Estuaries and other shallow coastal embayments function as nursery areas for various fish species. Their productivity is often at risk from natural and anthropogenic habitat alterations. In Elkhorn Slough, levee breaches during the 1980s have increased the tidal volume and tidal currents, and have exacerbated already high rates of erosion throughout the slough. To assess the potential impacts of erosion on fish trophic ecology, feeding habits were analyzed at four stations which have experienced different rates of erosion and compared to data taken in the 1970s, before the increased rates of erosion, by Barry et al. (1996). Of nine fish species in both these studies, significant differences were found in the diets of topsmelt, Atherinops affinis, and two prior polychaete and mollusc feeders: the English sole, Pleuronectes vetulus; and the white surfperch, Phanerodon furcatus. Notable differences in diet were also found for the northern anchovy, Engraulis mordax. Overall, the diversity of fishes diets has decreased since the 1970s, due to increased importance of epifaunal crustacea and detritus and lower emphasis on polychaetes and molluscs. Similar results were found for the combined feeding habits of fishes at each station. Comparison of fish diets among stations indicated the station experiencing the least erosion, Rubis Creek, had diets more similar to what was documented during the 1970s. Diets of fishes at stations with higher rates of erosion, were more greatly altered over time. Data on sediment characteristics showed that grain size was similar among stations, and the sediment particle distribution has shifted toward firm clay. Invertebrate assemblages also changed at stations experiencing erosion. Densitiesof invertebrates were significantly lower during the present study, the relative abundance of infaunal worms decreased over time, and the invertebrate assemblages are now dominated by epifaunal crustacea. The results of this study indicate that increased rates of erosion associated with elevated tidal flushing has resulted in a more homogeneous system as fish species shift their diets to fewer available prey.