Riparian vegetation has been greatly modified in Australia since European settlement, including replacement with exotics and complete clearing of streamside vegetation. These modifications can alter light regimes, patterns of seasonal leaf-fall and the palatability of in-stream leaf litter material to aquatic primary consumers with potential flow-on effects on trophic pathways. We determined the C and N stable isotope signatures of biofilm, leaf packs, freshwater macrophytes and riparian vegetation as well as common native and introduced fish (brown trout Salmo trutta, common galaxias Galaxias maculatus, short-finned eel Anguilla australis and ammocoetes of the short-headed lamprey Mordacia mordax) and macroinvertebrate species from reaches of native forest, introduced willows, cleared areas and native revegetation in the Gellibrand River catchment, Otway forest Victoria. Our aims were to determine possible differences between primary producer signatures and to identify whether trophic pathways of different fish species are linked with riparian vegetation, including willows, and/or in-stream primary producers. We expected biofilm to dominate food webs in cleared areas and tested whether signatures differed between willow areas, forest and revegetated areas due to shading, leaf-fall patterns and leaf palatability. Against expectations, biofilm and macrophytes in willow and cleared areas did not have a greater influence on consumer species. Diet input of riparian vegetation and other primary producers was highly variable and calls for further study. Surprisingly, the stable isotope signatures of lamprey ammocoetes (which are considered filter feeders) were very dissimilar to all other consumers and do not reflect any of the diet sources analysed.