It can be difficult to feel sorry for a creature that lives by eating the dead. But vultures fill an important ecological niche, and removing them from the landscape can cause a cascade of changes with devastating consequences, as India has learned in recent years.
Vultures started disappearing from India during the 1990s. The cause, scientists later learned, was the painkiller, diclofenac. The drug is used to treat cattle in India (and elsewhere), but it’s toxic to vultures. When cattle die, the vultures eat the carcasses, get sick and also die. Vultures in India are disappearing faster than the dodo.
You might think that without the vultures to eat the carcasses of the dead, the bodies would just decay. But instead they’ve become a food source for rats and, worse, packs of feral dogs. Feral dogs are a growing problem in India, where they have attacked and killed children, and spread rabies and distemper, threatening a host of other species.
Now Africa could be facing the same problem, and hopes that vultures could be saved through the creation of protected areas have been dashed by a study in PLOS One that found that the birds roam farther than anyone suspected.
“We found that young vultures travel much further than we ever imagined to find food, sometimes moving more than 220 kilometers a day. Individuals moved through up to five countries over a period of 200 days, emphasizing the need for conservation collaboration among countries to protect this species,” study co-author Stephen Willis of Durham University in England said in a press release.
The reason vultures fly so far is that there’s just not enough food for them in the protected areas. Vultures prefer to eat animals that have died naturally, rather than compete with lions and other predators for their kills. The best place for a vulture to find a meal, then, is a pasture far from other carnivores. Sadly, though, the vultures don’t know that those pastures can contain some of the most deadly foods. And until people stop treating their cattle with the problem painkiller, the vulture populations will continue to decline.
Image Credit: Dr. Stephen Willis/Durham University