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Aquatic insects of an intermittent stream on the San Joaquin Experimental Range, Madera County, California.
The structure of intermittent streams has been described by Abell (1956) . Her work was based on the analysis of Dry Creek, Fresno County, California, which she considered a typical intermittent stream. An earlier work (Stehr and Bransen, 1938) had given the faunal makeup of a similar stream in Southeastern Ohio. The effect of drought on the fauna of two small mountain streams turning them into intermittent streams is described by Hynes (1958) and Kamler and Riedel (1959). The apparent patterns of recolonization of temporary streams with the return of water is discussed by Abell (1956), Clifford (1966) and Harrison (1966), and a generalized overview of the subject of intermittent streams is presented by Hynes (1972). A tributary of Cottonwood Creek, which unlike Dry Creek has no permanent pools, was followed from November 20, 1972, just after the first rains, until the stream dried up on June 15, 1973, to establish the diversity of insect forms, their temporal sequences and to permit speculation on reinvasion patterns and habitat preferences or limitations. Samples were taken once every other week with a surber sampler and an aquatic net. Stream current was measured with a Gurley Pygmy Current Meter. The stream proved to have a diverse insect fauna as well as a variety of other forms including molluskans, annelids, acarines, crustaceans, amphibians and reptilians. One fish, Gambusia sp., was taken, a likely contaminant from year-round water sources near the stream.