Edited sentence: (See Wildlife of Aliso Creek for a detailed explanation on the absence of steelhead.Along with increasing concentrations of nutrients from fertilizer and other substances contained in runoff, algal blooms began to hurt the water quality of the creek, especially above Sulphur Creek Reservoir.As giant reed is not suitable habitat for many species, areas infested by giant reed are biologically dead in comparison with unaffected areas.Despite the massive environmental degradation in the Sulphur Creek watershed, it is not biologically dead yet, and still supports some native species.Fish thrived for a limited time in Sulphur Creek between the introduction of perennial flows and the devastating floods at the end of the twentieth century.Fish were likely nonexistent in the historic Sulphur Creek watershed - even Aliso Creek was intermittent historically, and steelhead trout were found to not have inhabited Aliso Creek even during flow periods, despite claims of some residents.Historically, the Sulphur Creek watershed was mostly hilly terrain consisting of chaparral and coastal sage scrub, with native riparian vegetation, likely consisting of live oak, sycamores, and alders (the namesake of Aliso Creek; Aliso is the Spanish translation of Alder) and other small trees, lined the small and seasonally flowing creek.It can grow extremely fast, removing too much water from the creek, and during flood events, many parts of the giant reed can wash downstream and re-establish themselves as a new colony, increasing the problem.The historically seasonal creek was replaced with a constant flow of polluted water from several large storm drains and many smaller ones.These floods wiped out many of the remaining riparian areas lining waterways in the watershed.With the introduction of non-native species, predominantly giant reed, castor bean and tobacco tree, native plant species in the watershed began to die out