Thesis - Open Access
Master of Science (MS)
Wildlife and Fisheries Science
The habitat of nesting and brooding sharp-tailed grouse (Pedioecetes phasianellus) was studied 1 April to 25 August 1973 and 1974. The objective of the study was to determine the quality and quantity of vegetation at nest and brood locations of sharp-tailed grouse in relation to available vegetation within pastures. Five range sites, lowland draw, rolling grassland, upland grassland, rocky outcropping, and claypan were studied. Thirty-four females were trapped on dancing grounds and equipped with radio transmitters. Seventeen nests were located by monitoring the movements of transmitter-equipped hens and 26 nests were located through use of cable-chain drag. Height of vegetation was measured at nest sites, at sites where broods were located, and in pastures and range sites with the visual obstruction pole. Species composition, relative frequency, and relative density of vegetation were measure at nest and brood locations using the inclined-point quadrat-method. Regrowth, tame, and native vegetation types were utilized most frequently by nesting and brooding sharp-tail hens. Most nests and broods were found in the rolling grassland range-site. Most nesting sharp-tails were observed in pastures under a deferred-rotation grazing system. Average visual obstruction reading (VCR) was greater than 2.0 at 40 of 43 sharp-tail nests and at least 3.0 for over 75 percent of the brood locations. Vegetation height declined as distance from the nest and brood sites increased to 7 m. Height of vegetation at nest sites was significantly different (p<0.01) at varying distances and directions from the site. Vegetation height at nest and brood locations was correlated to the overall-average vegetation height in rolling grassland range site within pastures during 1973 and 1974. Native grasses occurred most frequently at nesting and brooding areas. Woody plant species were more frequently utilize by broods than nesting hens. Wolfberry (Symphoricarpos occidentalis) was the only woody species found at nest sites. Use of cover by sharp-tail broods depended upon time of day, habitat available, climatic factors, and amount of disturbance. Hens with broods were found in short-growing vegetation immediately after sunrise and in taller vegetation later in the morning. Relative frequency and density of plant species at nest sites changed at various distances from the sites in 1974. Hens nesting in a particular habitat type were usually surrounded by additional vegetation of the same type. Percentages of the various habitats within 0.4 km of the nest site indicated hens were nesting in areas where on habitat type contained over 50 percent of the area. A significant difference (P<0.01) in vegetation height was found between pastures and between range sites within pastures in 1973 and 1974. Most pastures sampled in 1974 had taller vegetation than 1973 after the vegetative growing period. Most pastures had taller vegetation in the fall of the year than in the spring. Grasslands on the Gorham area could be managed for grazing and sharp-tail habitat by measuring and evaluating cover in range sites as well as in pastures. A management program that increased the average height of vegetation in pastures (minimum VOR of 1.5 within pastures) in the spring would provide taller vegetation for nesting hens and good brooding areas in the summer.
Library of Congress Subject Headings
Number of Pages
South Dakota State University
Kohn, Stanley C., "Sharp-Tailed Grouse Nesting and Brooding Habitat in Southwestern North Dakota" (1976). Theses and Dissertations. 152.