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<br />i <br />This adds some confusion to the report because different population estimators were used, and <br />more emphasis was placed on bonytail growth. <br />STUDY AREA <br /> <br /> <br />Enclosures designed to hold larval fish were constructed at The Stirrup floodplain <br />wetland on the Green River (River Mile [RM] 276.0) near Vernal, Utah. <br />METHODS <br />Study site and enclosure design <br />~ During high river flows when the site inundates, The Stirrup ranges between 8.1 and 13.8 <br />surface hectares at river flows of 13,000 ft3/s (368 m3/s) and 24,000 ft3/s (680 m3/s) respectively <br />(USGS gage at Jensen). The Stirrup retains sufficient water throughout the year to support fish <br />~ when peak river flows exceed 14,000 ft3/s (396 m3/s) for several weeks. However, peak flows <br />have recently not exceeded 14,000 ft3/s (396 m3/s) and the site completely dried in 2001. In <br />2002, flows were again inadequate for natural inundation. Consequently, for this study, water <br />t was pumped into the site from the river. After one week of pumping, approximately 1.0 m of <br />water depth was achieved. To maintain water level, pumping was reinitiated periodically during <br />the remainder of the study. <br />~ Two, 22.9 m x 45.7 m (0.10 hectares) and one 4.9 m x 4.9 m enclosures were built at The <br />Stirrup site in March and Apri12002. The enclosures were essentially a steel post and wire <br />fence, similar to a livestock pen. They were constructed with two-meter steel fence posts, with <br />~ four layers of fencing material. The four layers were: a solid tarp that was impervious to all <br />organisms, 0.1016 cm mesh window screen, 0.635 cm hardware cloth, and 4.88 m x 1.219 m <br />heavy galvanized wire fence panels. The tarp layer was removed, as the fish grew large enough <br />~ to be contained by the window screen. This allowed better circulation with water outside the <br />enclosures. <br />3 <br />