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the data sheet as were northern pike, walleye, largemouth and smallmouth bass and green sunfish. Electrofishing resumed from the point of termination. At the end of each subreach, new data sheets were begun and the elapsed-time clock reset. Sampling continued on one shoreline through an entire Reach after which the crew returned to the top of the Reach and began sampling the opposite shoreline. In most cases the second shoreline was sampled the following day. Beginning in 1993, efforts were made to count all fish encountered in certain subreaches. The intention was to develop an index of fish abundance in order to detect fluctuations in all fish species. Initially (1993) counts were made in an alternating fashion from one shore to the next over 30 minute time intervals. This resulted in a checkerboard arrangement of surveyed sections. This method was modified in 1994 to make the method standard and repeatable. Alt fish encountered in the first mile of each shoreline in each subreach were counted. This removed the variability due- to travel time, allowed for direct computation of fish per mile and standardized the areas sampled. ^'~ F- ~-3 R~ k-' [. ^~e •.:, d rd -.~ ;~ ISMP Young-of-the-year Monitoring Sampling for YOY squawfish was conducted in the fall between 20 September and •10 October, before main channel and backwater temperatures equalized and while YOY squawfish were still likely to be present in backwater areas. The 104 mile monitoring Reach was divided into 5-mile .subreaches for sampling purposes. Sampling began at the upstream end of the Reach and proceeded downstream. A 3-5 person crew stopped at the first 2 suitable backwaters (> 30 my x I ft deep) encountered in each S- mile subreach. The first backwater encountered was called the Primary backwater, while the second was classified the Secondary backwater. Two non-overlapping seine hauls were made in each backwater using a 4 m wide by 1.2 m deep, 3.2 nun ace-mesh beach seine. All seine hauls were pulled across the backwater from shore to shore, except where water depth made this impossible. If depths were too great, the haul was made parallel to the shore of the backwater, extending as far into the backwater as possible. Both the interface with the main channel and the shallow upper end of the backwater were avoided in the sampling procedure. Whenever possible, the first seine haul sampled the deepest part of the backwater. All fish caught in the first seine haul in the Primary backwater were enumerated. Colorado squawfish were measured to Length and released. All other fishes that could be effectively and quickly counted, were counted and released. Remaining fish were preserved in 10% buffered formaldehyde for later laboratory identification. Buckets and small aquarium type dip-nets facilitated the counting and measuring of YOY squawfish. The second seine haul in the Primary backwater and both seine hauls in the Secondary 6