Unintended consequences

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I meant to write about this before, but @celticeagle and her post about cats just reminded me – thanks! A couple of decades ago India had a large population of vultures, and they did an important, but under-appreciated job of clearing up dead animals, especially cattle (which, due to religious practices, are just left to decay when they die). Unfortunately in the 1990s, the patent was lifted on the non-steroidal anti-inflammatory drug diclofenac (also sold as Voltaren), which became cheap and readily available. Consequently farmers gave it to their cattle willy-nilly and when the cattle died and vultures ate the corpses, they died in their droves – it turns out that diclofenac has highly-toxic effects on the kidneys of birds. Vultures were originally so common and ubiquitous that no-one gave them much thought. In fact in some cases they were regarded as a bad omen due to their association with death. But then suddenly they disappeared. The populations of vultures dropped by 96 to 98%, just like that. It took years for researchers to identify what was causing the mysterious deaths, and meanwhile of course the drug was still being used and the vultures were still dying. And because there were no vultures to consume dead cattle and water buffalo, the rotting corpses attracted feral dogs, their population boomed – and as a result it is estimated that an extra half a million people died, partly from rabies when they were bitten by one of the vastly-increased dog population, and partly from other diseases caused by bacteria or toxins leaching from dead animals and contaminating water sources. It turns out that vultures can not only strip a carcase completely in just a few hours, but also have digestive systems that are able to neutralise all these pathogenic agents in a way that other scavengers simply cannot. All life is indeed interlinked in ways we cannot foresee. If you are interested in more detail on this story there is a longer account here: All rights reserved. © Text copyright Fleur 2024. Image from Pixabay.