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<br />""', III. WILDLIFE HABITAT MONITORING AND EVALUATION
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<br />SALINITY PROJECT AREA DESCRIPTION
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<br />The Lower Gunnison Unit monitoring and evaluation area is
<br />characterized by a dominance of irrigated cropland, pasture land and
<br />hayland, interspersed with native rangeland on 'mesas, high terraces
<br />and old alluvial deposits. Elevation ranges from 4,500 to 7,000 feet,
<br />with average annual precipitation ranging from less than 8 inches to
<br />over 12 inches. A diversity of small grain, fruit, vegetable and
<br />forage crops are produced on irrigated fields. Irrigation water
<br />delivery systems (earthen ditches and canals) are interspersed
<br />throughout the area. Range sites include salt 'flats, and clayey,
<br />silty, and loamy saltdeserts. Plant species associated with these
<br />range sites include black greasewood (Sarcobatus vermiculatus), basin
<br />big sagebrush (Artemisia tridentata tridentata), shadscale (Atriplex
<br />confertifolia), four-wing saltbush (A. canescens), ,Gardner saltbush
<br />(A. gardneri), alkali sacaton (Sporobulus airoides), basin wildrye
<br />(Elymus'cinereus), saltgrass (Distichlis stricta),galleta (Hilaria
<br />jamesii), Indian ricegrass (Oryzopsis hymenoides), and bottlebrush
<br />squirreltail (Sitanion hystrix).
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<br />HABITAT CONCERNS
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<br />Habitats of concern within the Salinity Project Area are
<br />associated with the irrigated fields, tail water run-off and
<br />irrigation water delivery systems. Through improved irrigation and
<br />drainage systems (i.e. underground pipe, concrete lined ditches, gated
<br />pipe and drip type irrigation systems) and irrigation water management
<br />on fields, a loss of wildlife habitat is expected to occur.
<br />Due to inefficient irrigation, areas within and below fields are
<br />often invaded by hydrophytic species such as sedges (Carex spp.) and
<br />rushes (Juncus sPP') , cattail (Typha latifolia), bulrush, (Scirpus
<br />spp.), reed canarygrass (Phalaris arundinacea),. common reed
<br />(Phragmites communis), saltgrass, willow (Salix spp.), chickory
<br />(Cichorium intybus), and plantain (Plantago spp.). According to
<br />Circular 39, these areas are classified as irrigation induced type 1,
<br />2, 3, 6, 9, and to a lesser degree type 4 wetlands. For this report,
<br />wetlands will be classified according to U.S. Fish and Wildlife
<br />Service Circular 39, 1956.
<br />Wetland (as that mentioned above) and upland vegetation '(shrubs,
<br />trees, and annual and perennial forbs and grasses) associated with on-
<br />farm earthen ditches and field borders (uncultivated areas) are of
<br />concern in terms of wildlife habitat. Off-farm irrigation water
<br />conveyance systems which support upland, riparian and wetland
<br />vegetation provide valuable wildlife habitat. Interspersion of these
<br />habitat types with cropland, pasture land and hayland, increase edge
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