Sub-adult channel catfish (Ictalurus punctatus) were marked with fin clips and stocked into 5 Virginia small (13- to 65-ha) impoundments from 1993-1996 to determine optimum stocking size and population dynamics. Four years of treatment stockings were compared to 4 years of standard (fingerling) stockings using gill net and creel surveys. Gill net catch per unit effort (CPUE) was higher (P = 0.04) during the treatment phase, and percentage of marked fish within populations steadily increased and reached a high of 91% in 1997. No evidence of natural reproduction was observed. Overall, abundance and stocking size were directly related (r2 = 0.57, P = 0.01), but there was no significant difference among the 4 treatment cohorts, suggesting that catfish 254-315 mm total length were equally abundant the year following stocking. Harvest was higher (P = 0.05) during and immediately following treatment stockings. Total annual mortality (A) based on cohort analysis ranged from 34%-51%. A catch curve for treatment fish throughout the study yielded an A of 37% (age 2-6). Growth was moderate, as quality size (410 mm) was attained after 2 growing seasons.
