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18/ Riparian Ecosystem Recovery measured by placing a square or dot grid over the area that is delineated on the map; the number of squares (or fractions of squares) or dots that lie in the watershed area are then counted. Methods for measuring watershed size are reviewed in detail in documents such as Gordon et al. 1992. Land Uses in the Watershed Understanding the watershed's land use history is a significant step toward understanding the trend of the landscape, the reasons behind the decline of its riparian ecosystems, and the potential for recovery. Going back to the time when the watershed was first influenced significantly by Anglo-American set- tlement is often sufficient for understanding how the watershed has been most affected by human activities. For the Rincon Creek watershed, for example, information describing its land use history is being collected from the turn of the century, when Anglo-American settlement patterns and livestock use be- came significant. Ecosystem managers should also consider how land use activities in the watershed may diange in the future. Although currently in a rural setting, the Rincon Creek reach that is being evaluated for recovery (case study 1) passes through landscapes that are likely to experience extensive development in the near future. To be effective, the Rincon Creek recovery project needs to take into consideration how such a dramatic change in land use will affect factors such as sediment and water runoff, groundwater levels, and channel stabil- ity - factors that can significantly affect the outcome of a riparian recovery effort. In addition, ecosystem managers may have to design the recovery proj- ect so that it meets the aspirations of the developing community. This, of course, affects not only the riparian recovery strategy that is ultimately devel- oped, but the overall objective of the project as well. Drainage Density Drainage density is an expression of how a watershed is dissected by its drain- ages (Toy and Hadley 1987) and is calculated by dividing the total stream length for the watershed by the catchment area: D _ LL d- A where Dd is the drainage density, LL is the total channel length, and A is the catchment area. Channel length is commonly measured directly off of