When the Black-footed Ferret Conservation Center and the City of Fort Collins reintroduced the once-thought-extinct black-footed ferret to the high-plains prairie of Soapstone Natural Area in September 2014, all involved knew it would be a difficult task.
Sixty-two black-footed ferrets have been released in the past two years, according to Daylan Figgs, natural areas senior environmental planner. But only eight or 10 of them currently survive, according to John Hughes, wildlife biologist at the center.
The ferret depends on prairie dogs for food, and colonies of prairie dogs are susceptible to sylvatic plague, as are their ferret predators. (Sylvatic plague is the same flea-transmitted bacterium that wiped out 25 percent of Europe’s population in the 14th century). Hughes hopes additional distribution of oral plague-vaccine baits later this year will protect the prairie dog and ferret populations from the disease and help them to expand. But if that doesn’t work, more exotic tools may soon be used to help restore ferrets and other endangered species to their niches in the living world.
In the February issue of the North Forty News (https://northfortynews.com/crisprcas9-the-geneticists-word-processor/), I discussed the potential power of a new gene-editing tool called CRISPR/Cas9. Swiped from the genetic tool kit of bacteria, this RNA/protein combination allows geneticists to snip out and paste in segments of genetic code with great accuracy in a fraction of the time it used to take. When biologists do this editing in the germ cells of organisms — their eggs and sperm — the changes become permanent and can be passed from generation to generation. CRISPR/Cas9 technology figures strongly in potential plans to help ferret populations in two ways: protect them from plague and increase their genetic diversity so that they will become more resistant and adaptable when facing other threats in their environment.
The first way to help is rather straightforward, though not necessarily easy. Vaccination gives plague immunity to ferrets (and prairie dogs) by inducing them to produce antibodies that fight any future invasions by plague bacteria. If biologists can pinpoint stretches of DNA code for these antibodies, they can duplicate these segments and edit them into the DNA of ferret germ cells to produce resistance in future generations. Kevin Esvelt, an assistant professor at the MIT Media Lab, who helped develop some of the CRISPR technology, proposed this idea. A similar application of the process could help eradicate Lyme disease in humans, which is caused by bacteria transmitted by ticks.
The second way to help has a more science-fiction feel and involves an organization that wants us to transform the way we think about time, nature and the living world: Revive and Restore, a division of the Long Now Foundation. On their website (reviverestore.org) they describe their mission “to enhance biodiversity through the genetic rescue of endangered and extinct species.” They specifically list black-footed ferrets as a rescue candidate. Julie Lyke, deputy recovery coordinator at the Black-footed Ferret Conservation Center, says they have had discussions with the group, but no formal proposals have been made.
All the black-footed ferrets alive today are descended from just seven individuals that have survived episodes of canine distemper and plague since 1981, when a ranch dog named Shep helped discover a relic population of black-footed ferrets near Meeteese, Wyo. (https://northfortynews.com/the-black-footed-ferret-flagship-species-for-the-prairie-ecosystem/) This small founder population makes for low genetic diversity and limits the animals’ response to disease and other problems.
Revive and Restore points out that the DNA of an older, more diverse population exists in the remains of ferrets from 30 years ago that now are stored in the San Diego Frozen Zoo (http://institute.sandiegozoo.org/resources/frozen-zoo%C2%AE). They propose using that DNA to increase the genetic diversity of the existing black-footed ferret population, whose family pedigree is known in exquisite detail because of the work done at the BFF Conservation Center. In practice, knowing just how to enrich a population’s genetic diversity and to what extent becomes a difficult project and one subject to some debate.
Revive and Restore is described as a “nonprofit project within a 501(c)(3) public charity, The Long Now Foundation, which ‘fosters long-term responsibility.’” (http://longnow.org) The foundation proposes that as a society and a civilization we think too much in the short term — a trend that “might be coming from the acceleration of technology, the short-horizon perspective of market-driven economics, the next-election perspectives of democracies, or the distractions of personal multi-tasking.” To counter that trend — to help change the way people think about long-term human goals — the foundation is now building a clock in the Sierra Diablo range of West Texas, near the town of Van Horn, that will tick once a year, bong once a century, and be precise to an accuracy of one day in 20,000 years.
The idea is to create a monument and a library of information that, in the short term, would provide a project and a destination forcing people to think about our legacy as a species, with the hope that we would collectively change the scope of our visions and aspirations — aspirations like restoring species whose contribution to the living world has been lost to a large extent because of short-sighted actions we took in the past.
Restoring black-footed ferrets to help reestablish the health of prairies that once dominated 25 percent of North America thus becomes one part of much larger projects that we are free to conceive — if we can successfully raise our eyes from our portable devices long enough to get a better view of the future in which we want our great-great-great grandchildren to live.