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Seines were 1/4 inch ace-mesh, 15 ft long by 4 ft deep. In backwaters, seine hauls were made across the long axis of the back- --_ water, from shore to shore whenever possible. When the backwater was too deep to safely cross, the seine haul was begun and ended on the ~ same shoreline, sampling as deep as possible. The first seine haul typically covered the deepest part of the habitat. When rare fishes were collected by either electrofishing or seining, data were recorded and the fish released as soon as possible. All rare fishes were photographed, measured to total length (TL +l mm) and weighed (+20 g). Rare fish longer than 200 mm were given unique numbered, blue ~ Carlin tags. All Gila spp. captured that were 250 mm were photo- graphed on a white background marked with a 1.0 cm grid pattern. Total length, weight, numbers of principal dorsal and anal fin rays, dorsal and anal fin base lengths and nuchal depression were recorded for the Gila spp. fishes that could not be confidently identified in the field were preserved (10~ buffered formal in) for identification in ~ the laboratory. The lower ]6 mi of the study area was sampled by BOR with several gear types. Electrofishing, and a small amount of gill and trammel netting, was conducted in riverine areas. In lacustrine areas gill and trammel nets were used exclusively. Lengths of trammel and gill ~ nets varied from 15.2 to 91.4 m and depths from 0.91 to 1.83 m. Mesh sizes of trammel nets were 38, 51, 57, 64, and 70 mm. Gill net mesh _ sizes were 38, 51, and 64 mm. Nets were set perpendicular to the shoreline. During spring, nets were fished continuously around the clock from March 18, 1987 to April 12, 1987 and during fall from _ September 18 to 27, 1987. Nets were checked twice each day. Back- ~ waters were sampled with seines. Fall systematic sampling was targeted at post-larval, young- of-the-year (YOY) fishes. Backwater habitats were sampled between 20 September and 20 October 1987. Sampling was blocked into 5-mile river reaches. Only backwaters of approximately 30 m2 or greater surface ~ area were seined. Seining procedures were as described earlier for spring and summer. Data recorded for the first seine haul included the following. All rare fishes that could be reliably identified in the field were measured and released. All other fishes reliably identified were ~ counted and released. Unidentified fishes were preserved for identi- fication in the laboratory. In the second seine haul, all rare fishes were handled the same as in the first seine haul. Other fishes reliably identified were released without enumeration. All unidentified fishes and a subsample ~ of YOY Gila spp. were preserved for identification in the laboratory. All adult fishes caught in seine hauls were enumerated and recorded separately. Data collection from, and tagging of, all adult rare species was the same as during spring and summer electrofishing. - 10 -