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<br />LR <br /> <br />backwater surveys by traveling in a boat the entire distance of each 7 mile reach. On a map, each <br />qualifying backwater will be numbered consecutively according to the gear type to be used in sampling. <br />For example, the first backwater encountered that qualifies for seining should be labeled on the map as SE <br /># I and the first fyke net backwater should be labeled FN # I. Numbers will begin at I for each reach. <br />Three backwaters for seining and 3 for fyke netting will be randomly selected from the list for sampling. <br /> <br />The selected backwaters for seining will be sampled with three seine hauls. Hauls will be made across the <br />mouth of the backwater and across points v.. and % of the backwaters total length. Hauls willron <br />perpendicular to the long axis of the backwater (i.e., one shoreline to the other) whenever possible. When <br />the backwater is too deep to safely cross with the seine, a haul parallel to the shoreline may be made. Fyke <br />nets will be positioned in a manner that blocks fish passage into and out of the backwater (i.e. <br />perpendicular to the long axis of the backwater). <br /> <br />Complete physical parameters will be collected for all backwaters sampled. Total length and width of the <br />backwater and the length and width of the area encompassed by each seine haul will be measured. <br />Backwater widths will be measured at the mouth and across points 'h and % of the backwaters total length <br />(these measurements will be the length of the seine hauls unless parallel hauls are made). Water depth (to <br />top of substrate) at the deepest point (DMAX) and at Y, the distance between the deepest point (DMAX) <br />and both shorelines (D I and D2) will be measured (Figure I). If parallel hauls are made, the depth at the <br />deepest point (generally the outside edge of the seine haul) and at v.. and % of the distance between the <br />outside edge of the sampling area will be measured (Figure I). The most common and second most <br />common substrate size at all depth points will be estimated (Table 3). <br /> <br />Table 3. Substrate criteria and codes. <br /> <br />Substrate <br /> <br />Code <br /> <br />Diameter/characteristics <br /> <br /> Very fine material that oozes through frogers when squeezed: no evident granular <br />Silt/Muck Sl composition. <br /> Material tends to stay in hand (does not readily ooze through fingers) when squeezed: <br />Sand SA granular composition -0.1 to 3 nun diameter. <br />Gravel GR Rock material with average diameter of 3 to 76 mm <br />Rubble RU Rock material with average diameter of76 to 305 mm. <br />Boulder BO Rock material with average diameter of 305 nun and larger. <br /> <br />Additional information to be recorded for each backwater includes; river, river mile, date, sampling time, <br />water temperature at location of each seine haul and in the main channel, primary habitat type and <br />secondary habitat type. <br /> <br />All native fish (caught by seining or fyke nets) large enough to reliably identify in the field will be counted <br />by species, measured in total length (% I mm) and released. All other species (seines and fyke nets) will be <br />enumerated if the haul is small enough to do so. Large seine hauls will be preserved in 10% buffered <br />formalin for later laboratory identification of all species. All sample bottles will be labeled inside and <br />outside with sample number, river mile and date. Large fyke net hauls will be enumerated using the <br />technique used for site sampling. <br /> <br />8 <br />