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described below. In the case of a parallel seine, however, depths were taken at the outside edge the net and at points 1/3 and 2/3 the distance from that edge to shore. Habitat Features Sam~linn Physical characteristics of the backwater were measured in conjunction with fish sampling. Forty-six measurements and categorizations were recorded (Figure 2). No measurements were made in the backwater before seining in order to avoid disturbing the fish community. The length (m) of each backwater was measured from the center of the mouth to the extreme upper end using tapes, range finders or known paces. Width (m) of each backwater was taken across the mouth and at points 1/3 and 2/3 the distance from the mouth to the upper end. Depth (m) measurements were taken along each width transect with a 2m staff gauge. The deepest point along each width transect (Dmax) was located and recorded. One depth was then taken on either side of this point and halfway from that point to either shore (D 1 and D2}. Two depth measurements were taken: first, a water depth from the top of the substrate; second, a water plus substrate depth. The latter was measured by pushing down on the staffgauge with moderate pressure and recording total depth to the top of the water column. Subsurface temperatures (°C) were taken at each Dmax. If Dmax exceeded lm, a water temperature was also taken just above the bottom. Other, less rigorous measurements were also taken. Aspect of the backwater mouth was recorded on a 1-5 scale. A value of"1" indicated the mouth opened paza11e1 to downstream flow. If the mouth opened pazallel to flow in an upstream direction it received a "5". Backwaters which opened perpendiculaz to flow received a value of " 3". Turbidity of the backwater at the three 8