The U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, conducted a 20-month study during 1988-90 to evaluate the effects of episodic acidification on fish and aquatic invertebrates in pristine headwater streams in the Catskill Mountains of New York. The study was part of the Episodic Response Project, a regional survey of episodic acidification by the U.S. Environmental Protection Agency, and was carried out simultaneously with other studies in the Adirondack Mountains of New York by the Adirondack Lake Survey Corporation and in central Pennsylvania by Pennsylvania State University. This report summarizes the methods used, describes the sampling sites, and presents the data collected from October 1, 1988 through May 30, 1990 at four headwater watersheds (Biscuit Brook, East Branch Neversink River, Black Brook, and High Falls Brook). The study entailed (1) monitoring the quantity and chemical quality of atmospheric deposition and the quality of discharge of streams, and (2) experiments to determine the effect of stream-water-quality changes on fish and invertebrate populations.
