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natural situation, initial species composition and relative abundance could vary greatly <br />from year to year depending on several factors and chance alone. The main factors that <br />likely influence the number and species composition of nonnative fish initially entering a <br />wetland during inundation include timing and duration of connection, water temperature <br />during the connection period and location of wetland. The biggest factor in determining <br />species composition in the fall is reproduction potential and success. Although the <br />composition of nonnative fish introduced in 2004 was different than the composition that <br />naturally invaded in 2003, this composition was introduced to remain consistent with <br />earlier studies conducted at the Stirrup wetland by Christopherson et. al. 2004. <br />Field Data Collection <br />Sampling of the enclosures at Baeser began 5 August 2003 and was completed on <br />29 August 2003. In 2004, sampling began on 7 July and was completed on 23 July. <br />Enclosures were netted repeatedly to allow abundance and survival estimation by <br />depletion and linear regression. Three fyke nets (two 0.32 cm mesh and one 0.64 cm) <br />were set for four nights in each enclosure. All fish were removed from the fyke nets and <br />placed on a sorting table to quickly recover any surviving razorback sucker or bonytail. <br />All fish captured were removed from the floodplain site. Bonytail and razorback sucker <br />were transferred to The Stirrup wetland, approximately two miles upriver, where <br />conditions were better for long-term survival during the prevailing drought. <br />7 <br />