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24 species affected the early life stages of native fishes and adult native fishes were affected by large introduced, predaceous species. One respondent indicated the converse of this question should be asked: ''which native species are not affected by the presence of nonnative species." One respondent felt all native species were affected at earlier life stages. Some respondents felt all natives were "undoubtedly" affected, others were not sure. Some felt the interactions were potential in nature, and more or less significant in degree. Similar . to Question 3, some respondents indicated any interactions were not well documented, and thus were unknown in natural environments. One respondent indicated this question was only conjecture. The abundance and widespread distribution of introduced fish species were cited as reasons why predation and competition were probably occurring. Numerous specific interactions between native and nonnative fish species were provided by the respondents. Using the priority listing of nonnative fishes provided in Table 3, the input of the respondents is summarized below by interaction and nonnative species: Predation Channel catfish: -- all native species affected, especially from larvae through juvenile stages. Colorado squawfish and razorback sucker were identified as affected species, especially early life stages of both. Two respondents indicated other native species were affected including roundtail chub, tlannelmouth sucker, bluehead sucker, and all Gila spp. life stages. One respondent indicated this species as prey affected Colorado squawfish; another indicated this was not an important interaction. Red shiner: affected all native fishes ill the larval stage; especially young of Colorado squawfish and razorback sucker. Northern pike: all native fishes affected, including YOY and juvenile forms. Colorado squawfish, razorback sucker, roundtail chub, tlannelmouth sucker, and bluehead sucker were specifically named. Common carp: eggs and larvae of all native fishes affected, especially razorback sucker and Colorado squawfish. Eggs, larvae and young of razorback sucker were mentioned numerous times as a specific impact. Green sunfish: mostly larvae and young of all native fishes, but particularly Colorado squawfish and razorback sucker were impacted. This impact was exerted primarily in backwater habitat. Fathead minnow and sand shiner: these two species affected young forms of razorback sucker and Colorado squawfish, but included all larval native fish as probable prey.