Some animal species, like these gray gibbons, are being phased out due to insufficient numbers for breeding.
(Listen to Joel talk about the “phasing out” of species.)
It’s a gray, cloudy day at the Miller Park Zoo in Bloomington, Illinois. It’s early, with no cars in the parking lot. They won’t open for another hour or so. Even then they’ll have few visitors. The place is as quiet as a church at midnight. And though you’d never know it, they’re keeping quite a sad secret here.
When any animal in the world zoo population slips below 50 individuals, tough choices—life and death choices—have to be made. Can we get more of the species from the wild to bolster the genetics going forward? If so, is this a showy enough species that the public will pay to come and see it?
For three species in this building, the answer is no.
Take the gray gibbon (pictured below). There are two here, a brother and sister, gray fur balls that go unnoticed on your way to see the Sumatran tiger. But it’s the gibbons visitors should really be looking at, while they can.
“Only 28 remain in the world’s zoos, so they’re being phased out,” said Jay Tetzloff, the zoo’s superintendent. In a world with few of their species left in the wild to bolster the captive population, this means the species is going to be let go to extinction. “We can’t get them from the wild anymore, so there’s no breeding program at all because genetically we can’t sustainably breed them into the future. When the current captives die, that’s it.”
Gray gibbons (Hylobates muelleri) at the Miller Park Zoo in Bloomington, Illinois.
Red-eyed tree frog (Agalychnis callidryas) at the Miller Park Zoo in Bloomington, Illinois.
Red ruffed lemurs (Varecia variegata rubra) at the Miller Park Zoo in Bloomington, Illinois.
Sumatran tiger (Panthera tigris sumatrae) at the Miller Park Zoo in Bloomington, Illinois.
Keeper Erik Heinonen acquaints the Miller Park Zoo’s bobcat (Lynx rufus) with my seamless white backdrop.
Snow leopard (Uncia uncia) at the Miller Park Zoo in Bloomington, Illinois.
Red-fronted macaw (Ara rubrogenys) at the Miller Park Zoo in Bloomington, Illinois.
Gold-handed tamarin (Saguinus midas) at the Miller Park Zoo in Bloomington, Illinois.
Thai bamboo rat snake (Oreocryptophis porphyracea coxi) at the Miller Park Zoo in Bloomington, Illinois.
There are exceptions to the “50 Rule.” The Sumatran rhino is down to just nine captives, but it’s a much bigger, higher-profile animal, so breeding attempts will continue. People know and love rhinos, tigers, gorillas, and pandas enough to keep zoo gate attendance up wherever they’re found. Not so for a gibbon the color of a spent campfire, easily overlooked against concrete walls as it sleeps the day away.
The gibbon is not alone. Across the hall in a glass-fronted room with a jungle painted on the walls is the red-handed tamarin. It’s being let go for much the same reason. There is only so much space and funding, and there are three far showier species of small primates that zoos will concentrate on instead. And that rusty-spotted genet down by the exit? Why, he’s the only one known in captivity. The future of his kind is the least secure of all.
Of course I write here about the most dramatic examples I know to illustrate the extinction crisis and all that’s at stake. We’re just starting to go downhill though. There is still time to save most of the world’s living treasures, but first we have to know they even exist, and then care about what happens next.
So the big question is this: Do you care enough to do something?
Support your local zoo. Reduce, reuse, recycle. Insulate your house and drive a smaller car. Vote with your wallet or purse by spending your money in an eco-friendly way. Vote in every election you can, and make your voice heard. What you do matters. I promise.
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