Enhancement actions that will benefit chum salmon include improving access to spawning areas through barrier removal, improving the quality of spawning habitat, maintaining flows over redds sufficient for flushing and oxygenating gravels, and enhancing riparian vegetation to maintain bank stability and decrease sloughing of banks and siltation. Enhancement projects that maintain adequate quantity of spawning habitat and substrate type: Freshwater limiting factors for eulachon are largely restricted to river conditions and spawning, with a lack of appropriate sand and pea-sized gravel substrate being the most likely limiting factor. Eulachon are present in the mainstem Chehalis River, as well as the Wynoochee and Satsop rivers. Once juveniles emerge from the substrate, they are flushed out of the natal reach with river flow. Enhancement actions that maintain an adequate quantity of sand and pea-sized gravel areas for spawning will benefit eulachon. 
Enhancement projects that involve control of non-native predators through targeted removals: For Olympic mudminnow, removal of non-native predators, such as largemouth and smallmouth bass, from oxbow lakes and side-channel habitats, will benefit the species. This might be accomplished by targeted harvest of predator species through changes in harvest regulations (season length and daily catch limits), fishing derbies and reward programs, and selected trapping. However, the effectiveness of these approaches on Olympic mudminnow is untested, and responses to their application are uncertain. Hence, any attempts at their application should involve monitoring that can adaptively track the results and provide direction to improve any future attempts at applications. A large part of this uncertainty is based on whether the locations targeted for enhancement are associated with the in-stream main channel Chehalis that is non-native dominated, and whether side-channel reconnection is also part of the enhancement. If the in-stream main channel Chehalis is not non-native-dominated, then non-native removal would likely be a success if side-channel reconnection is also part of the enhancement. If the in-stream main channel Chehalis is non-native-dominated, then the success of non-native removal would be uncertain if side-channel reconnection is part of the enhancement. In the latter instance, it would be critically important to adaptively track (monitor) the results of the enhancement action. The creation of preferred habitats for species will reduce the potential for further contractions of their distribution and range.
Based on existing information, our ability to quantify the potential benefits of these actions to most Other Fish Species is limited, as enhancement science has focused on culturally and economically important fish species, such as salmon. As pointed out in Chapter 5 of the ASEP report, available information on the species discussed here is too sparse to inform population trends or, in many cases, to identify their ecological constraints. Therefore, a critical and necessary precursor to enhancement actions on most Other Fish species is inventory of aquatic habitats to understand where they occur in the basin and the status of their populations. Even after habitats, sites, or projects for potential enhancement actions are identified, it is crucial that their application be monitored, because of the uncertainty associated with responses, especially for Other Fish species that occupy side-channel habitats, where almost no data exist. This will ensure that attempted enhancements can contribute meaningfully to future efforts, should they not succeed.
IMPACTS OF ENHANCEMENT ACTIONS ON NON-FISH SPECIES To an even greater degree than for Other Fish Species, available information on Non-fish Species is too sparse to precisely direct enhancement activities that will positively benefit them, particularly since the balance of the Non-fish Species occur in the most ignored macrohabitat of the floodplain, the side-
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