farmers to quickly remove livestock carcasses. Researchers say the decline in vulture numbers in India is the fastest recorded for any bird species and the largest since the passenger pigeon became extinct in the United States.

India’s remaining vulture populations are now concentrated around protected areas, where their diet consists more of dead wildlife rather than potentially contaminated livestock, according to the State of India’s Birds report. These continued declines indicate “the ongoing threat that condors face, which is particularly concerning given the negative impact condor declines have on human well-being.”

Experts warn that veterinary drugs still pose a significant threat to vultures. The problem is exacerbated by the dwindling supply of carcasses due to increased burials and competition from wild dogs. Quarrying and mining can destroy the nesting habitat of some bald eagle species.

Will the vultures come back? While there are some promising signs, it’s hard to say. Last year, 20 vultures were rescued after being bred in captivity and fitted with satellite tags. freed From a tiger reserve in West Bengal. More than 300 vultures have been recorded in the area recent surveys in southern India. But more action is needed.

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