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Once larvae have been entrained into a wetland in sufficient densities and survive, <br />these juveniles or adults need to recruit back to the river. This requires the wetland to <br />persist with sufficient water quality and depth to allow survival of remaining razorback <br />sucker and bonytail until they can access the river during spring river-floodplain <br />connection. These variables and habitat conditions should be investigated and <br />synthesized to outline management actions necessary to aid recovery. <br />Survival estimates indicate that fall survival of larval razorback sucker is <br />independent of nonnative fish densities. This is consistent with the reset theory. The <br />adult fish, primarily fathead minnow, red shiner, green sunfish and black bullhead, <br />entrained along with larval suckers during the initial flooding of the wetland are the <br />primary fish predators on larval razorback sucker. Once larval razorback sucker are <br />entrained in the productive wetland, they are able to grow fast enough to avoid predation <br />by numerous YOY nonnative predators produced in the wetland. <br />The use of enclosures to maintain tighter control over the experiment presented <br />some problems during this study. In 2004, many nonnative fish in excess of those <br />stocked were collected in the control enclosures indicating that the enclosures were not <br />completely secure. Escapement of bonytail was observed and therefore escapement of <br />razorback sucker larvae was also very likely. However, razorback sucker were not <br />captured during sampling outside of the enclosures. Presumably, escapement was <br />minimal, with the exception of bonytail introduced in 2003 prior to water overtopping the <br />enclosures. Escapement causes the survival estimates to be conservative. However, we <br />feel it did not affect conclusions of this study. <br />21 <br />