Monitoring of adult intermittent stream insects in Curry Creek Canyon

California is characterized by a mediterranean climate, in which hot, dry summers, are followed by cool, wet winters. Many mediterranean climate streams have intermittent flows in which the streams dry completely during the summer months and water only appears as isolated pool habitats. In winter, streams have high magnitude, flashy flows. Despite these extreme drying and flooding events, these intermittent streams can be highly diverse in the number of species.

Curry Canyon Creek, a stream located on the east side of Mt. Diablo, offers the opportunity to explore life history and phenology of intermittent stream insects. The stream is part of 1,080 acre ranch recently acquired by Save Mt. Diablo, and was the largest remaining unprotected canyon on Diablo’s main peaks, between the Diablo summit and the Blackhills.

This project samples, identifies and databases riparian* insects in a 1 km section of Curry Canyon Creek. The purpose for collecting and identifying insects on the preserve is twofold: 1) to survey for insects monthly to add to the baseline biological inventory of Mt. Diablo stream habitats on Save Mt. Diablo lands and 2) to monitor the relationship between streamflow status and the presence of different aquatic species. Specifically, we characterize species diversity and life cycle timing. To accomplish these goals we will use ultraviolet light traps (“blacklighting”) to collect adults and in-stream samples to monitor larval growth and development.

Year-round sampling of adult aquatic insects is rarely undertaken, yet is critical to understanding species richness. This documentation of life stages of the aquatic species in the stream over time will give insight into when the steam may be most sensitive to disturbance. Identification of these periods of sensitivity can be important in planning management activities, especially in rangeland ecosystems.