A new report highlights the peril the world's vultures are facing and the mayhem that would ensue without the services they provide.
Pity the vultures, the poor things. Is there a bird more maligned? Granted, they don’t have the long elegant legs of waders or the candy-colored charisma of tropical birds – no, they have the hunched shoulders of a leering, hand-rubbing old man and a bald face with which to better insert their heads and necks into the steaming entrails of a carcass. But they are incredibly designed creatures who are an integral part of the ecosystem, and for that alone they are magnificent.
We may have a cultural bias against cackling scavengers, but it’s time to learn to love vultures. They are certainly not without their charms – they form monogamous pairs, they divide labor well and they’re social. The have awesome collective names like "a wake of vulture," or "committee," or "venue." They rarely kill other creatures, and here’s where their value is immeasurable; they subsist entirely on the already-dead meat of other animals, and in doing so, they provide an incredibly quick cleanup of killed animal carcasses. And now a pair of researchers is highlighting that importance, noting that vultures are in distinct danger of disappearing, and that such a loss “would have serious consequences for ecosystems and human populations alike.”
The study comes from the University of Utah and it’s a fascinating illustration of how an ecosystem works – one piece goes astray and everything else begins to go wonky. Consider it a clarion call from researchers, Evan R. Buechley and Cagan H. Sekercioglu, who warn: “We urge immediate action, particularly by regulating lethal dietary toxins, to prevent the extinction of vultures and loss of respective ecosystem services.”
Here is what the problem looks like:
Vultures are the single most threatened group of birds on the planet due to a number of factors, the greatest threat being poisoning from eating poisoned animals.
In North America the problem historically has been with toxic lead bullet bits left over after hunters have field-dressed animals.
In India more than 95 percent of vultures were gone by the early 2000s thanks to diclofenac, a veterinary drug for cattle pain that was highly toxic to vultures who fed on fallen cows.
In sub-Saharan Africa, death comes by way of potent newly affordable poisons used to keep predator pests at bay; also, poachers poison carcasses to keep vultures from divulging locations. "Vultures are taking the hit, indirectly, for a lot of this human-wildlife conflict, as well as the illegal trade in animal parts," Buechley says of the ongoing crisis.
With fewer vultures, a second tier of scavengers emerges. Populations of facultative scavengers, animals that don’t rely on carrion exclusively, can increase dramatically and create an imbalanced food web. "All these facultative scavengers are also predators, and so they also go out and eat other organisms too," Buechley says. "You have this cascading effect."
Vultures can clean a whole carcass within an hour, before decay can set in. Their stomachs kill most of the bacteria or viruses in carrion, acting as an ersatz cleaning filter and removing these toxins from the environment before they can be spread. Buechley notes:
Other facultative scavengers are not so adapted, and could pass along those diseases into human populations, as many are already fixtures in cities. For example, following the decline of vultures, India experienced a strong uptick in feral dogs – by an estimated seven million. The increase in dogs, potentially feeding on disease-ridden carcasses, is thought to have at least partially caused the rabies outbreak that was estimated to have killed 48,000 people from 1992-2006 in India – deaths that may have been avoided if not for the disappearance of vultures.
North America and India have instilled conservation efforts and the picture there isn’t as grim, but Africa is troublesome. The researchers predict that unless something is done there: “Crows, gulls, rats and dogs will boom. And the rabies outbreak in India may just be a prologue, because several sub-Saharan Africa countries already have the highest per-capita rabies infection rates in the world. Rabies is only one of the many potential diseases that vultures had helped regulate.”
Stories of vulture recovery offer plotlines of success, in California the condor population went from 22 in the 1980s to more than 400 now, but the cost of doing so may be more than the developing world can pay.
"It's good news and bad news," Sekercioglu says. "It shows that we can bring back these scavengers. But the bad news is that once we get to these numbers, it costs tens of millions of dollars and decades to bring them back. You don't want to go there. And once you go there, we can afford to save only a few species."
Buechley suggests, "the better solution is to invest in vulture conservation here and now, in order to stem incalculable damage from trophic cascades and increased human disease burden in the developing world."
And with that in mind, who wants to join my vulture fan club?