Spurious Species

Mice vs. landowners.

In 1998, the U.S. Fish and Wildlife Service listed the Preble's meadow jumping mouse, which inhabits river valleys along the eastern flank of the Rockies, as "threatened" under the Endangered Species Act, leaving many landowners unable to develop their land. More than 31,000 acres of private and public property were effectively locked up.

That might change. Last year Rob Roy Ramey, then-curator of the Denver Museum of Nature and Science, published a study in Animal Conservation concluding, based on genetic and morphological comparisons, that the hapless rodent was no different from other, more common jumping mice. Landowners soon petitioned to have the mouse removed from the endangered species list. "The federal government has effectively shut off tens of millions of dollars of economic development," property-rights activist Kent Holsinger told The Wall Street Journal, "based on saving a species that we now know doesn't even exist."

Biologists at the Fish and Wildlife Service hurriedly conducted another genetic study, which contradicted Ramey's. As a review panel debates the proper classification of the creature, the fate of the mouse—and of the people who own its habitat—is up in the air.