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I I I I I I I I I I I I I I I I I I I DISCUSSION The macro invertebrate abundance in the lower Escalante have not been previously studied. The upper reaches above the confluence of The Gulch and the Escalante River and tributaries were sampled incidental to a survey of threatened and endangered fish (McAda et al. 1977). That study showed that Baetis sp. was ubiquitous throughout the sampling area and Rhyacophila sp. dominated headwaters, where as Tipulids and Anisopterans were more prevalent in the lower reaches of the study area. Vinson (1998) collected samples from the upper reaches of the Escalante River, tributaries and a couple ofTinajas. That study found about 70 taxa. Plecoptera were only collected from Steep Creek, which is a tributary of The Gulch. The Trichopteran Rhyacophila was not collected during the 1998 survey. Rivers naturally change as they flow downstream. Riverain vegetation conditions, light, temperature, hydraulics, and substrate composition all change and in response to these environmental changes macroinvertebrate communities change. The macroinvertebrate abundance in the lower Escalante was low compared to the data collected from the upper Escalante by Vinson (1998). This is not that unusual for river drainages. Vinson sampled in early June when the water level was low. Just before we sampled the lower reaches the water level was elevated. Sampling was confined to the edge of the river due to the high water and scouring could have reduced the abundance. Because this is the first information on macroinvertebrates from the lower Escalante River it begins to establish baseline data against which future data can be compared. RECOMMENDATIONS Inventory: A comprehensive study that samples the macroinvertebrates within the mainstem and tributaries of the Escalante at various times of the year should be conducted. This study should include the entire watershed and should not be confined to NPS lands. The data collected would provide the spatial and temporal information required for selecting water quality monitoring sites within the watershed. Monitoring: As a minimum the NPS should establish a long term monitoring site on the lower Escalante located at the north face of Steven's Arch (UTMx501532y4143206). This site can be accessed by hiking down Coyote Gulch. A suite of physical and chemical parameters should be collected with the macroinvertebrate data to help detect changes in water quality. Other sites might need to be added as information from the inventory is gathered. REFERENCES Bode, R. W., M. A. Novak, and L. E. Abele. 1991. Methods for Rapid Biological Assessment of Streams. New York Department of Environmental Conservation. Albany, New York. 8