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Monday, August 31, 2015

Zoo History: Prairie Phoenix

There are times when the fight to save endangered species seems like a losing game.  The list of defeats is a long one, and each win seems temporary at best, a pyric victory that comes at another species' expense at worst.  Here and there, however, are little glimmers of hope.  There are three species in particular - three US natives - that I tout the stories of frequently, citing them as examples of both why the struggle is worth while and why zoos in particular matter.  One is the California condor; the second is the red wolf (though there seems to be a regrettable amount of backsliding on this one as of late).  The third is an obscure, handsome little weasel that at times seemed more like a ghost than a real, flesh-and-blood animal.

John James Audubon (for whom the Audubon Zoo and Audubon Aquarium of the Americas are named) is best known for his bird paintings.  He also painted other animals, however, and it was in one of these paintings that he introduced western science to a striking, weasel-like mammal, a tawny, bandit-masked little beast portrayed in the act of robbing a bird nest.  That was the scientific world's first introduction to Mustela nigripes, the black-footed ferret, at the time a resident of the seemingly endless prairie dog towns that covered the American West.  It was a new find for Audubon but a familiar face to the Blackfoot, Crow, and other first nations of the plains, many who considered the ferret sacred and used its pelt for ceremonial regalia.

Audubon's painting captured the ferret's likeness well, but it was wrong in one sense - bird eggs don't feature too prominently on the menu of the ferret.  Instead, it feeds almost exclusively on prairie dogs, slipping stealthily down burrows to hunt and kill the ground squirrels.  Unfortunately for the ferret, as much as it loved prairie dogs, settlers hated them, considering them pests fit for eradication.  The prairie dogs themselves were too numerous to drive to extinction, but there numbers were diminished sufficiently that, if you were an animal that ate only them, you were in trouble.  Coupled with introduced diseases, the ferret vanished from the face of the plains.  Soon, Audubon's print was all that left... and some people thought that he must have made the critter up entirely.  Even those who did believe in the ferret thought it must be extinct by the middle of the twentieth century.

Miraculously, a small colony was discovered in South Dakota in 1964.  The ferrets, believed to be the last of their kind, were brought into captivity to start an emergency captive breeding program... and they all died.  By the dawn of the 1980's, the black-footed ferret was believed to be extinct... again.

Second chances in conservation are rare.  Third chances are almost unheard of.  And yet, that is what scientists were offered when a taxidermist in Meeteese, Wyoming, told authorities that he had just been presented with a freshly killed ferret in 1981.  The taxidermist in turn had been given the body by a local rancher, who had himself been given it by his dog, who had killed it one night.  A new population of ferrets was discovered, though it was vanishing quickly beneath the onslaught of distemper and plague.  The decision was made to try captive breeding again, and a final effort was made to save the species.  This time, there was a little more success.

Captive breeding began at a facility in Wyoming.  The partnership expanded to include other government agencies, as well as AZA-member zoos.  Participants included Louisville Zoo, Toronto Zoo, Phoenix Zoo, Omaha's Henry Doorly Zoo, Cheyenne Mountain Zoo, and the Smithsonian Conservation Biology Institute.  The tiny population had be managed carefully to reduce inbreeding, as there were no new founders that could be drawn upon.  Ferrets that were past their reproductive prime were sent to other zoos to serve as display animals, educating members of the public about this endangered but little-known species.  Slowly, the population was built up.

It wasn't simply a matter of keeping ferrets alive in zoos in genetically-healthy numbers.  The challenge was also how to help reestablish the species in the wild.  Disease was a major cause of the ferrets' decline, so immunization was of key importance.  Wild ferrets eat only prairie dogs, so zoo ferrets had to learn to hunt prairie dogs.  Facilities responded by placing prairie dogs in enclosures full of soil and allowing them to burrow, then allowing the ferrets to roam the actual prairie dog burrows, filled with the scent of actual prairie dogs.  Besides finding food, ferrets had to learn to avoid becoming food for larger animals.  At some facilities, a taxidermied-badger was affixed to a remote-controlled car and this "RoboBadger" was used to teach ferrets that badgers were dangerous.

In 1991, the moment of truth came and the first releases occurred in Wymong.  Today, there are 24 reintroduction sites across eight US states and the three countries that formed the historic range of the ferret -  the United States, Canada, and Mexico.  What has been most inspiring about the efforts has been the vast array of partners which have come together to help ferrets return to the wild.  They roam across federal and state land, of course, but private landowners have welcomed ferrets to their property.  Several Indian nations have likewise allowed ferret releases on tribal land.

Today there is a secure captive-breeding population, which is providing surplus ferrets for reintroduction across the west.  Ferrets are also being translocated from site to the site in the wild to protect genetic diversity.  More reintroduction sites are being identified and explored.  In short, the black-footed ferret isn't safe by any stretch of the imagination, but it's a whole lot safer than it was when the only known specimen of the species was a corpse dangling from the jaws of a farmer's dog.

Which is just as well... because I doubt that we'll be getting a fourth chance.

Learn more about the Black-Footed Ferret Recovery Program at

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