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During 1998, in the lower Green River, six nets were set per mile. In 1998, control reaches were again identified and sampled. However, the location of the control was changed from those established in 1997. In 1998, RM 120.115 were sampled as the control reach and only ~ electrofishing was conducted in this reach. Electrofishir-g was conducted one day during the sampling period through both the removal and control reaches in a downstream fashion )Eke nets Most nets set in both reaches were baited with approximately three ounces of dry cat food which a was placed in a perforated bag in the cod end of the net. In the lower reach in 1998, nets were used without leads to reduce weight, allowing atwo-person crew to put all 12 nets on the boat, and reduce problems associated with debris and current which caused collapsing and burying of the nets. Nets found with holes, or ones which collapsed during the night were excluded from data analyses. The fyke net bodies were 3 m long and had a 6 m lead attached to the mouth. The ~ mouth was a 1.8 x 1.2 m rectangle which tapered down to a basic hoop net body. The body contained four hoops with a diameter of 0.76 m; within the hoops were two conical throat traps, each with a minimum throat diameter of 15 cm All net walls were made of 2.5 cm braided nylon mesh. Nets were anchored tightly on each end with a fence post or anchor. The net mouth always faced downstream to utilize the scent trail created by the bait and the lead stretched down ~ current and angled to the shore if possible. Nets were set in a variety of habitats, depths and velocities. Velocities ranged from 0 to approx®ately 1 m/s; anything faster collapsed the nets. Nets were generally set 1-2 m deep with maximum depths of approximately 3 m Electrofishing ~ Eleetrofishing was conducted from a 16 foot boat which moved downstream while shocking. The Coffelt VVP settings varied between 100 and 150 volts, 6-8 amps, a pulse width of 60-80%, and a frequency of 40-60 pulses per second. Stunned fish were removed with dip nets and kept in a live well Fish were processed every river mile. Data from the middle Green River control reach were not available for analysis. However, general findings from the Crowl and Badame 2000 report are ~ presented in the results section of this report. Data Collection In 1997 in the lower Green River, all fish collected by fyke nets and during electrofishing were measured for total length (TL), most fish collected greater than 150 mm TL were weighed, and ~ fish less than 150 nun TL had length recorded but were not weighed. In 1997 and 1998 in the middle Green River, and 1998 in the lower Green River, lengths and weights were recorded for the first 25 catfish caught in each section during each fyke netting and electrofishing trip. The total number and total weight were recorded for all remaining nonnatives. ~ A subsample of $annehnouth suckers and bluehead suckers were individually weighed and measured; the remainder were counted and weighed in total Nonnatives captured in the removal reaches were removed from the river. All fish captured in the control reaches were released. Total numbers and weights for catfish were divided into three size classes: small (0.199 mm), medium (200.299 mm), and large (300 mm). Physical data collected included water temperature, flow, aad a subjective measure of turbidity (low, moderate, or high). All rare or endangered native fish captured were identified, weighed, measured, scanned for tags 6 ~