Vultures which used to be very common in Indian countryside some years ago are rarely seen nowadays. This is attributed to

Answer: (b) a drug used by cattle owners for treating their diseased cattle

Diclofenac, a cheap painkiller given to sick cattle, stays in the carcass. Vultures that eat it suffer kidney failure (visceral gout) and die within days.

The idea

Three Gyps vultures (white-rumped, Indian long-billed and slender-billed) crashed by over 95% between the early 1990s and the mid-2000s.

Sick cattle are given diclofenac → The animal dies with the drug in its body → Vultures eat the carcass → Their kidneys fail → Vultures die within days → Carcasses rot, stray dogs multiply, rabies risk rises

Why the others are wrong

(a) Invasive species were not the driver. The tall trees and cliffs vultures nest on were still there.

(c) Food was never short, since India had plenty of livestock carcasses. The food itself was poisoned.

(d) Scientists first suspected a disease, but a 2004 study proved it was diclofenac poisoning. It was a drug, not an infection.

The trap

Option (d) is the natural guess, because a sudden crash looks like an epidemic. It was chemistry, not disease.

Also know

India banned veterinary diclofenac in 2006; meloxicam is the safe substitute. In 2023 it also banned aceclofenac and ketoprofen for animal use. There is a Vulture Action Plan 2020–25, and a conservation breeding centre at Pinjore (Haryana).