A new report released today concludes that both the Preble’s meadow jumping mouse (Zapus hudsonius preblei) and its northern sibling, the Bear Lodge meadow jumping mouse (Zapus hudsonius campestris), need the protection of the Endangered Species Act. The report is a critique of petitions to delist the Preble’s mouse submitted by the state of Wyoming and Coloradans for Water Conservation and Development, a developers’ lobbying group. The report demonstrates that both species face a growing risk of extinction from continued habitat degradation and loss.

“Everyone can see that open space and healthy streams on the Front Range are getting hammered,” said Erin Robertson, staff biologist for Center for Native Ecosystems. “It’s easy to understand why the Preble’s meadow jumping mouse would also be in trouble.”

One point of controversy has been whether the Preble’s meadow jumping mouse is a distinct subspecies. Recent preliminary research funded largely by the state of Wyoming concluded that the Preble’s is, in fact, distinct from the widely distributed western jumping mouse (Zapus princeps). The same research suggests that Preble’s may be genetically similar to the Bear Lodge meadow jumping mouse, found in parts of Wyoming, South Dakota, and Montana. However, as today’s report shows, the best available science indicates that both Preble’s and Bear Lodge have restricted ranges and are at risk of extinction.

Conservationists also sharply criticized the preliminary genetic research. Rob Roy Ramey II, the lead researcher, is among those leading the high profile campaign to remove protection for the Preble’s mouse. However, his research failed to answer numerous critical questions and has not been published in a peer-reviewed scientific journal. In fact, Ramey’s preliminary report was criticized by many expert commentators. Concerns included problems with his scientific methods and unsupported conclusions about the conservation status of the Preble’s mouse.

“The Denver Museum of Nature and Science’s researcher is politicizing what is supposed to be an objective scientific review,” observed Robertson. “Rather than allow the scientific process to run its course, they are doing everything possible to hijack the science.”

Several Colorado legislators have jumped on the delisting bandwagon. Senator Wayne Allard issued a statement calling for immediate delisting and Congressman Tom Tancredo introduced a bill that would both delist the Preble’s and prohibit any future Endangered Species Act protection for the mouse.

“For all their bluster about good science, Congressman Tancredo, Senator Allard, and other opponents of the Endangered Species Act are the first to subvert the science when the conclusions don’t go their way,” said Mike Harris, staff attorney with Earthjustice.

The conservation groups that produced today’s report support credible genetic research and, if warranted, a taxonomic revision, but a careful review of the best available science shows that both Preble’s and Bear Lodge require protection regardless of the outcome of current taxonomic research. Habitat for both species is severely reduced and habitat loss to new homes, highway expansions, and other development continues at a rapid rate.

Although years of surveys and research have produced extensive information about the distribution and abundance of the Preble’s mouse that is not yet available for the Bear Lodge mouse, all indications are that the latter, too, is imperiled. The Bear Lodge meadow jumping mouse occupies the same type of habitat and is suffering from significant habitat degradation and loss due to overgrazing, mining, logging, road construction, and sprawl. The nearly unanimous scientific opinion is that the Bear Lodge mouse is at risk of extinction. This assessment is supported by biologists with several scientific bodies tracking the status of at-risk species — the South Dakota Natural Heritage Program, the Wyoming Natural Diversity Database, and the Montana Natural Heritage Program. The Bear Lodge meadow jumping mouse is also listed as “facing a high risk of extinction” by the International Union for the Conservation of Nature, the leading international scientific body monitoring species declines and extinction.

“Any way you slice it, both the Preble’s meadow jumping mouse and the Bear Lodge meadow jumping mouse need protection,” concluded Jeff Kessler, conservation director of Biodiversity Conservation Alliance. “If you lose the habitat you lose the species, and that seems to be exactly what is taking place.”

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