A "vulture apocalypse" kills half a million people

 

The Telegraph in Britain reports that the vulture population in much of India was almost wiped out by the agricultural use of animal medication.  That, in turn, led to a vastly increased human death rate.

The sudden collapse of India’s vulture population has led to more than half a million excess human deaths in the last five years, according to a peer-reviewed study in the American Economic Review.

A flock of vultures can pick a carcass clean in a matter of minutes, purging the environment of harmful bacteria and pathogens that accumulate on the rotting remains of livestock and preventing the spread of deadly diseases.

Even the excrement of some species of vulture can carry cleaning powers, with its high acidity helping to disinfect the ground surrounding the dead animal corpses.

But in the 1990s, vulture populations on the Indian subcontinent plummeted by a staggering 99 per cent – the fastest decline of a bird species in recorded history, according to the latest State of India’s Birds report.

For years, scientists were baffled by the sudden extinction. It was only in 2004 that diclofenac – a cheap painkiller widely used to treat cattle that is deadly to vultures if they ingest it  – was identified as the cause.

. . .

“When these birds disappeared, suddenly there were all these dead carcasses lying around…and were no longer delivering these scavenging services,” Dr Sudarshan told The Telegraph. “That change was quite visible.”

The report estimates that the decline caused a four per cent rise in human deaths in districts where the birds once thrived, resulting in more than $69 billion (£53 billion) per year in mortality damages – the economic costs associated with premature deaths.

After the vultures disappeared, the rotting carcasses of livestock animals oozed diseases and bacteria that polluted waterways and fuelled a rise in feral, and sometimes rabid, dogs.

There's more at the link, including a note that the same painkiller is used in Africa, and a similar drop in the vulture population is taking place there too - albeit at a slower pace.  Nevertheless, its progress is inexorable.

This is, of course, a tragedy for the vulture, and for India's rural population;  but it illustrates yet again how an advance in one field can lead to serious problems in another.  It's the law of unintended consequences at work.  Trouble is, one can only see that in hindsight - usually after it's too late to undo much of the damage.

I can't help wondering what this means for the Towers of Silence in the Zoroastrian religion, which has many followers in and around India.  Devotees expose the bodies of their loved ones in these towers, where vultures and other carrion eaters devour their flesh, leaving only the bones.  Did the sudden drop in the vulture population cause difficulties with this, just at the time when the number of "excess dead" requiring their services abruptly increased because of the birds' decline?

Peter