Relationships between forest songbird populations and managed forests in Idaho

Abstract

Many species of songbirds have experienced population declines in the eastern U.S. in recent years, but conclusive data on population trends and factors affecting populations in the West are lacking. Few studies have evaluated the importance of surrounding land configuration to songbird abundances. In 1992, we initiated a study in mixed conifer forest in west-central Idaho to compare songbird composition and abundances among two untreated watersheds and three watersheds having clearcuts. Watersheds were selected on the basis of their la-rge size, accessibility, dominant tree type, and timing and extent of management. Based on 1992 point counts of 29 selected bird species, we identified four species that had significantly lower mean birds/count station in managed study areas than in untreated areas. These were hermit thrush (Catharus guttatus), Swainson's thrush (Catharus ustulatus), pileated woodpecker (Dryocopus pileatus), and warbling vireo (Vireo gilvus). Twelve species were significantly more abundant in clearcut watersheds than in untreated watersheds, whereas abundances of 13 species did not differ between treated and untreated study areas. Variation in bird species richness among study areas may have been influenced by sampling intensity. Negative or positive responses to management were not clearly associated with migratory status. We discuss 1993 modifications to our study design and future use of a Geographic Information System (GIS) to measure landscape characteristics.

Parent Publication

• Sustainable ecological systems: Implementing an ecological approach to land management

Citation

Evans, Diane M.; Finch, Deborah M. 1994. Relationships between forest songbird populations and managed forests in Idaho. In: Covington, W. Wallace; DeBano, Leonard F.; tech, coords. Sustainable ecological systems: implementing an ecological approach to land management. 1993 July 12-15; Flagstaff, Arizona. Gen. Tech. Rep. RM-247. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Forest and Range Experiment Station. p. 308-314.