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average sagebrush canopy coverage of 14 percent. Martin's (1970) studies also showed that juveniles preferred <br />sites with short sagebrush while adults preferred areas of tall sagebrush. <br />• Forb cover in low and mountain sagebrush communities on the permit area was lower than that found for preferred <br />brood feeding sites in other studies. In studies by Peterson (1970), average forb cover was measured at 33 percent <br />in brood feeding areas. Reduced availability of forbs in sagebrush in the permit area may be compensated for by <br />grouse feeding in cropland, reclaimed pastureland, and fallow fields on the permit area. <br />Several opportunistic observations of grouse were made in cropland habitat during the 1984 field studies. <br />Dandelion (Taraxacum officinale), a preferred food of juvenile grouse (Peterson 1970), appeared to be fairly <br />abundant in fallow fields. In addition, many grouse have been observed on reclaimed pastureland during the fall <br />hunting seasons (1980 -83). Forbs such as lactuca (Lactuca serriola) and yellow sweet clover (Melilotus <br />officinalius) that are abundant on some of the newly reclaimed pastureland were the predominant food found in the <br />crops of harvested birds. <br />Stands of mountain (big) sagebrush, particularly those in close proximity to leks, provide suitable nesting habitat. <br />Studies by Wallestad and Pyrah (1974) in Montana showed that 68 percent of all nests located occurred within 2.4 <br />km (1.5 mi) of the lek. Studies by Authenrieth (1976, as cited in Braun et al. 1977) in Idaho indicated that distance <br />of nests from leks varied depending on the proximity of the lek to quality nesting habitat. In his studies 85.0 <br />percent of the nests were within 6.4 km (4.0 mi) of the lek, 97.2 percent were within 9.7 km (6.0 mi), and all nests <br />found were within 12.5 km (7.8 mi) of a lek. Patterson (1952) and Gill (1965) found that 92 percent of the nests <br />located occurred under sagebrush plants. All the nests located by Wallestad and Pyrah (1974) occurred beneath <br />sagebrush plants. Sagebrush communities used for nesting are characterized as ranging between 17 and 79 cm <br />(6.7 -31.1 in) in height (with nests usually under the tallest bushes available) and exhibiting a canopy cover of 20 to <br />40 percent (Patterson 1952, Klebenow 1969), Wallestad and Pyrah 1974, Petersen 1980). In addition, Wallestad <br />and Pyrah (1974) found, when comparing successful to unsuccessful nests, that successful nests were located in <br />• stands of sagebrush with a higher average canopy cover (27 percent) than those of unsuccessful nests (20 percent). <br />Taller sagebrush stands also may provide a food supply to grouse after early snows cover the shorter sagebrush <br />communities, although, Gill (1965) found that birds in his study preferred to feed on the short (less than 11 in), less <br />vigorous sagebrush plants. He postulated that grouse preferred shorter, less vigorous sagebrush since these shrubs <br />exhibited significantly lower levels of essential oils in their foliage than the taller (greater than 11 in), more <br />vigorous sagebrush plants. <br />Sagebrush/meadow communities become valuable forage sites for grouse as summer progresses and forbs dessicate <br />in the dryer, more upland, mountain and low sagebrush communities. Two authors, Savage (1969, as cited in <br />Autenrieth et al. 1982) and Oakleaf (1971, as cited in Autenrieth et al. 1982) have suggested than, in Nevada, mesic <br />upland meadows are important summer habitats for young broods, and that they provide a source of food (forbs), <br />water, and cover unavailable in more xeric adjacent rangelands. Vegetation information (see Response to Rule <br />2.04.10) presented in this permit application shows that forb production in sagebrush/meadow (37.9 g /m2) was <br />greater than that in the two upland sagebrush communities (22.6 g /m2). This difference in forb production is likely <br />to become more pronounced as summer progresses and moisture decreases in the upland communities. In most <br />areas the sagebrush/meadow community is also a source of surface water for grouse. <br />Throughout their range, studies of sage grouse food habits have documented that they are solely dependent on <br />sagebrush from October through April (Dargan et al. 1942, Patterson 1952, Klebenow and Gray 1968, Peterson <br />1970). In May, sage grouse shift to a forb - dominated diet and then shift back to sagebrush in September. Use of <br />sagebrush communities by sage grouse during these months is controlled primarily by snow cover and the <br />availability of uncovered sagebrush. In Montana, Eng and Schladweiler (1972) found that sage grouse winter range <br />was characterized by large expanses of dense sagebrush (over 20 percent canopy coverage) on land having little if <br />any slope. Beck (1975) and Gill (1965) concluded that selection of wintering areas is dependent on snow <br />. accumulation and that grouse avoided areas where sagebrush was not available above snow cover. Gill (1965) <br />observed winter concentrations of grouse in areas of rolling or broken topography where wind -swept ridges were <br />free of snow. Winter concentrations of grouse in Beck's (1975) study were found primarily on west, southwest, <br />RN08 -05 2.04 -65 03/12/10 <br />