Endangered black-footed ferrets, like children, aren't exactly
lining up to be stuck with a vaccine, but in an effort to help
control an extensive outbreak of plague in South Dakota, some of
the ferrets are getting dosed with a vaccine given by
biologists. This is the first time the vaccine has been used
during a major plague epizootic—an animal version of a human
epidemic. Sylvatic plague is an infectious bacterial disease
usually transmitted from animal to animal by fleas. This exotic
disease is usually deadly for black-footed ferrets and their
primary prey, prairie dogs. Black-footed ferrets are one of the
rarest mammals in North America. In mid-May, the Centers for
Disease Control confirmed sylvatic plague in black-tailed
prairie dog colonies in the Conata Basin area of Buffalo Gap
National Grasslands in southwestern South Dakota. As of late
June, about 9,000 acres of prairie dog habitat — including
colonies occupied by vulnerable black-footed ferrets — have been
infected by the disease, according to U.S.