1997-06-13_REPORT - M1981302 ‎(16)‎

• Permit No: M1981302
• IBM Index Class Name: Report
• Doc Date: 6/13/1997
• Doc Name: EXHIBIT A 12
• Media Type: D
• Archive: No

CONCLUSIONS AND RECOMMENDATIONS
L Distribution In Colorado and Wyoming
Preble's meadowjumping mouse(Zapus hudsonius preblei)occurs only in Colorado and Wyoming
(Krutrsch 1954. Long 1965,Armstrong 1972). Historically in Colorado, they are known from the
western edge of the Colorado Piedmont eastward to the South Platte River as far as Greeley. The
soWmem-most occurrence in Colorado is from Colorado Springs(Warren, 1942) in the Arkansas
River drainage. Meadow jumping mice have been found at elevations from 1530 to 1844 m.
Meadow jumping mice are rare in Wyoming and historically they have occurred only in the southern
part of the state and in the Laramie Mountains of soub-dental Wyoming (Long 1965).
Preble's meadow jumping mice have been collected in Colorado from seven counties in the South
Platte drainage(Armstrong 1972)including Adams,Arapahoe.Boulder, Denver,Jefferson, Lartmer,
and Weld and El Paso county in the Arkansas drainage(Warren 1942). In Wyoming,they are
known from Albany, Laramie,and Platte counties(Long 1965). Within this historic range,
distribution,habitat, and populations have not been studied in detail. Only recently have there been
studies that have focused explicitly on meadow jumping mice in Colorado(Compton and Hugie
1993). Until specific investigations were initiated at Rocky Flats and elsewhere, all data were j
compiled from information in natural history collections and results of general inventory studies
bwgedN other small mammals.
Trapping efforts in the past sbc years have increased our knowledge of the distribution of jumping
new in Colorado and Wyoming. These efforts are the result of eoncem about the mouse, and have
been initiated by the U.S. Fish and Wildlife Service, Rocky Fiats Environmental Technology Site,the
Colorado Division of Wildlife,the U.S.Air Force Academy,Warren Air Force Base, Fort Carson
Mary Reservation, Colorado Department of Transportation. City of Boulder Open Space.Jefferson
County Open Space, and other parks and open spaces. An estimated 80 or more field sites have
been sampled along the Front Range between Laramie County,Wyoming, and Pueblo County,
Colorado. With an untold number of field sites not sampled,it is importaM to recognize the limits of
our knowledge of the distribution of meadowjumping new in these two states. The vast majority of
these trapping efforts have yielded no jumping new,even sometimes along drainages that had
yielded jumprig mice just a few years previously!
The successful sites are from both the South Platte and Arkansas drainage basins and can be
described in terns of seven populations as follows(described from north to south):
1. Warren Air Force Base,Cheyenne,Wyoming. Eight individuals were caphxed during Z2W trap
nights.
2. Hygiene, Boulder Canty. Sbc Individuals were captured during 940 trap nights along St.Viam
Creek,on Boulder Canty Open Space.
3. City of Boulder Open Space, Boulder Canty. Suc separate sites, predominately along Sant
Boulder Creels and associated drainages.have yielded jumping mice. This represents a
compilation of a nu mbar of trapping efforts over a period of 6 years or so.
4. Cold Creek,Jefferson Canty. In 1989.a jumping mouse was captured on Coal Creek in
Boulder County. Numerous subsequent efforts were u>suooessM, urdi a site just southh of
Boulder Canty,on Jefferson County Open Space,yielded two individuals m 1995.
5. Rocky Fiats Ermronmentel Technology Site,Jefferson County. Jumping new were first
captured In 1991,and subsequent years have consistently yielded Chess mice in a number of
drainages.with a particular emphasis on Rock Creek; Rock Creek flows Into Coal Creek
downstream from successful sites discussed above.
6. Plum Creels drainages, Douglas Canty. This includes Indian Creek,West Plum Creek,and
East Plum Creek At least four separate trapping efforts have been nmIved,and a distance of
20 miles(32 km).
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