BIRD USE OF RIPARIAN VEGETATION ALONG THE TRUCKEE RIVER, CALIFORNIA AND NEVADA

The Truckee River in California and Nevada is subject to diverse water regimes and a corresponding variety of now rates. Original riparian v egetation has been altered by these variable flow rates and by a varie ty of human uses resulting in loss of native riparian vegetation from its historic extent. We conducted bird surveys along the Truckee River during spring 1993 to (1) determine relationships between birds and t he present vegetation; (2) determine the importance of different veget ation types to sensitive bird species that have declined recently in t he western United States due to competition from exotic plant species, cowbird (Molothrus ater) parasitism, reduction in nesting habitat, or other unidentified reasons; and (3) establish a monitoring program an d collect baseline data for future comparisons. The most frequently de tected bird species throughout the study was the Brown-headed Cowbird. The greatest number of bird species (98 of 116) was found in the nati ve mixed willow (Salix spp.) riparian scrub vegetation type. We recomm end protecting the remaining native riparian vegetation types for bird habitat along the Truckee River.