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Name Date
Landis Evaluation of Aquatic Habitat at Stream Restoration Project Sites in the Ashokan Watershed
Stream restoration is ongoing in Catskill mountain streams because of their value as drinking water to New York City. Past restoration projects focused on stabilizing the streams to buffer high flow events and decrease erosion; however, less focus has historically been placed on habitat for aquatic organisms. More recently has there been a focus on these organisms. Dave Rosgen created a Salmonid Index to measure and score stream geomorphology and physical features to understand trout habitat across 5 different life history stages. Our goal was to evaluate the Rosgen Salmonid Index (RSI)for use in Catskill streams. Five stream reaches were selected for sampling, 2 degraded sites, 2 reference sites, and a restored site. We measured each reach longitudinally, created cross section profiles, sampled invertebrates, conducted pebble counts, and estimated a number of physical habitat variables. We found that the two reference sites scored the highest in the overall index, while the restored site scored the lowest. We found that there was no correlation between the abundance of invertebrates and the sub-index for invertebrate habitat quality, but found a significant relationship with entrenchment ratio. Because the RSI matched our expectation that visually stable stream reaches scored higher, we concluded that Rosgen’s salmonid index will be a helpful tool for assessing trout habitat in Catskill streams. We recommend that improvements could be made to the index by transition several of the physical habitat observations to quantitative metrics. The addition of the RSI to existing stream sampling protocols should not result in a significant increase in work, if fluvial geomorphological data is already being collected. Perhaps the greatest value of the RSI is that it provides a clear guide to physical habitat variables that can be added to stream restoration project design to maximize the benefit for trout.