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

. I
VIL Description of Riparian Physical System
Most of the worts on habitat presented in this report has concentrated on the analysis of vegetation.
There is a need to complement these biotic data with a more complete description of the physical
factors with which meadow jumping mice are associated. Thee have been no formal analyses of
the differences and similarities among the sites presorted here. Such landscape scale comparisons
can be valuable in identifying and selecting sites for many purposes(e.g. probable surveys,
restoration). The group has discussed the need for worts at the regional or landscape scale,
especially in the analysis of physical variables. Most of the shidies to date naturally concentrate on
small areas and sites where the mouse has been captured;typwalty this may be a linear riparian
cone of a few hundred meters length to a kilometer or so. A landscape approach would allow the
investigator to characterize variables within an entire drainage area,and this larger scale picture may
be key to understanding the impacts Mat affect mouse dW ibufion and dispersal. Analyzing entire
drainages is probably also appropriate for this mouse;mlduvestem Zapus hudsonius have shifting
home ranges, are known to travel long distances,and are opportunistic isde in their foraging habits
(Quimby. 1951). They have been observed to move in response to charges in seasonal water
supply, and many of the drainages sampled in Colorado are ephemeral:small seeps springs,and
cow variable hydrological conditions in these drainages may provide seasonally important habitat
One way of analyzing physical and biotic data at large scales is through the use of geographical
information systems(GISs). GIS analysis has been performed on habitat data from at least two
sites:City of Boulder and Rocky Flab. These analyses can be used to explore areal extent of
vegetation types, reiatiorstnfps of vegetation patches(polygons)to one another,and average
distances to mapped features(streams),among other analyses. These analyses may be very
revealing at the site level, but there is still a need to examine the similarity and dissimilarity of many
sibs at the landscape level. One of the greatest utilities of using a GIS approach is that multiple
conditions can be set for several variables simultaneously,and an integrated habitat model can be
determined.
The objectives of using a GIS approach Induce:
• New habitat data may become available. Electronic data may be available for sites where they
have been difficult or impracticable to collect.
• Regional habitat pattems may be determined by setting conditions for the variables of interest
and performing GIS analysis.
• GIS analysis can determine averages or ranges of sew variables,and these coriftons can
be used to select new sites with the same conditions.
The knowing list of variables would be useful for this approach:
soil type(s).lardforms(slope):
stream ordedother hydrological information:
lard ownership,and
lard use(past and present,if data are available).
This information maybe used to evaluate several questions of practical inteest such as
• Are there any apparent differences among FWs(1998)historical sites and sites where the
mouse has been found in the past 10 years?
• What areas or sites should be prioritized for future searches?
• Can critical habitat be designated using this approach?
• What areas are suitable for restoration?
• Will land ownership affect management and possible enforcement actions?
• What effect does land use have on mouse distribution?
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