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(later re-identified as Zapus hudsonius). This single individual from riparian shrub
<br /> vegetation represented 0.3% of captures all captures in the study. According to C.
<br /> Miller (personal communication) the specimen was taken at sample site 12, which is
<br /> along Spring Brook, NW 1/4 NW 114 sec. 31, T. 1 S, R. 70 W.
<br /> In addition to captures in Boulder County, a number of specimens have also been
<br /> taken in recent years from Rocky Flats, in Jefferson County just south of the Boulder
<br /> County line (see Stoecker, 1992; Harrington et al., 1995).
<br /> It is of possible importance that a number of studies of small mammals along and east
<br /> of the mountain front in Boulder and adjacent Jefferson counties have failed to reveal
<br /> the presence of meadow jumping mice. For example, Averill and Damas (1994a)
<br /> studied the Schneider/Nejerschleb Parcel, City of Boulder Open Space (west of US 36
<br /> and south of Beech Aircraft) without capturing the species in 480 trap-nights. Similarly,
<br /> Averill and Damas (1994b) studied the Tracy Collins Parcel (south of the junction of
<br /> Colorado highways 93 and 128, north of Rocky Flats) and did not capture the animals
<br /> in 480 trap-nights (in contrast to results of Dawson, 1989).
<br /> Colvin (1970) studied behavior of species of Microtus in the Boulder area. He reported
<br /> no captures of meadow jumping mice in the course of trapping his laboratory stocks of
<br /> voles, although he worked in apparently suitable habitat. Brown (1980) reported an
<br /> extensive study of small mammals on the northeastern part of the Rocky Flats Buffer
<br /> Zone (SE 1/4, SW 1/4 sec. 23, T 2 S, R 70 W, 5900-6010 ft., Jefferson Co.). Her study
<br /> involved nearly 9000 trap-nights through all seasons over 20 months in 1978 and 1979
<br /> and included habitat types that have produced captures of meadow jumping mice in
<br /> recent years. She did not trap Z. hudsonius.
<br /> Armstrong and Freeman (1982) described reconnaissance studies of small mammals of
<br /> Boulder Mountain Parks, using 50-trap transacts arranged as in the present study (see
<br /> Methods). Localities trapped included the following: A. plains grassland, S end Mesa
<br /> Trail, 10-11 September, 29-30 October (2 nights x 4 transacts x 50 traps = 400 trap-
<br /> nights); B. ponderosa pine woodland, S end Mesa Trail, 25-26 September (1 night, 200
<br /> trap-nights); C. woodland/grassland ecotone, above NCAR, 25-26 September, 1 night,
<br /> 200 trap-nights); D. mixed coniferous forest, near S end Mesa Trail, 25-26 September
<br /> (1 night. 200 trap-nights); E. aspen woodland/ montane riparian, Long Canyon, 7100 ft.,
<br /> 1-2 October (1 night, 150 trap-nights); F. montane riparian, Gregory Canyon, 6200 ft.,
<br /> 15-16 October, (1 night, 200 trap-nights); G. foothills scrub, Gregory Canyon, 15-16
<br /> October (1 night, 100 trap-nights); H. plains riparian woodland, S Boulder Creek, 5600
<br /> ft, 16-17 October (1 night, 200 trap-nights); I. talus, base of Third Flatiron, 22-23
<br /> October, (1 night, 200 trap-nights). A number of these sites (especially A and H)
<br /> contained habitat that was seemingly suitable for meadow jumping mice, but Z.
<br /> hudsonius was not captured on any of the transects.
<br /> Armstrong and Freeman (1984) did not capture meadow jumping mice in a 1983 study
<br /> of small mammals of the "Boulder Creek Cottonwood Grove," along Boulder Creek
<br /> between 47th and 55th streets. Armstrong (1987) reported on reconnaissance of small
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