By Carrie Flood
Lots of people have a bit of an “ew” reaction to vultures. Maybe it’s the bald head, or it could be all those BBC nature specials with footage of vultures’ necks deep in carcasses…whatever it is, vultures don’t engender tender feelings in most humans. You don’t find too many kids who want to cuddle up with one, and social media isn’t exactly flooded with adorable clips of vultures running in grassy fields or playing with chew toys. But is it possible that vultures get a bad rap? Could knowing a little more about the important role vultures play in the environment help people appreciate (if not want to cuddle), these feathered giants?
A very popular show used to run on the Discovery Channel, called “Dirty Jobs,” and by the end of the show viewers had an appreciation for the people who did some of the nastiest jobs on the planet, and an understanding of the importance of those jobs. Maybe you don’t want to clean sewer lines yourself, but we understand what would happen if no one was doing that job, right? A large part of my job is cleaning up poop. It isn’t pretty, or particularly fun, but if no one cleaned up poop at the zoo, things would go south pretty quick. No one wants to picnic at a zoo without poop scoopers; trust me.
Well vultures are like that. They clean up the environment. Dead animals, if left alone, breed bacteria that can cause disease in humans. When it rains, that bacteria is washed into rivers or streams and contaminates the water. Vultures have a digestive system that breaks down all those nasty germs so they can’t cause disease. The bald head of the vulture can be wiped clean easily by the bird, and anything left over bakes off in the sun because it’s not covered by feathers. (Shout out to the bald peeps out there!)
In areas where vultures are disappearing, diseases are breaking out in humans. The decline of vultures in India is thought to be the cause of a rabies outbreak that killed almost 50,000 people! Because vultures weren’t consuming the carcasses of cows and local wildlife, feral dogs had this new source of food and their numbers skyrocketed. Rabies spread quickly among the dogs, which lived in close contact with people, allowing the disease to move between them. And it’s not just rabies – vultures keep all kinds of diseases – including anthrax – from spreading. We are just now beginning to appreciate the value of vultures as they experience drastic population declines and we see the effects of a world without them.
California condors are the second largest vulture species after their Andean cousins. They were once widespread in the western half of the US and into Canada and Mexico, out there cleaning up the elk and bison carcasses, keeping diseases out of the ecosystem and whatnot. When European settlers started moving west, condor numbers began to decline. Condors were shot outright, perhaps because they made such large targets or maybe because they were associated with death. Settlers purposely poisoned carcasses to kill off “undesirable” animals like wolves, coyotes and mountain lions but condors also fed on the poisoned meat and died. Condors reproduce with breathtaking slowness, so it didn’t take long before the population was endangered. It got so bad that by 1982 there were a total of 22 California condors alive in the world.
Enter San Diego Zoo Global…. It was decided that the only hope for the survival of the condors was to bring them into human care. San Diego Zoo Safari Park was selected to spearhead the effort. They built giant aviaries and put some of the most determined biologists to work breeding condors. (All behind the scenes – none of this was done where the public would see it. Often zoos do their most important work in quiet environments behind the scenes, urgently working to save the most endangered animals out of the spotlight.) It wasn’t easy but with the cooperation of organizations including the US Fish and Wildlife Service, Los Angeles Zoo, Oregon Zoo, Santa Barbara Zoo, The Peregrine Fund and others, the captive population stabilized. Condors mate for life. They lay one egg at a time and will spend a whole year raising a chick before laying again. If a pair loses an egg, the female will often lay a replacement egg. Savvy keepers began pulling the first egg and hatching it in an incubator, so the female condors would lay a second egg; effectively doubling production of condors. Hand-reared chicks were fed with condor puppets to reduce the risk of the young birds imprinting on humans, and eventually placed with an older mentor bird, so they grew up knowing how to be a condor.
The first birds were released back into the wild in 1992, and now the total population of condors is around 500, with almost 200 of them living free in Arizona, Utah, California and Mexico. While this is great progress, these birds aren’t out of the woods yet.
One of their most readily available food sources is gut piles left by hunters field dressing their kills. (Again, the important job of cleaning that mess up!) Traditionally, many hunters use lead ammunition, which fragments on impact and is often part of those gut piles. Lead is a soft metal, which means the condors can digest it – it gets into their bloodstream and causes lead poisoning. Hunters aware of the problem do a great job of packing out gut piles or switching to copper-based bullets, which don’t make the birds sick, but many hunters aren’t aware of the problem, or prefer the ammunition they’ve been using for years. Lead poisoning is the leading cause of death in wild condors. We still have a long way to go there with raising public awareness and encouraging the use of non-lead ammunition.
Finally, condors are ridiculously easily habituated. Naturally curious and surprisingly intelligent, they occasionally show up where people are and figure out that if they sit there and look cute long enough, some well-meaning human will feed them. People food is a terrible diet for the birds, but the main problem is that hungry condors soon start harassing innocent people for food. It’s one thing when your labradoodle begs at the table, but when a 20lb bald bird with a ten-foot wingspan and a razor-sharp bill raids your picnic lunch, it can be unsettling. And condors aren’t great at taking no for an answer – they can just get more and more insistent until someone gets hurt.
The two condors at the Phoenix Zoo are good examples of this. Both were previously wild, both became habituated to people. Repeated attempts to discourage the behavior and relocate the birds were unsuccessful. In order to keep both people and the condors safe, it was decided the birds had to be taken into managed care. Since they aren’t part of the breeding population, housing them at Phoenix Zoo frees up valuable space for breeding birds at other facilities.
Next time you’re at the zoo, head over to the Arizona trail and say hi to our boys. Measure your wingspan against theirs. Check out that colorful bald head and those eyes, which are likely also checking you out. Can you spot the two different kinds of African vultures hanging out in the Savanna with the giraffes? Both species are endangered, and research done here is helping to conserve them in the wild, but that’s another story for another day….
Shout out to all vultures, out there cleaning up after everyone and keeping diseases out of the ecosystem. Maybe they aren’t so “ew” after all.