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2.2.3 Songbirds <br />• Songbirds and songbird-like birds were surveyed using both qualita- <br />five and quantitative methods. Qualitative observations were recorded <br />during all field activities; special effort was made to qualitatively <br />survey habitat edges and small patches of unique habitat (e.g., ponds) <br />to provide a more comprehensive inventory of species in. the study area. <br />Quantitative surveys were conducted in four habitat types (aspen, sage- <br />brush, mountain shrub, and wet meadow) using a specific-width strip <br />transect method modified from several authors (Balph, Stoddard, and <br />Balph 1977; Emlen 1977; Franzeb 1977; and Dickson 1978). Locations of <br />transects are provided on Figure 2.1.1-1. This method provided indices <br />of avian density which were then used to calculate relative abundance <br />and species diversity. <br />Field procedures for the quantitative transects were as follows. A <br />single 800 meter transect was located in a homogenous section of each <br />habitat type. On three mornings between May 31 and June 5, an experienced <br />ornithologist slowly walked each transect and recorded all birds seen or <br />heard according to their perpendicular distance from the center line <br />(0-10 ft; 10-25 ft.; 25-50 ft.; SO-100 ft.; 100-200 ft.; 200-400 ft.). <br />Flyovers and birds farther than 400 feet from the centerline were recorded <br />as qualitative observations only. All transects were surveyed during <br />periods of peak bird activity (within 3.5 hours after sunrise) during <br />favorable weather conditions. <br />Density indices were calculated based on the effective detection <br />distance (EDD) for each species in each habitat type. The EDD is defined <br />as the distance in which all individuals of a species are assumed to <br />• have been detected by the observer and is used to define the effective <br />