Fleas at the site carried sylvatic plague, a disease that was killing the ferrets and their prairie-dog prey.
Because they had no experience living in the wild, they didn't know to find prairie-dog burrows to live in.
However, in 2008, researchers confirmed the presence of sylvatic plague in prairie-dog
towns within the park, yet another threat to the prairie dogs and so to the thin strand that ties the black-footed ferret to survival.
When spring fishing begins to fall off, prairie-dog
shooting picks up, and when hunting seasons begin to slow down, winter predator hunting takes off.
But the prairie-dog
study shows that, at certain times of the year, healthy adult males can be at risk, too.
In interviews with 20 of 22 exposed persons, 6 (32%) reported recent prairie-dog
bites, 7 (37%) ate or drank without handwashing after contact with prairie dogs, and 13 (67%) handled prairie dogs or cleaned cages barehanded.
Researcher Brian Miller identified 170 vertebrate species sustained by prairie dogs; higher numbers of o birds and mammals live inside prairie-dog
colonies than in adjacent grasslands.
This is why Knowles and other researchers have repeatedly documented cattle and wild ungulates seeking out prairie-dog
For a more macabre look at this sport, see also Thomas McIntyre, Little Dogs on the Prairie; Techniques and Equipment for Prairie-Dog
Shooting, SPOUTS AFIELD, Apr.
From 15 feet (5 m) up in his wooden lookout tower (see photo at right), John can see what's happening in the whole prairie-dog
"Walking into a healthy prairie-dog
town is like walking into a zoo," he says.
Prairie dogs warn their colony of approaching danger with a language of chirps that includes more than 100 "words," according to Northern Arizona University researcher Con Slobodchikoff, who discovered this prairie-dog