From Gizmodo’s article on the presence of plague out in the Rocky Mountains:
The Rocky Mountain Arsenal National Wildlife Refuge was forced to undergo a temporary closure as a “precautionary measure” last month while it worked to address the issue affecting colonies of black-tailed prairie dogs and endangered black-footed ferrets dependent on them for shelter and food, the U.S. Fish & Wildlife Service said Saturday.
And all I can imagine are prairie dogs offering the ferrets crumpets and tea.