Avian Use of Norris Hill Wind Resource Area, Montana

Avian use and mortality in a proposed wind resource area and vicinity in southwestern Montana were investigated. The primary objective was to collect pre-impace information on various parameters of avian use in and around Norris Hill Wind Resource Area for comparison with similar data collected post-impact, should NHWRA be developed. Secondary objectives included a description of thespatio-temporal profile of seasonal use in and near NHWRA and an evaluation of the efficacy of monitoring techniques for describing avian movements. A Before-After Control-Impact study design was used to initiate impact analysis, with results of this study serving as Before-Impact and Before-Control data. During monitoring of seasonal migrations, parameters of avian use were recorded 'In' and'Out' of NHWRA. The primary technique for detecting avian movements was employment of two marine surveillance radars. Visual observations and radar were used throughout the study, testing the detection capability of each. Radar excelled at detecting birds but species or number could not be identified, except subjectively. Detailed data are provided in the report. Equipment, operation, dataneeds, and monitoring efforts for future study are addressed.