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4 All catfish were sacrificed, and total length in mm (TL) and weight in g were recorded. Total length data allowed ease of comparison with other studies (see Carlander, 1969). One or both pectoral spines were removed at the time of capture for aging. The dried spines were cleaned of all skin and dried flesh and mounted in clear casting resin for sectioning. Mounted spines were sectioned using an apparatus similar to that of Margenau (1982), except that a dremel tool with metal, cutting blades or a jewelers' hand saw was used to cut the sections. Sections were cut at the distal end of the basal recess in an attempt to include all annuli and examined under 25x magnification. Spines were read for the presence of annular rings using methods of Sneed (1951) and Marzolf (1952) Two technicians inspected each section independently to determine the age of each fish, and spine sections were also sent to another investigator for aging. Number of annuli reported by an independent investigator (R. A. Whaley, pers. comm.) agreed with about 90% of the annuli detected by our technicians. Sections were polished by hand using very fine (#600 grit) sandpaper, placed in toluene for clearing, and an image projected (Ken-a-vision model X- 1000-1) at 25 to 40x magnification. Annular radii in each section were measured on a line from the focus to the edge of the longest lobe. The edge of the spine was considered an annulus on fish collected in the non-growing season, (i.e., between October 1 and May 31), and the date of annulus formation was assumed to be 1 January by convention (Jearld, 1983). Total lengths at consecutive annuli were back-calculated using the formula L' _ (S'/S)L where L' = TL at annulus formation, S' = annular radius, S=total spine radius, and L = TL at time of capture. Length-weight relationships were expressed as simple linear regressions, and condition