Endangered Species Act Protection for the Preble’s Meadow Jumping Mouse Will Be Reinstated In Wyoming
July 8, 2011: A federal judge in Denver accepted the Service’s proposed course of action to restore Endangered Species Act (ESA) protection for the Preble’s meadow jumping mouse in Wyoming beginning August 6.
We had asked the judge to remand and vacate our 2008 decision to continue to protect the mouse in Colorado but not in Wyoming. That decision was based on the Significant Portion of the Range (SPR) policy at that time that allowed us to apply ESA protections to those portions of a species’ range where we believed it was most threatened instead of all the places where it is found. However, since then we have withdrawn the solicitor’s opinion on which the SPR policy was based, and are in the process of revising our policy. Because we based our 2008 determination on a policy that has been determined to be invalid, we asked the court to vacate that decision.
We have committed to revise our finding on a petition from the State of Wyoming to delist Preble’s populations in Wyoming, and we will publish the results of that review in June 2013. The revised finding will be informed by a new policy on Significant Portion of the Range, which will be developed and finalized in the next year.
In the interim, Preble’s populations in Colorado and Wyoming will be federally protected with a special rule in place to allow rodent control, agricultural operations, landscape maintenance, noxious weed control, ditch maintenance, and other specified activities to occur provided they are conducted in accordance with the requirements of the special rule. We will be working closely with the State of Wyoming and private landowners to minimize the disruption this action through streamlined ESA consultation and by providing feasible avoidance and minimization measures.
The Preble's meadow jumping mouse (Zapus hudonius preblei) (Preble's or PMJM) is a small mammal approximately 9-inches in length with large hind feet adapted for jumping, a long bicolor tail (which accounts for 60% of its length), and a distinct dark stripe down the middle of its back, bordered on either side by gray to orange-brown fur. This largely nocturnal mouse lives primarily in heavily vegetated, shrub dominated riparian (streamside) habitats and immediately adjacent upland habitats along the foothills of southeastern Wyoming south to Colorado Springs along the eastern edge of the Front Range of Colorado. The Preble's mouse enters hibernation in September or October and doesn't emerge until May. Its diet changes seasonally and consists of insects, seeds, fungus, fruit and more.
Once the glaciers receded from the front range of Colorado and the foothills of Wyoming and the climate became drier, the Preble mouse was confined to the riparian systems where moisture was plentiful. The eastern boundary for the Preble's is likely defined by the dry shortgrass prairie, which may present a barrier to eastward expansion. Preble's is one of twelve subspecies of meadow jumping mice found throughout North America.
Typical habitat for Preble's is comprised of well-developed plains riparian vegetation with adjacent, relatively undisturbed grassland communities and a nearby water source. These riparian areas include a relatively dense combination of grasses, forbs, and shrubs. Preble's are know to regularly range outward into adjacent uplands to feed and hibernate. 
The Preble's Meadow Jumping Mouse was found in Colorado in 1899 by Edward A. Preble. Listed in 1995 as a threatened species, the Preble's is long lived for a small mammal, compared to other species of mice and voles that seldom live a full year. Preble's mice captured as adults were still alive two years later. The PMJM has a long list of predators that includes garter snakes, rattlesnakes, bullfrogs, foxes, house cats, long-tailed weasels, hawks, owls and others. The Preble's meadow jumping mouse is believed to have two litters each year with an average size of five young.
The PMJM recently documented distribution includes Adams, Arapahoe, Boulder, Denver, Douglas, El Paso, Elbert, Jefferson, Larimer and Weld counties in Colorado; and Albany, Laramie, Platte Goshen, and Converse counties in Wyoming. The Colorado portion of this area had undergone rapid residential, commercial, and industrial designation that has impacted the PMJM habitat.
On July 10, 2008, the Service removed Endangered Species Act protections for Preble's meadow jumping mouse populations in Wyoming and amended the listing for Preble's to indicate the subspecies remains protected as a threatened species in the Colorado portion of its range.
The Service has determined the best commercial and scientific information available demonstrates that the Preble's meadow jumping mouse is a valid subspecies and should not be removed from the list of threatened and endangered species based on taxonomic revision.
BACKGROUND
On May 13, 1998, the U.S. Fish and Wildlife Service (Service) designated the mouse as threatened in its entire range (63 FR 26517). On June 23, 2003, we designated critical habitat for Preble’s (68 FR 37275). On May 20, 2004, we made permanent a final section 4(d) special rule for the Preble’s that provides exemptions from Section 9 take prohibitions for certain rodent control activities, ongoing agricultural activities, maintenance and replacement of existing landscaping, existing uses of water, certain noxious weed control and ditch maintenance activities (66 FR 28125, 67 FR 61531, 69 FR 29101). Click here for more information on the Special Rule.
On February 2, 2005, we issued a 12-Month Finding on a petition to delist the Preble's and proposed to remove the mouse from the Federal list of threatened and endangered species (70 FR 5404). On February 17, 2006, the Service extended the rule-making process an additional six-months due to substantial disagreement regarding the sufficiency or accuracy of the available data (71 FR 8556; 71 FR 16090).
On November 1, 2007, the Service announced a revised proposal to remove the Preble's populations in Wyoming from the List of Threatened and Endangered Species; and proposing to amend the listing for Preble's to indicate the subspecies remains threatened in the Colorado portion of its range. Additionally, the best commercial and scientific information available demonstrates that the Preble's is a valid subspecies and should not be removed from the List of Threatened and Endangered Species based upon taxonomic revision (73 FR 39790).
More information on PMJM can be found at the Service's ECOS web page or by contacting the Colorado field office at (303) 236-4773.
