Decline in India's vulture population impacted human health, contributing to thousands of deaths: Report

Vultures are scavengers and play a vital role in the circle of life as they provide sanitation services by removing carcasses from the environment. A new study has found that they also serve an important role in protecting human life.

A decline in the vulture population in India led to ecological and socio-economic impacts and it is a known fact that the implications of biodiversity loss on ecosystems and human societies can be extensive. The population of Indian vulture severely declined during the crisis in the 1990s, resulting in the listing of the species as Critically Endangered on the IUCN Red List in 2002.

The new study has revealed that over 500,000 people died between 2000 and 2005 as a result of disease-carrying germs spreading from an excess of dead animals, which was caused due to near-extinction of vultures in India, science.org reported on Monday (Jul 15).

The vultures started dying because of non-steroidal anti-inflammatory medication diclofenac which is extremely poisonous to the birds. When they unintentionally consumed diclofenac-contaminated carcasses, they suffered kidney failure and visceral gout, which can be fatal. The Indian government banned the use of diclofenac in 2006.

The study, which is currently online as a working paper and will be published in an upcoming issue of the American Economic Review, mentions that the monetary damage from the related public health crisis is nearly $70 billion a year.

As quoted by science.org, Atheendar Venkataramani, a health economist at the University of Pennsylvania, said: "This [paper] will be a classic in the field. It's going to generate a lot of new science." Venkataramani was not involved with the study.

Eyal G Frank and Anant Sudarshan have conducted the research. They said that the Indian government required tanneries to use chemicals to dispose of the waste, causing toxic substances to enter waterways used by people.

To understand the impact of the same, vulture habitat maps were superimposed on Indian administrative district maps by the researchers as they examined medical records for over 600 areas while adjusting for hospital count, weather and water quality.

As per the report, human death rates in districts surveyed averaged about 0.9% per 1000 people before 1994, which is a baseline that accounted for whether there were a lot of vultures in a particular district.

However, the report mentioned that areas that were traditionally home to a large number of vultures saw a 4.7% hike in human death rates on average, or roughly 1,04,386 additional deaths per year by the end of 2005. The study also found that death rates in those districts that weren't the typical homes of vultures remained stable at 0.9%.

The study also highlights why the conservation of species in their natural habitat or natural ecosystem is important.

(With inputs from agencies)