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Plague Kills Many Prairie Dogs and Black-Footed Ferrets in Grasslands Near Badlands National Park


Sylvetic plague not only kills black-tailed prairie dogs like this one, but also the black-footed ferrets that prey on them. Photo by Asiir via Wikipedia.

There is a huge prairie dog town in the Conata Basin, a 20-mile long portion of the Buffalo Gap National Grassland that lies just south of Badlands National Park in southwestern South Dakota. Perhaps not surprisingly, the Conata Basin has proven to be the most successful of the nation’s 17 [url=
black-footed ferret[/url] reintroduction sites.

Last May, sylvatic plague began to spread like wildfire through the Conata Basin. By August the deadly disease had spread to some 9,700 acres of the prairie, killing nearly all of the prairie dogs as well as about 100 of the 290 ferrets living in the 25,000-acre ferret management area.

This plague variant affects only wild animals, so it is dubbed sylvatic.

Spread by fleas and highly infectious, plague poses a dreadful threat to the ferrets. The mortality rate for non-vaccinated ferrets is virtually 100 percent. Because the plague kills prairie dogs, it also depletes the principal food source for surviving ferrets.

Plague has not yet been detected in Badlands National Park, and this encourages scientists to believe that a vigorous program that combines insecticide spraying and vaccination might spare the remaining black-footed ferrets in the park as well as the Conata Basin.

The hot, dry weather of summer slowed the spread of the disease in the basin, giving biologists precious time to spray and vaccinate before cooler, wetter weather arrives. A crew of four has been traveling the prairie in ATVs, spraying flea-killing insecticide dust into prairie dog burrows. They’ve treated over 7,000 acres so far in the Conata Basin and hope to do another 4,000 by fall.
Another crew, which operates at night, traps ferrets and vaccinates them. More than 60 ferrets have been vaccinated so far (15 of them twice, which is the recommended dosage).

We’ll know soon enough whether the spray-and-vaccinate campaign produces the desired protection in the Conata Basin and Badlands National Park. Sylvatic plague also remains a credible threat to the ferrets at Wind Cave National Park and other reintroduction sites in the region.


What makes this a biologically significant issue today is that for over 80 years, the prairie dog has been viewed as the enemy of domestic cattle in the West, and this was based on a notion that the prairie dog would compete with domestic cattle for available forage in a fixed (fenced) area. Because of this idea, prairie dogs have been and are today poisoned on publicly and privately owned grass/ranchlands. While a plague outbreak in this or that geographic region may have historically brought the ecosystem into "balance", as Mr. Janiskee suggests, the present day fact is that 80+ years of prairie dog genocide has brought populations down to approx. 2% of their historic range, which leaves the remaining animals in even greater peril when plague does enter an area. And because the Conata Basin and Badlands are the last best relatively large, contiguous shortgrass prairie ecosystem on our continent, this is/was the best place to reintroduce the black-footed ferret after it was literally brought back from the brink of extinction.
So, when plague threatens the prairie dogs and ferrets in the Conata Basin, Badlands, Pine Ridge, or anywhere else in the region, this means that the recent progress made in bolstering numbers and habitat for these species could be lost, and that very significant human efforts will be necessary to prevent at least one species, the black footed ferret, from vanishing from the earth.

wat is actually killing them is the hunters

I see that these comments are a year old, but I thought it right to make a clarification. And while I actually am an environmental scientist working on their Phd, I don't see that as any reason to be rude or to use language that the average person can't understand.

"Sylvatic plague" essentially is just a phrase scientists use to refer to the version of a plague found in wild animals. Pretty much all mentions of plague refer to disease caused by one specific bacteria, Yersinia pestis. This is the exact same bacteria that caused the bubonic plagues you heard about in history classes. The general consensus is that it originated in Asia and then traveled over to Europe and eventually here to North America via travel in fleas on rodents like rats that moved with humans.

The point being, the "sylvatic plague" referred to in this article is certainly not endemic to the prairies of North America. Endemic implies not only native origin, but also that something is found only in that specific place, which in this case is false on both counts.

As far as the human measures taken to fight this issue go, I would agree that the implications are very tricky to determine accurately. While I don't think the mass application of pesticides is a sustainable solution, scientists must constantly weigh benefits and detriments in their efforts to undo the damages of the past. We can only hope that whoever is making these decisions is doing so in an informed and cautious way.

Hope that helped!

i dont understand what the plagueis what did it affect on these black footed ferrets i am a 7th grade student and want understand about this
i am writing a essay on a endangered animal of my choosing i just of happen to choose the black footed ferret but this is the one thing i dont seem
to understand please e mail me at

what is being done to try to protect it?

Nope, missed the sarcasm completely due mainly to multiple references in prior threads pertaining to the same culprit as the basis for all the world's ills, along with the same self-righteous fool of an ex-VP being touted as the "hero" of the planet. Global warming advocates consistently point to carbon dioxide as the sole evil, which is by far not accurate, and also quote the Goremeister chapter and verse without any qualification or background on the matter, just parroting his position as though the research was their own. The planet is cyclical, like it or not, and unfortunately the "how, why and when" behind the process of it's timing to shift magnetic poles, alter orbital paths or axis orientation along with multiple other factors are not currently within the comprehension of mankind. Alas, it becomes a sensitive arena within which to open a conversation.

I offer my sincere apologies to any offended contributors. But I don't recant my position.

Actually the extended allergy season has nothing to do with goldenrod. The pollen of goldenrod is too large to be carried by the wind and cause allergies. The real culprit is likely ragweed.


For sure, I took your sarcasm hook-line-and-sinker. ;-)

The reason I did, of course, is:

  • Going by Anonymous, I have no idea who's talking, and...
  • ... I read identical (but earnest!) language every day!

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