How a Die-Off of Vultures Cost a Country Billions
“Trophic cascade” may sound scientific, but it’s simply “nature’s domino effect.” Everything in nature is interconnected, so if you disrupt one element, a ripple effect begins. Take, for instance, the food chain: bugs eat grass, birds eat bugs, and snakes eat birds. Remove snakes from the equation, and bird populations grow, eating too many bugs. This disrupts the balance, leaving fewer bugs to control grass growth, which then overtakes other plants. Just one change can throw the entire ecosystem off balance.
One real-life example of a trophic cascade happened in India. Several years ago, India’s vulture population began to vanish, causing a dramatic and costly ripple effect across the country. Before the 1990s, vultures thrived in India, numbering in the millions and playing an important role in Hindu culture. Known as nature’s cleanup crew, vultures were essential to maintaining a healthy ecosystem. Anytime animal carcasses were left out, vultures quickly cleaned them up, preventing the spread of disease and keeping communities clean.
However, in the mid-1990s, things took a turn. In India, livestock such as cows and goats are part of everyday life, and when these animals became ill, they were often treated with a drug called Diclofenac. While this anti-inflammatory was effective in easing livestock pain, it proved deadly to vultures. When vultures fed on carcasses of animals treated with Diclofenac, they ingested the drug, which caused kidney failure and death. The vulture population experienced a massive die-off, declining by 96-99% from 1992 to 2003. Three main species were affected: the long-billed vulture, slender-billed vulture, and oriental white-backed vulture.
With vultures disappearing, dead animals were left to decompose. This wasn’t just unsightly; it was hazardous. Rotting carcasses provide an ideal environment for pathogens that cause diseases like tuberculosis and brucellosis. As these diseases spread through water sources and other animals, humans were also at risk. Dogs, another scavenger species, quickly filled the gap left by vultures, leading to an explosion in the feral dog population, estimated to have grown by 5-7 million between the early 90s and early 2000s. Unfortunately, these dogs are a primary vector for rabies in India, causing up to 96% of cases. Rabies is always fatal if untreated, and the increase in dog bites led to tens of thousands of additional human deaths. The cost of rabies treatment and efforts to control the feral dog population created a financial burden of approximately $34 billion annually from 1992 to 2006.
Estimating the total cost of India’s vulture decline is difficult, but experts believe it surpassed $150 billion over 14 years. Fortunately, the situation has started to improve. In 2006, India banned Diclofenac, and livestock owners now use a safer drug called meloxicam. Since the ban, the vulture population has stabilized, and conservationists have implemented breeding programs to encourage growth. Some vulture populations still thrive in remote forests, where agricultural contamination is less common, allowing these resilient birds to fulfill their role in the ecosystem without risk of Diclofenac exposure.
Though challenges remain, India’s vultures have a hopeful future. Conservation efforts and a safer environment could see these iconic birds soaring once again, ready to restore nature’s balance.
